    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one or more
    003 * contributor license agreements.  See the NOTICE file distributed with
    004 * this work for additional information regarding copyright ownership.
    005 * The ASF licenses this file to You under the Apache License, Version 2.0
    006 * (the "License"); you may not use this file except in compliance with
    007 * the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 * Unless required by applicable law or agreed to in writing, software
    012 * distributed under the License is distributed on an "AS IS" BASIS,
    013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 * See the License for the specific language governing permissions and
    015 * limitations under the License.
    016 */
    017package org.apache.commons.lang3;
    018
    019import java.lang.reflect.Method;
    020import java.lang.reflect.Modifier;
    021import java.util.ArrayList;
    022import java.util.Collections;
    023import java.util.HashMap;
    024import java.util.HashSet;
    025import java.util.Iterator;
    026import java.util.LinkedHashSet;
    027import java.util.List;
    028import java.util.Map;
    029import java.util.Set;
    030
    031import org.apache.commons.lang3.mutable.MutableObject;
    032
    033/**
    034 * <p>Operates on classes without using reflection.</p>
    035 *
    036 * <p>This class handles invalid {@code null} inputs as best it can.
    037 * Each method documents its behavior in more detail.</p>
    038 *
    039 * <p>The notion of a {@code canonical name} includes the human
    040 * readable name for the type, for example {@code int[]}. The
    041 * non-canonical method variants work with the JVM names, such as
    042 * {@code [I}. </p>
    043 *
    044 * @since 2.0
    045 */
    046public class ClassUtils {
    047
    048    /**
    049     * Inclusivity literals for {@link #hierarchy(Class, Interfaces)}.
    050     * @since 3.2
    051     */
    052    public enum Interfaces {
    053
    054        /** Includes interfaces. */
    055        INCLUDE,
    056
    057        /** Excludes interfaces. */
    058        EXCLUDE
    059    }
    060
    061    /**
    062     * The package separator character: {@code '&#x2e;' == {@value}}.
    063     */
    064    public static final char PACKAGE_SEPARATOR_CHAR = '.';
    065
    066    /**
    067     * The package separator String: {@code "&#x2e;"}.
    068     */
    069    public static final String PACKAGE_SEPARATOR = String.valueOf(PACKAGE_SEPARATOR_CHAR);
    070
    071    /**
    072     * The inner class separator character: {@code '$' == {@value}}.
    073     */
    074    public static final char INNER_CLASS_SEPARATOR_CHAR = '$';
    075
    076    /**
    077     * The inner class separator String: {@code "$"}.
    078     */
    079    public static final String INNER_CLASS_SEPARATOR = String.valueOf(INNER_CLASS_SEPARATOR_CHAR);
    080
    081    /**
    082     * Maps names of primitives to their corresponding primitive {@code Class}es.
    083     */
    084    private static final Map<String, Class<?>> namePrimitiveMap = new HashMap<>();
    085    static {
    086         namePrimitiveMap.put("boolean", Boolean.TYPE);
    087         namePrimitiveMap.put("byte", Byte.TYPE);
    088         namePrimitiveMap.put("char", Character.TYPE);
    089         namePrimitiveMap.put("short", Short.TYPE);
    090         namePrimitiveMap.put("int", Integer.TYPE);
    091         namePrimitiveMap.put("long", Long.TYPE);
    092         namePrimitiveMap.put("double", Double.TYPE);
    093         namePrimitiveMap.put("float", Float.TYPE);
    094         namePrimitiveMap.put("void", Void.TYPE);
    095    }
    096
    097    /**
    098     * Maps primitive {@code Class}es to their corresponding wrapper {@code Class}.
    099     */
    100    private static final Map<Class<?>, Class<?>> primitiveWrapperMap = new HashMap<>();
    101    static {
    102         primitiveWrapperMap.put(Boolean.TYPE, Boolean.class);
    103         primitiveWrapperMap.put(Byte.TYPE, Byte.class);
    104         primitiveWrapperMap.put(Character.TYPE, Character.class);
    105         primitiveWrapperMap.put(Short.TYPE, Short.class);
    106         primitiveWrapperMap.put(Integer.TYPE, Integer.class);
    107         primitiveWrapperMap.put(Long.TYPE, Long.class);
    108         primitiveWrapperMap.put(Double.TYPE, Double.class);
    109         primitiveWrapperMap.put(Float.TYPE, Float.class);
    110         primitiveWrapperMap.put(Void.TYPE, Void.TYPE);
    111    }
    112
    113    /**
    114     * Maps wrapper {@code Class}es to their corresponding primitive types.
    115     */
    116    private static final Map<Class<?>, Class<?>> wrapperPrimitiveMap = new HashMap<>();
    117    static {
    118        for (final Map.Entry<Class<?>, Class<?>> entry : primitiveWrapperMap.entrySet()) {
    119            final Class<?> primitiveClass = entry.getKey();
    120            final Class<?> wrapperClass = entry.getValue();
    121            if (!primitiveClass.equals(wrapperClass)) {
    122                wrapperPrimitiveMap.put(wrapperClass, primitiveClass);
    123            }
    124        }
    125    }
    126
    127    /**
    128     * Maps a primitive class name to its corresponding abbreviation used in array class names.
    129     */
    130    private static final Map<String, String> abbreviationMap;
    131
    132    /**
    133     * Maps an abbreviation used in array class names to corresponding primitive class name.
    134     */
    135    private static final Map<String, String> reverseAbbreviationMap;
    136    // Feed abbreviation maps
    137    static {
    138        final Map<String, String> m = new HashMap<>();
    139        m.put("int", "I");
    140        m.put("boolean", "Z");
    141        m.put("float", "F");
    142        m.put("long", "J");
    143        m.put("short", "S");
    144        m.put("byte", "B");
    145        m.put("double", "D");
    146        m.put("char", "C");
    147        final Map<String, String> r = new HashMap<>();
    148        for (final Map.Entry<String, String> e : m.entrySet()) {
    149            r.put(e.getValue(), e.getKey());
    150        }
    151        abbreviationMap = Collections.unmodifiableMap(m);
    152        reverseAbbreviationMap = Collections.unmodifiableMap(r);
    153    }
    154
    155    /**
    156     * <p>ClassUtils instances should NOT be constructed in standard programming.
    157     * Instead, the class should be used as
    158     * {@code ClassUtils.getShortClassName(cls)}.</p>
    159     *
    160     * <p>This constructor is public to permit tools that require a JavaBean
    161     * instance to operate.</p>
    162     */
    163    public ClassUtils() {
    164      super();
    165    }
    166
    167    // Short class name
    168    // ----------------------------------------------------------------------
    169    /**
    170     * <p>Gets the class name of the {@code object} without the package name or names.</p>
    171     *
    172     * <p>The method looks up the class of the object and then converts the name of the class invoking
    173     * {@link #getShortClassName(Class)} (see relevant notes there).</p>
    174     *
    175     * @param object  the class to get the short name for, may be {@code null}
    176     * @param valueIfNull  the value to return if the object is {@code null}
    177     * @return the class name of the object without the package name, or {@code valueIfNull}
    178     *         if the argument {@code object} is {@code null}
    179     */
    180    public static String getShortClassName(final Object object, final String valueIfNull) {
    181        if (object == null) {
    182            return valueIfNull;
    183        }
    184        return getShortClassName(object.getClass());
    185    }
    186
    187    /**
    188     * <p>Gets the class name minus the package name from a {@code Class}.</p>
    189     *
    190     * <p>This method simply gets the name using {@code Class.getName()} and then calls
    191     * {@link #getShortClassName(Class)}. See relevant notes there.</p>
    192     *
    193     * @param cls  the class to get the short name for.
    194     * @return the class name without the package name or an empty string. If the class
    195     *         is an inner class then the returned value will contain the outer class
    196     *         or classes separated with {@code .} (dot) character.
    197     */
    198    public static String getShortClassName(final Class<?> cls) {
    199        if (cls == null) {
    200            return StringUtils.EMPTY;
    201        }
    202        return getShortClassName(cls.getName());
    203    }
    204
    205    /**
    206     * <p>Gets the class name minus the package name from a String.</p>
    207     *
    208     * <p>The string passed in is assumed to be a class name - it is not checked. The string has to be formatted the way
    209     * as the JDK method {@code Class.getName()} returns it, and not the usual way as we write it, for example in import
    210     * statements, or as it is formatted by {@code Class.getCanonicalName()}.</p>
    211     *
    212     * <p>The difference is is significant only in case of classes that are inner classes of some other
    213     * classes. In this case the separator between the outer and inner class (possibly on multiple hierarchy level) has
    214     * to be {@code $} (dollar sign) and not {@code .} (dot), as it is returned by {@code Class.getName()}</p>
    215     *
    216     * <p>Note that this method is called from the {@link #getShortClassName(Class)} method using the string
    217     * returned by {@code Class.getName()}.</p>
    218     *
    219     * <p>Note that this method differs from {@link #getSimpleName(Class)} in that this will
    220     * return, for example {@code "Map.Entry"} whilst the {@code java.lang.Class} variant will simply
    221     * return {@code "Entry"}. In this example the argument {@code className} is the string
    222     * {@code java.util.Map$Entry} (note the {@code $} sign.</p>
    223     *
    224     * @param className  the className to get the short name for. It has to be formatted as returned by
    225     *                   {@code Class.getName()} and not {@code Class.getCanonicalName()}
    226     * @return the class name of the class without the package name or an empty string. If the class is
    227     *         an inner class then value contains the outer class or classes and the separator is replaced
    228     *         to be {@code .} (dot) character.
    229     */
    230    public static String getShortClassName(String className) {
    231        if (StringUtils.isEmpty(className)) {
    232            return StringUtils.EMPTY;
    233        }
    234
    235        final StringBuilder arrayPrefix = new StringBuilder();
    236
    237        // Handle array encoding
    238        if (className.startsWith("[")) {
    239            while (className.charAt(0) == '[') {
    240                className = className.substring(1);
    241                arrayPrefix.append("[]");
    242            }
    243            // Strip Object type encoding
    244            if (className.charAt(0) == 'L' && className.charAt(className.length() - 1) == ';') {
    245                className = className.substring(1, className.length() - 1);
    246            }
    247
    248            if (reverseAbbreviationMap.containsKey(className)) {
    249                className = reverseAbbreviationMap.get(className);
    250            }
    251        }
    252
    253        final int lastDotIdx = className.lastIndexOf(PACKAGE_SEPARATOR_CHAR);
    254        final int innerIdx = className.indexOf(
    255                INNER_CLASS_SEPARATOR_CHAR, lastDotIdx == -1 ? 0 : lastDotIdx + 1);
    256        String out = className.substring(lastDotIdx + 1);
    257        if (innerIdx != -1) {
    258            out = out.replace(INNER_CLASS_SEPARATOR_CHAR, PACKAGE_SEPARATOR_CHAR);
    259        }
    260        return out + arrayPrefix;
    261    }
    262
    263    /**
    264     * <p>Null-safe version of {@code cls.getSimpleName()}</p>
    265     *
    266     * @param cls the class for which to get the simple name; may be null
    267     * @return the simple class name or the empty string in case the argument is {@code null}
    268     * @since 3.0
    269     * @see Class#getSimpleName()
    270     */
    271    public static String getSimpleName(final Class<?> cls) {
    272        return getSimpleName(cls, StringUtils.EMPTY);
    273    }
    274
    275    /**
    276     * <p>Null-safe version of {@code cls.getSimpleName()}</p>
    277     *
    278     * @param cls the class for which to get the simple name; may be null
    279     * @param valueIfNull  the value to return if null
    280     * @return the simple class name or {@code valueIfNull} if the
    281     *         argument {@code cls} is {@code null}
    282     * @since 3.0
    283     * @see Class#getSimpleName()
    284     */
    285    public static String getSimpleName(final Class<?> cls, final String valueIfNull) {
    286        return cls == null ? valueIfNull : cls.getSimpleName();
    287    }
    288
    289    /**
    290     * <p>Null-safe version of {@code object.getClass().getSimpleName()}</p>
    291     *
    292     * <p>It is to note that this method is overloaded and in case the argument {@code object} is a
    293     * {@code Class} object then the {@link #getSimpleName(Class)} will be invoked. If this is
    294     * a significant possibility then the caller should check this case and call {@code
    295     * getSimpleName(Class.class)} or just simply use the string literal {@code "Class"}, which
    296     * is the result of the method in that case.</p>
    297     *
    298     * @param object the object for which to get the simple class name; may be null
    299     * @return the simple class name or the empty string in case the argument is {@code null}
    300     * @since 3.7
    301     * @see Class#getSimpleName()
    302     */
    303    public static String getSimpleName(final Object object) {
    304        return getSimpleName(object, StringUtils.EMPTY);
    305    }
    306
    307    /**
    308     * <p>Null-safe version of {@code object.getClass().getSimpleName()}</p>
    309     *
    310     * @param object the object for which to get the simple class name; may be null
    311     * @param valueIfNull the value to return if {@code object} is {@code null}
    312     * @return the simple class name or {@code valueIfNull} if the
    313     *         argument {@code object} is {@code null}
    314     * @since 3.0
    315     * @see Class#getSimpleName()
    316     */
    317    public static String getSimpleName(final Object object, final String valueIfNull) {
    318        return object == null ? valueIfNull : object.getClass().getSimpleName();
    319    }
    320
    321    /**
    322     * <p>Null-safe version of {@code cls.getName()}</p>
    323     *
    324     * @param cls the class for which to get the class name; may be null
    325     * @return the class name or the empty string in case the argument is {@code null}
    326     * @since 3.7
    327     * @see Class#getSimpleName()
    328     */
    329    public static String getName(final Class<?> cls) {
    330        return getName(cls, StringUtils.EMPTY);
    331    }
    332
    333    /**
    334     * <p>Null-safe version of {@code cls.getName()}</p>
    335     *
    336     * @param cls the class for which to get the class name; may be null
    337     * @param valueIfNull the return value if the argument {@code cls} is {@code null}
    338     * @return the class name or {@code valueIfNull}
    339     * @since 3.7
    340     * @see Class#getName()
    341     */
    342    public static String getName(final Class<?> cls, final String valueIfNull) {
    343        return cls == null ? valueIfNull : cls.getName();
    344    }
    345
    346    /**
    347     * <p>Null-safe version of {@code object.getClass().getName()}</p>
    348     *
    349     * @param object the object for which to get the class name; may be null
    350     * @return the class name or the empty String
    351     * @since 3.7
    352     * @see Class#getSimpleName()
    353     */
    354    public static String getName(final Object object) {
    355        return getName(object, StringUtils.EMPTY);
    356    }
    357
    358    /**
    359     * <p>Null-safe version of {@code object.getClass().getSimpleName()}</p>
    360     *
    361     * @param object the object for which to get the class name; may be null
    362     * @param valueIfNull the value to return if {@code object} is {@code null}
    363     * @return the class name or {@code valueIfNull}
    364     * @since 3.0
    365     * @see Class#getName()
    366     */
    367    public static String getName(final Object object, final String valueIfNull) {
    368        return object == null ? valueIfNull : object.getClass().getName();
    369    }
    370
    371    // Package name
    372    // ----------------------------------------------------------------------
    373    /**
    374     * <p>Gets the package name of an {@code Object}.</p>
    375     *
    376     * @param object  the class to get the package name for, may be null
    377     * @param valueIfNull  the value to return if null
    378     * @return the package name of the object, or the null value
    379     */
    380    public static String getPackageName(final Object object, final String valueIfNull) {
    381        if (object == null) {
    382            return valueIfNull;
    383        }
    384        return getPackageName(object.getClass());
    385    }
    386
    387    /**
    388     * <p>Gets the package name of a {@code Class}.</p>
    389     *
    390     * @param cls  the class to get the package name for, may be {@code null}.
    391     * @return the package name or an empty string
    392     */
    393    public static String getPackageName(final Class<?> cls) {
    394        if (cls == null) {
    395            return StringUtils.EMPTY;
    396        }
    397        return getPackageName(cls.getName());
    398    }
    399
    400    /**
    401     * <p>Gets the package name from a {@code String}.</p>
    402     *
    403     * <p>The string passed in is assumed to be a class name - it is not checked.</p>
    404     * <p>If the class is unpackaged, return an empty string.</p>
    405     *
    406     * @param className  the className to get the package name for, may be {@code null}
    407     * @return the package name or an empty string
    408     */
    409    public static String getPackageName(String className) {
    410        if (StringUtils.isEmpty(className)) {
    411            return StringUtils.EMPTY;
    412        }
    413
    414        // Strip array encoding
    415        while (className.charAt(0) == '[') {
    416            className = className.substring(1);
    417        }
    418        // Strip Object type encoding
    419        if (className.charAt(0) == 'L' && className.charAt(className.length() - 1) == ';') {
    420            className = className.substring(1);
    421        }
    422
    423        final int i = className.lastIndexOf(PACKAGE_SEPARATOR_CHAR);
    424        if (i == -1) {
    425            return StringUtils.EMPTY;
    426        }
    427        return className.substring(0, i);
    428    }
    429
    430    // Abbreviated name
    431    // ----------------------------------------------------------------------
    432    /**
    433     * <p>Gets the abbreviated name of a {@code Class}.</p>
    434     *
    435     * @param cls  the class to get the abbreviated name for, may be {@code null}
    436     * @param lengthHint  the desired length of the abbreviated name
    437     * @return the abbreviated name or an empty string
    438     * @throws IllegalArgumentException if len &lt;= 0
    439     * @see #getAbbreviatedName(String, int)
    440     * @since 3.4
    441     */
    442    public static String getAbbreviatedName(final Class<?> cls, final int lengthHint) {
    443      if (cls == null) {
    444        return StringUtils.EMPTY;
    445      }
    446      return getAbbreviatedName(cls.getName(), lengthHint);
    447    }
    448
    449    /**
    450     * <p>Gets the abbreviated class name from a {@code String}.</p>
    451     *
    452     * <p>The string passed in is assumed to be a class name - it is not checked.</p>
    453     *
    454     * <p>The abbreviation algorithm will shorten the class name, usually without
    455     * significant loss of meaning.</p>
    456     *
    457     * <p>The abbreviated class name will always include the complete package hierarchy.
    458     * If enough space is available, rightmost sub-packages will be displayed in full
    459     * length. The abbreviated package names will be shortened to a single character.</p>
    460     * <p>Only package names are shortened, the class simple name remains untouched. (See examples.)</p>
    461     * <p>The result will be longer than the desired length only if all the package names
    462     * shortened to a single character plus the class simple name with the separating dots
    463     * together are longer than the desired length. In other words, when the class name
    464     * cannot be shortened to the desired length.</p>
    465     * <p>If the class name can be shortened then
    466     * the final length will be at most {@code lengthHint} characters.</p>
    467     * <p>If the {@code lengthHint} is zero or negative then the method
    468     * throws exception. If you want to achieve the shortest possible version then
    469     * use {@code 1} as a {@code lengthHint}.</p>
    470     *
    471     * <table>
    472     * <caption>Examples</caption>
    473     * <tr><td>className</td><td>len</td><td>return</td></tr>
    474     * <tr><td>              null</td><td> 1</td><td>""</td></tr>
    475     * <tr><td>"java.lang.String"</td><td> 5</td><td>"j.l.String"</td></tr>
    476     * <tr><td>"java.lang.String"</td><td>15</td><td>"j.lang.String"</td></tr>
    477     * <tr><td>"java.lang.String"</td><td>30</td><td>"java.lang.String"</td></tr>
    478     * <tr><td>"org.apache.commons.lang3.ClassUtils"</td><td>18</td><td>"o.a.c.l.ClassUtils"</td></tr>
    479     * </table>
    480     *
    481     * @param className the className to get the abbreviated name for, may be {@code null}
    482     * @param lengthHint       the desired length of the abbreviated name
    483     * @return the abbreviated name or an empty string if the specified
    484     * class name is {@code null} or empty string. The abbreviated name may be
    485     * longer than the desired length if it cannot be abbreviated to the desired length.
    486     * @throws IllegalArgumentException if {@code len <= 0}
    487     * @since 3.4
    488     */
    489    public static String getAbbreviatedName(final String className, final int lengthHint) {
    490        if (lengthHint <= 0) {
    491            throw new IllegalArgumentException("len must be > 0");
    492        }
    493        if (className == null) {
    494            return StringUtils.EMPTY;
    495        }
    496        if (className.length() <= lengthHint) {
    497            return className;
    498        }
    499        final char[] abbreviated = className.toCharArray();
    500        int target = 0;
    501        int source = 0;
    502        while (source < abbreviated.length) {
    503            // copy the next part
    504            int runAheadTarget = target;
    505            while (source < abbreviated.length && abbreviated[source] != '.') {
    506                abbreviated[runAheadTarget++] = abbreviated[source++];
    507            }
    508
    509            ++target;
    510            if (useFull(runAheadTarget, source, abbreviated.length, lengthHint)
    511                  || target > runAheadTarget) {
    512                target = runAheadTarget;
    513            }
    514
    515            // copy the '.' unless it was the last part
    516            if (source < abbreviated.length) {
    517                abbreviated[target++] = abbreviated[source++];
    518            }
    519        }
    520        return new String(abbreviated, 0, target);
    521    }
    522
    523    /**
    524     * <p>Decides if the part that was just copied to its destination
    525     * location in the work array can be kept as it was copied or must be
    526     * abbreviated. It must be kept when the part is the last one, which
    527     * is the simple name of the class. In this case the {@code source}
    528     * index, from where the characters are copied points one position
    529     * after the last character, a.k.a. {@code source ==
    530     * originalLength}</p>
    531     *
    532     * <p>If the part is not the last one then it can be kept
    533     * unabridged if the number of the characters copied so far plus
    534     * the character that are to be copied is less than or equal to the
    535     * desired length.</p>
    536     *
    537     * @param runAheadTarget the target index (where the characters were
    538     *                       copied to) pointing after the last character
    539     *                       copied when the current part was copied
    540     * @param source         the source index (where the characters were
    541     *                       copied from) pointing after the last
    542     *                       character copied when the current part was
    543     *                       copied
    544     * @param originalLength the original length of the class full name,
    545     *                       which is abbreviated
    546     * @param desiredLength  the desired length of the abbreviated class
    547     *                       name
    548     * @return {@code true} if it can be kept in its original length
    549     * {@code false} if the current part has to be abbreviated and
    550     */
    551    private static boolean useFull(final int runAheadTarget,
    552                                   final int source,
    553                                   final int originalLength,
    554                                   final int desiredLength) {
    555        return source >= originalLength ||
    556            runAheadTarget + originalLength - source <= desiredLength;
    557    }
    558
    559    // Superclasses/Superinterfaces
    560    // ----------------------------------------------------------------------
    561    /**
    562     * <p>Gets a {@code List} of superclasses for the given class.</p>
    563     *
    564     * @param cls  the class to look up, may be {@code null}
    565     * @return the {@code List} of superclasses in order going up from this one
    566     *  {@code null} if null input
    567     */
    568    public static List<Class<?>> getAllSuperclasses(final Class<?> cls) {
    569        if (cls == null) {
    570            return null;
    571        }
    572        final List<Class<?>> classes = new ArrayList<>();
    573        Class<?> superclass = cls.getSuperclass();
    574        while (superclass != null) {
    575            classes.add(superclass);
    576            superclass = superclass.getSuperclass();
    577        }
    578        return classes;
    579    }
    580
    581    /**
    582     * <p>Gets a {@code List} of all interfaces implemented by the given
    583     * class and its superclasses.</p>
    584     *
    585     * <p>The order is determined by looking through each interface in turn as
    586     * declared in the source file and following its hierarchy up. Then each
    587     * superclass is considered in the same way. Later duplicates are ignored,
    588     * so the order is maintained.</p>
    589     *
    590     * @param cls  the class to look up, may be {@code null}
    591     * @return the {@code List} of interfaces in order,
    592     *  {@code null} if null input
    593     */
    594    public static List<Class<?>> getAllInterfaces(final Class<?> cls) {
    595        if (cls == null) {
    596            return null;
    597        }
    598
    599        final LinkedHashSet<Class<?>> interfacesFound = new LinkedHashSet<>();
    600        getAllInterfaces(cls, interfacesFound);
    601
    602        return new ArrayList<>(interfacesFound);
    603    }
    604
    605    /**
    606     * Gets the interfaces for the specified class.
    607     *
    608     * @param cls  the class to look up, may be {@code null}
    609     * @param interfacesFound the {@code Set} of interfaces for the class
    610     */
    611    private static void getAllInterfaces(Class<?> cls, final HashSet<Class<?>> interfacesFound) {
    612        while (cls != null) {
    613            final Class<?>[] interfaces = cls.getInterfaces();
    614
    615            for (final Class<?> i : interfaces) {
    616                if (interfacesFound.add(i)) {
    617                    getAllInterfaces(i, interfacesFound);
    618                }
    619            }
    620
    621            cls = cls.getSuperclass();
    622         }
    623     }
    624
    625    // Convert list
    626    // ----------------------------------------------------------------------
    627    /**
    628     * <p>Given a {@code List} of class names, this method converts them into classes.</p>
    629     *
    630     * <p>A new {@code List} is returned. If the class name cannot be found, {@code null}
    631     * is stored in the {@code List}. If the class name in the {@code List} is
    632     * {@code null}, {@code null} is stored in the output {@code List}.</p>
    633     *
    634     * @param classNames  the classNames to change
    635     * @return a {@code List} of Class objects corresponding to the class names,
    636     *  {@code null} if null input
    637     * @throws ClassCastException if classNames contains a non String entry
    638     */
    639    public static List<Class<?>> convertClassNamesToClasses(final List<String> classNames) {
    640        if (classNames == null) {
    641            return null;
    642        }
    643        final List<Class<?>> classes = new ArrayList<>(classNames.size());
    644        for (final String className : classNames) {
    645            try {
    646                classes.add(Class.forName(className));
    647            } catch (final Exception ex) {
    648                classes.add(null);
    649            }
    650        }
    651        return classes;
    652    }
    653
    654    /**
    655     * <p>Given a {@code List} of {@code Class} objects, this method converts
    656     * them into class names.</p>
    657     *
    658     * <p>A new {@code List} is returned. {@code null} objects will be copied into
    659     * the returned list as {@code null}.</p>
    660     *
    661     * @param classes  the classes to change
    662     * @return a {@code List} of class names corresponding to the Class objects,
    663     *  {@code null} if null input
    664     * @throws ClassCastException if {@code classes} contains a non-{@code Class} entry
    665     */
    666    public static List<String> convertClassesToClassNames(final List<Class<?>> classes) {
    667        if (classes == null) {
    668            return null;
    669        }
    670        final List<String> classNames = new ArrayList<>(classes.size());
    671        for (final Class<?> cls : classes) {
    672            if (cls == null) {
    673                classNames.add(null);
    674            } else {
    675                classNames.add(cls.getName());
    676            }
    677        }
    678        return classNames;
    679    }
    680
    681    // Is assignable
    682    // ----------------------------------------------------------------------
    683    /**
    684     * <p>Checks if an array of Classes can be assigned to another array of Classes.</p>
    685     *
    686     * <p>This method calls {@link #isAssignable(Class, Class) isAssignable} for each
    687     * Class pair in the input arrays. It can be used to check if a set of arguments
    688     * (the first parameter) are suitably compatible with a set of method parameter types
    689     * (the second parameter).</p>
    690     *
    691     * <p>Unlike the {@link Class#isAssignableFrom(java.lang.Class)} method, this
    692     * method takes into account widenings of primitive classes and
    693     * {@code null}s.</p>
    694     *
    695     * <p>Primitive widenings allow an int to be assigned to a {@code long},
    696     * {@code float} or {@code double}. This method returns the correct
    697     * result for these cases.</p>
    698     *
    699     * <p>{@code Null} may be assigned to any reference type. This method will
    700     * return {@code true} if {@code null} is passed in and the toClass is
    701     * non-primitive.</p>
    702     *
    703     * <p>Specifically, this method tests whether the type represented by the
    704     * specified {@code Class} parameter can be converted to the type
    705     * represented by this {@code Class} object via an identity conversion
    706     * widening primitive or widening reference conversion. See
    707     * <em><a href="http://docs.oracle.com/javase/specs/">The Java Language Specification</a></em>,
    708     * sections 5.1.1, 5.1.2 and 5.1.4 for details.</p>
    709     *
    710     * <p><strong>Since Lang 3.0,</strong> this method will default behavior for
    711     * calculating assignability between primitive and wrapper types <em>corresponding
    712     * to the running Java version</em>; i.e. autoboxing will be the default
    713     * behavior in VMs running Java versions &gt; 1.5.</p>
    714     *
    715     * @param classArray  the array of Classes to check, may be {@code null}
    716     * @param toClassArray  the array of Classes to try to assign into, may be {@code null}
    717     * @return {@code true} if assignment possible
    718     */
    719    public static boolean isAssignable(final Class<?>[] classArray, final Class<?>... toClassArray) {
    720        return isAssignable(classArray, toClassArray, true);
    721    }
    722
    723    /**
    724     * <p>Checks if an array of Classes can be assigned to another array of Classes.</p>
    725     *
    726     * <p>This method calls {@link #isAssignable(Class, Class) isAssignable} for each
    727     * Class pair in the input arrays. It can be used to check if a set of arguments
    728     * (the first parameter) are suitably compatible with a set of method parameter types
    729     * (the second parameter).</p>
    730     *
    731     * <p>Unlike the {@link Class#isAssignableFrom(java.lang.Class)} method, this
    732     * method takes into account widenings of primitive classes and
    733     * {@code null}s.</p>
    734     *
    735     * <p>Primitive widenings allow an int to be assigned to a {@code long},
    736     * {@code float} or {@code double}. This method returns the correct
    737     * result for these cases.</p>
    738     *
    739     * <p>{@code Null} may be assigned to any reference type. This method will
    740     * return {@code true} if {@code null} is passed in and the toClass is
    741     * non-primitive.</p>
    742     *
    743     * <p>Specifically, this method tests whether the type represented by the
    744     * specified {@code Class} parameter can be converted to the type
    745     * represented by this {@code Class} object via an identity conversion
    746     * widening primitive or widening reference conversion. See
    747     * <em><a href="http://docs.oracle.com/javase/specs/">The Java Language Specification</a></em>,
    748     * sections 5.1.1, 5.1.2 and 5.1.4 for details.</p>
    749     *
    750     * @param classArray  the array of Classes to check, may be {@code null}
    751     * @param toClassArray  the array of Classes to try to assign into, may be {@code null}
    752     * @param autoboxing  whether to use implicit autoboxing/unboxing between primitives and wrappers
    753     * @return {@code true} if assignment possible
    754     */
    755    public static boolean isAssignable(Class<?>[] classArray, Class<?>[] toClassArray, final boolean autoboxing) {
    756        if (!ArrayUtils.isSameLength(classArray, toClassArray)) {
    757            return false;
    758        }
    759        if (classArray == null) {
    760            classArray = ArrayUtils.EMPTY_CLASS_ARRAY;
    761        }
    762        if (toClassArray == null) {
    763            toClassArray = ArrayUtils.EMPTY_CLASS_ARRAY;
    764        }
    765        for (int i = 0; i < classArray.length; i++) {
    766            if (!isAssignable(classArray[i], toClassArray[i], autoboxing)) {
    767                return false;
    768            }
    769        }
    770        return true;
    771    }
    772
    773    /**
    774     * Returns whether the given {@code type} is a primitive or primitive wrapper ({@link Boolean}, {@link Byte}, {@link Character},
    775     * {@link Short}, {@link Integer}, {@link Long}, {@link Double}, {@link Float}).
    776     *
    777     * @param type
    778     *            The class to query or null.
    779     * @return true if the given {@code type} is a primitive or primitive wrapper ({@link Boolean}, {@link Byte}, {@link Character},
    780     *         {@link Short}, {@link Integer}, {@link Long}, {@link Double}, {@link Float}).
    781     * @since 3.1
    782     */
    783    public static boolean isPrimitiveOrWrapper(final Class<?> type) {
    784        if (type == null) {
    785            return false;
    786        }
    787        return type.isPrimitive() || isPrimitiveWrapper(type);
    788    }
    789
    790    /**
    791     * Returns whether the given {@code type} is a primitive wrapper ({@link Boolean}, {@link Byte}, {@link Character}, {@link Short},
    792     * {@link Integer}, {@link Long}, {@link Double}, {@link Float}).
    793     *
    794     * @param type
    795     *            The class to query or null.
    796     * @return true if the given {@code type} is a primitive wrapper ({@link Boolean}, {@link Byte}, {@link Character}, {@link Short},
    797     *         {@link Integer}, {@link Long}, {@link Double}, {@link Float}).
    798     * @since 3.1
    799     */
    800    public static boolean isPrimitiveWrapper(final Class<?> type) {
    801        return wrapperPrimitiveMap.containsKey(type);
    802    }
    803
    804    /**
    805     * <p>Checks if one {@code Class} can be assigned to a variable of
    806     * another {@code Class}.</p>
    807     *
    808     * <p>Unlike the {@link Class#isAssignableFrom(java.lang.Class)} method,
    809     * this method takes into account widenings of primitive classes and
    810     * {@code null}s.</p>
    811     *
    812     * <p>Primitive widenings allow an int to be assigned to a long, float or
    813     * double. This method returns the correct result for these cases.</p>
    814     *
    815     * <p>{@code Null} may be assigned to any reference type. This method
    816     * will return {@code true} if {@code null} is passed in and the
    817     * toClass is non-primitive.</p>
    818     *
    819     * <p>Specifically, this method tests whether the type represented by the
    820     * specified {@code Class} parameter can be converted to the type
    821     * represented by this {@code Class} object via an identity conversion
    822     * widening primitive or widening reference conversion. See
    823     * <em><a href="http://docs.oracle.com/javase/specs/">The Java Language Specification</a></em>,
    824     * sections 5.1.1, 5.1.2 and 5.1.4 for details.</p>
    825     *
    826     * <p><strong>Since Lang 3.0,</strong> this method will default behavior for
    827     * calculating assignability between primitive and wrapper types <em>corresponding
    828     * to the running Java version</em>; i.e. autoboxing will be the default
    829     * behavior in VMs running Java versions &gt; 1.5.</p>
    830     *
    831     * @param cls  the Class to check, may be null
    832     * @param toClass  the Class to try to assign into, returns false if null
    833     * @return {@code true} if assignment possible
    834     */
    835    public static boolean isAssignable(final Class<?> cls, final Class<?> toClass) {
    836        return isAssignable(cls, toClass, true);
    837    }
    838
    839    /**
    840     * <p>Checks if one {@code Class} can be assigned to a variable of
    841     * another {@code Class}.</p>
    842     *
    843     * <p>Unlike the {@link Class#isAssignableFrom(java.lang.Class)} method,
    844     * this method takes into account widenings of primitive classes and
    845     * {@code null}s.</p>
    846     *
    847     * <p>Primitive widenings allow an int to be assigned to a long, float or
    848     * double. This method returns the correct result for these cases.</p>
    849     *
    850     * <p>{@code Null} may be assigned to any reference type. This method
    851     * will return {@code true} if {@code null} is passed in and the
    852     * toClass is non-primitive.</p>
    853     *
    854     * <p>Specifically, this method tests whether the type represented by the
    855     * specified {@code Class} parameter can be converted to the type
    856     * represented by this {@code Class} object via an identity conversion
    857     * widening primitive or widening reference conversion. See
    858     * <em><a href="http://docs.oracle.com/javase/specs/">The Java Language Specification</a></em>,
    859     * sections 5.1.1, 5.1.2 and 5.1.4 for details.</p>
    860     *
    861     * @param cls  the Class to check, may be null
    862     * @param toClass  the Class to try to assign into, returns false if null
    863     * @param autoboxing  whether to use implicit autoboxing/unboxing between primitives and wrappers
    864     * @return {@code true} if assignment possible
    865     */
    866    public static boolean isAssignable(Class<?> cls, final Class<?> toClass, final boolean autoboxing) {
    867        if (toClass == null) {
    868            return false;
    869        }
    870        // have to check for null, as isAssignableFrom doesn't
    871        if (cls == null) {
    872            return !toClass.isPrimitive();
    873        }
    874        //autoboxing:
    875        if (autoboxing) {
    876            if (cls.isPrimitive() && !toClass.isPrimitive()) {
    877                cls = primitiveToWrapper(cls);
    878                if (cls == null) {
    879                    return false;
    880                }
    881            }
    882            if (toClass.isPrimitive() && !cls.isPrimitive()) {
    883                cls = wrapperToPrimitive(cls);
    884                if (cls == null) {
    885                    return false;
    886                }
    887            }
    888        }
    889        if (cls.equals(toClass)) {
    890            return true;
    891        }
    892        if (cls.isPrimitive()) {
    893            if (!toClass.isPrimitive()) {
    894                return false;
    895            }
    896            if (Integer.TYPE.equals(cls)) {
    897                return Long.TYPE.equals(toClass)
    898                    || Float.TYPE.equals(toClass)
    899                    || Double.TYPE.equals(toClass);
    900            }
    901            if (Long.TYPE.equals(cls)) {
    902                return Float.TYPE.equals(toClass)
    903                    || Double.TYPE.equals(toClass);
    904            }
    905            if (Boolean.TYPE.equals(cls)) {
    906                return false;
    907            }
    908            if (Double.TYPE.equals(cls)) {
    909                return false;
    910            }
    911            if (Float.TYPE.equals(cls)) {
    912                return Double.TYPE.equals(toClass);
    913            }
    914            if (Character.TYPE.equals(cls)) {
    915                return Integer.TYPE.equals(toClass)
    916                    || Long.TYPE.equals(toClass)
    917                    || Float.TYPE.equals(toClass)
    918                    || Double.TYPE.equals(toClass);
    919            }
    920            if (Short.TYPE.equals(cls)) {
    921                return Integer.TYPE.equals(toClass)
    922                    || Long.TYPE.equals(toClass)
    923                    || Float.TYPE.equals(toClass)
    924                    || Double.TYPE.equals(toClass);
    925            }
    926            if (Byte.TYPE.equals(cls)) {
    927                return Short.TYPE.equals(toClass)
    928                    || Integer.TYPE.equals(toClass)
    929                    || Long.TYPE.equals(toClass)
    930                    || Float.TYPE.equals(toClass)
    931                    || Double.TYPE.equals(toClass);
    932            }
    933            // should never get here
    934            return false;
    935        }
    936        return toClass.isAssignableFrom(cls);
    937    }
    938
    939    /**
    940     * <p>Converts the specified primitive Class object to its corresponding
    941     * wrapper Class object.</p>
    942     *
    943     * <p>NOTE: From v2.2, this method handles {@code Void.TYPE},
    944     * returning {@code Void.TYPE}.</p>
    945     *
    946     * @param cls  the class to convert, may be null
    947     * @return the wrapper class for {@code cls} or {@code cls} if
    948     * {@code cls} is not a primitive. {@code null} if null input.
    949     * @since 2.1
    950     */
    951    public static Class<?> primitiveToWrapper(final Class<?> cls) {
    952        Class<?> convertedClass = cls;
    953        if (cls != null && cls.isPrimitive()) {
    954            convertedClass = primitiveWrapperMap.get(cls);
    955        }
    956        return convertedClass;
    957    }
    958
    959    /**
    960     * <p>Converts the specified array of primitive Class objects to an array of
    961     * its corresponding wrapper Class objects.</p>
    962     *
    963     * @param classes  the class array to convert, may be null or empty
    964     * @return an array which contains for each given class, the wrapper class or
    965     * the original class if class is not a primitive. {@code null} if null input.
    966     * Empty array if an empty array passed in.
    967     * @since 2.1
    968     */
    969    public static Class<?>[] primitivesToWrappers(final Class<?>... classes) {
    970        if (classes == null) {
    971            return null;
    972        }
    973
    974        if (classes.length == 0) {
    975            return classes;
    976        }
    977
    978        final Class<?>[] convertedClasses = new Class[classes.length];
    979        for (int i = 0; i < classes.length; i++) {
    980            convertedClasses[i] = primitiveToWrapper(classes[i]);
    981        }
    982        return convertedClasses;
    983    }
    984
    985    /**
    986     * <p>Converts the specified wrapper class to its corresponding primitive
    987     * class.</p>
    988     *
    989     * <p>This method is the counter part of {@code primitiveToWrapper()}.
    990     * If the passed in class is a wrapper class for a primitive type, this
    991     * primitive type will be returned (e.g. {@code Integer.TYPE} for
    992     * {@code Integer.class}). For other classes, or if the parameter is
    993     * <b>null</b>, the return value is <b>null</b>.</p>
    994     *
    995     * @param cls the class to convert, may be <b>null</b>
    996     * @return the corresponding primitive type if {@code cls} is a
    997     * wrapper class, <b>null</b> otherwise
    998     * @see #primitiveToWrapper(Class)
    999     * @since 2.4
    1000     */
    1001    public static Class<?> wrapperToPrimitive(final Class<?> cls) {
    1002        return wrapperPrimitiveMap.get(cls);
    1003    }
    1004
    1005    /**
    1006     * <p>Converts the specified array of wrapper Class objects to an array of
    1007     * its corresponding primitive Class objects.</p>
    1008     *
    1009     * <p>This method invokes {@code wrapperToPrimitive()} for each element
    1010     * of the passed in array.</p>
    1011     *
    1012     * @param classes  the class array to convert, may be null or empty
    1013     * @return an array which contains for each given class, the primitive class or
    1014     * <b>null</b> if the original class is not a wrapper class. {@code null} if null input.
    1015     * Empty array if an empty array passed in.
    1016     * @see #wrapperToPrimitive(Class)
    1017     * @since 2.4
    1018     */
    1019    public static Class<?>[] wrappersToPrimitives(final Class<?>... classes) {
    1020        if (classes == null) {
    1021            return null;
    1022        }
    1023
    1024        if (classes.length == 0) {
    1025            return classes;
    1026        }
    1027
    1028        final Class<?>[] convertedClasses = new Class[classes.length];
    1029        for (int i = 0; i < classes.length; i++) {
    1030            convertedClasses[i] = wrapperToPrimitive(classes[i]);
    1031        }
    1032        return convertedClasses;
    1033    }
    1034
    1035    // Inner class
    1036    // ----------------------------------------------------------------------
    1037    /**
    1038     * <p>Is the specified class an inner class or static nested class.</p>
    1039     *
    1040     * @param cls  the class to check, may be null
    1041     * @return {@code true} if the class is an inner or static nested class,
    1042     *  false if not or {@code null}
    1043     */
    1044    public static boolean isInnerClass(final Class<?> cls) {
    1045        return cls != null && cls.getEnclosingClass() != null;
    1046    }
    1047
    1048    // Class loading
    1049    // ----------------------------------------------------------------------
    1050    /**
    1051     * Returns the class represented by {@code className} using the
    1052     * {@code classLoader}.  This implementation supports the syntaxes
    1053     * "{@code java.util.Map.Entry[]}", "{@code java.util.Map$Entry[]}",
    1054     * "{@code [Ljava.util.Map.Entry;}", and "{@code [Ljava.util.Map$Entry;}".
    1055     *
    1056     * @param classLoader  the class loader to use to load the class
    1057     * @param className  the class name
    1058     * @param initialize  whether the class must be initialized
    1059     * @return the class represented by {@code className} using the {@code classLoader}
    1060     * @throws ClassNotFoundException if the class is not found
    1061     */
    1062    public static Class<?> getClass(
    1063            final ClassLoader classLoader, final String className, final boolean initialize) throws ClassNotFoundException {
    1064        try {
    1065            Class<?> clazz;
    1066            if (namePrimitiveMap.containsKey(className)) {
    1067                clazz = namePrimitiveMap.get(className);
    1068            } else {
    1069                clazz = Class.forName(toCanonicalName(className), initialize, classLoader);
    1070            }
    1071            return clazz;
    1072        } catch (final ClassNotFoundException ex) {
    1073            // allow path separators (.) as inner class name separators
    1074            final int lastDotIndex = className.lastIndexOf(PACKAGE_SEPARATOR_CHAR);
    1075
    1076            if (lastDotIndex != -1) {
    1077                try {
    1078                    return getClass(classLoader, className.substring(0, lastDotIndex) +
    1079                            INNER_CLASS_SEPARATOR_CHAR + className.substring(lastDotIndex + 1),
    1080                            initialize);
    1081                } catch (final ClassNotFoundException ex2) { // NOPMD
    1082                    // ignore exception
    1083                }
    1084            }
    1085
    1086            throw ex;
    1087        }
    1088    }
    1089
    1090    /**
    1091     * Returns the (initialized) class represented by {@code className}
    1092     * using the {@code classLoader}.  This implementation supports
    1093     * the syntaxes "{@code java.util.Map.Entry[]}",
    1094     * "{@code java.util.Map$Entry[]}", "{@code [Ljava.util.Map.Entry;}",
    1095     * and "{@code [Ljava.util.Map$Entry;}".
    1096     *
    1097     * @param classLoader  the class loader to use to load the class
    1098     * @param className  the class name
    1099     * @return the class represented by {@code className} using the {@code classLoader}
    1100     * @throws ClassNotFoundException if the class is not found
    1101     */
    1102    public static Class<?> getClass(final ClassLoader classLoader, final String className) throws ClassNotFoundException {
    1103        return getClass(classLoader, className, true);
    1104    }
    1105
    1106    /**
    1107     * Returns the (initialized) class represented by {@code className}
    1108     * using the current thread's context class loader. This implementation
    1109     * supports the syntaxes "{@code java.util.Map.Entry[]}",
    1110     * "{@code java.util.Map$Entry[]}", "{@code [Ljava.util.Map.Entry;}",
    1111     * and "{@code [Ljava.util.Map$Entry;}".
    1112     *
    1113     * @param className  the class name
    1114     * @return the class represented by {@code className} using the current thread's context class loader
    1115     * @throws ClassNotFoundException if the class is not found
    1116     */
    1117    public static Class<?> getClass(final String className) throws ClassNotFoundException {
    1118        return getClass(className, true);
    1119    }
    1120
    1121    /**
    1122     * Returns the class represented by {@code className} using the
    1123     * current thread's context class loader. This implementation supports the
    1124     * syntaxes "{@code java.util.Map.Entry[]}", "{@code java.util.Map$Entry[]}",
    1125     * "{@code [Ljava.util.Map.Entry;}", and "{@code [Ljava.util.Map$Entry;}".
    1126     *
    1127     * @param className  the class name
    1128     * @param initialize  whether the class must be initialized
    1129     * @return the class represented by {@code className} using the current thread's context class loader
    1130     * @throws ClassNotFoundException if the class is not found
    1131     */
    1132    public static Class<?> getClass(final String className, final boolean initialize) throws ClassNotFoundException {
    1133        final ClassLoader contextCL = Thread.currentThread().getContextClassLoader();
    1134        final ClassLoader loader = contextCL == null ? ClassUtils.class.getClassLoader() : contextCL;
    1135        return getClass(loader, className, initialize);
    1136    }
    1137
    1138    // Public method
    1139    // ----------------------------------------------------------------------
    1140    /**
    1141     * <p>Returns the desired Method much like {@code Class.getMethod}, however
    1142     * it ensures that the returned Method is from a public class or interface and not
    1143     * from an anonymous inner class. This means that the Method is invokable and
    1144     * doesn't fall foul of Java bug
    1145     * <a href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4071957">4071957</a>).</p>
    1146     *
    1147     *  <pre>
    1148     *  <code>Set set = Collections.unmodifiableSet(...);
    1149     *  Method method = ClassUtils.getPublicMethod(set.getClass(), "isEmpty",  new Class[0]);
    1150     *  Object result = method.invoke(set, new Object[]);</code>
    1151     *  </pre>
    1152     *
    1153     * @param cls  the class to check, not null
    1154     * @param methodName  the name of the method
    1155     * @param parameterTypes  the list of parameters
    1156     * @return the method
    1157     * @throws NullPointerException if the class is null
    1158     * @throws SecurityException if a security violation occurred
    1159     * @throws NoSuchMethodException if the method is not found in the given class
    1160     *  or if the method doesn't conform with the requirements
    1161     */
    1162    public static Method getPublicMethod(final Class<?> cls, final String methodName, final Class<?>... parameterTypes)
    1163            throws NoSuchMethodException {
    1164
    1165        final Method declaredMethod = cls.getMethod(methodName, parameterTypes);
    1166        if (Modifier.isPublic(declaredMethod.getDeclaringClass().getModifiers())) {
    1167            return declaredMethod;
    1168        }
    1169
    1170        final List<Class<?>> candidateClasses = new ArrayList<>();
    1171        candidateClasses.addAll(getAllInterfaces(cls));
    1172        candidateClasses.addAll(getAllSuperclasses(cls));
    1173
    1174        for (final Class<?> candidateClass : candidateClasses) {
    1175            if (!Modifier.isPublic(candidateClass.getModifiers())) {
    1176                continue;
    1177            }
    1178            Method candidateMethod;
    1179            try {
    1180                candidateMethod = candidateClass.getMethod(methodName, parameterTypes);
    1181            } catch (final NoSuchMethodException ex) {
    1182                continue;
    1183            }
    1184            if (Modifier.isPublic(candidateMethod.getDeclaringClass().getModifiers())) {
    1185                return candidateMethod;
    1186            }
    1187        }
    1188
    1189        throw new NoSuchMethodException("Can't find a public method for " +
    1190                methodName + " " + ArrayUtils.toString(parameterTypes));
    1191    }
    1192
    1193    // ----------------------------------------------------------------------
    1194    /**
    1195     * Converts a class name to a JLS style class name.
    1196     *
    1197     * @param className  the class name
    1198     * @return the converted name
    1199     */
    1200    private static String toCanonicalName(String className) {
    1201        className = StringUtils.deleteWhitespace(className);
    1202        Validate.notNull(className, "className must not be null.");
    1203        if (className.endsWith("[]")) {
    1204            final StringBuilder classNameBuffer = new StringBuilder();
    1205            while (className.endsWith("[]")) {
    1206                className = className.substring(0, className.length() - 2);
    1207                classNameBuffer.append("[");
    1208            }
    1209            final String abbreviation = abbreviationMap.get(className);
    1210            if (abbreviation != null) {
    1211                classNameBuffer.append(abbreviation);
    1212            } else {
    1213                classNameBuffer.append("L").append(className).append(";");
    1214            }
    1215            className = classNameBuffer.toString();
    1216        }
    1217        return className;
    1218    }
    1219
    1220    /**
    1221     * <p>Converts an array of {@code Object} in to an array of {@code Class} objects.
    1222     * If any of these objects is null, a null element will be inserted into the array.</p>
    1223     *
    1224     * <p>This method returns {@code null} for a {@code null} input array.</p>
    1225     *
    1226     * @param array an {@code Object} array
    1227     * @return a {@code Class} array, {@code null} if null array input
    1228     * @since 2.4
    1229     */
    1230    public static Class<?>[] toClass(final Object... array) {
    1231        if (array == null) {
    1232            return null;
    1233        } else if (array.length == 0) {
    1234            return ArrayUtils.EMPTY_CLASS_ARRAY;
    1235        }
    1236        final Class<?>[] classes = new Class[array.length];
    1237        for (int i = 0; i < array.length; i++) {
    1238            classes[i] = array[i] == null ? null : array[i].getClass();
    1239        }
    1240        return classes;
    1241    }
    1242
    1243    // Short canonical name
    1244    // ----------------------------------------------------------------------
    1245    /**
    1246     * <p>Gets the canonical name minus the package name for an {@code Object}.</p>
    1247     *
    1248     * @param object  the class to get the short name for, may be null
    1249     * @param valueIfNull  the value to return if null
    1250     * @return the canonical name of the object without the package name, or the null value
    1251     * @since 2.4
    1252     */
    1253    public static String getShortCanonicalName(final Object object, final String valueIfNull) {
    1254        if (object == null) {
    1255            return valueIfNull;
    1256        }
    1257        return getShortCanonicalName(object.getClass().getName());
    1258    }
    1259
    1260    /**
    1261     * <p>Gets the canonical class name for a {@code Class}.</p>
    1262     *
    1263     * @param cls the class for which to get the canonical class name; may be null
    1264     * @return the canonical name of the class, or the empty String
    1265     * @since 3.7
    1266     * @see Class#getCanonicalName()
    1267     */
    1268    public static String getCanonicalName(final Class<?> cls) {
    1269        return getCanonicalName(cls, StringUtils.EMPTY);
    1270    }
    1271
    1272    /**
    1273     * <p>Gets the canonical name for a {@code Class}.</p>
    1274     *
    1275     * @param cls the class for which to get the canonical class name; may be null
    1276     * @param valueIfNull  the return value if null
    1277     * @return the canonical name of the class, or {@code valueIfNull}
    1278     * @since 3.7
    1279     * @see Class#getCanonicalName()
    1280     */
    1281    public static String getCanonicalName(final Class<?> cls, final String valueIfNull) {
    1282        if (cls == null) {
    1283            return valueIfNull;
    1284        }
    1285        final String canonicalName = cls.getCanonicalName();
    1286        return canonicalName == null ? valueIfNull : canonicalName;
    1287    }
    1288
    1289    /**
    1290     * <p>Gets the canonical name for an {@code Object}.</p>
    1291     *
    1292     * @param object the object for which to get the canonical class name; may be null
    1293     * @return the canonical name of the object, or the empty String
    1294     * @since 3.7
    1295     * @see Class#getCanonicalName()
    1296     */
    1297    public static String getCanonicalName(final Object object) {
    1298        return getCanonicalName(object, StringUtils.EMPTY);
    1299    }
    1300
    1301    /**
    1302     * <p>Gets the canonical name for an {@code Object}.</p>
    1303     *
    1304     * @param object the object for which to get the canonical class name; may be null
    1305     * @param valueIfNull  the return value if null
    1306     * @return the canonical name of the object or {@code valueIfNull}
    1307     * @since 3.7
    1308     * @see Class#getCanonicalName()
    1309     */
    1310    public static String getCanonicalName(final Object object, final String valueIfNull) {
    1311        if (object == null) {
    1312            return valueIfNull;
    1313        }
    1314        final String canonicalName = object.getClass().getCanonicalName();
    1315        return canonicalName == null ? valueIfNull : canonicalName;
    1316    }
    1317
    1318    /**
    1319     * <p>Gets the canonical name minus the package name from a {@code Class}.</p>
    1320     *
    1321     * @param cls the class for which to get the short canonical class name; may be null
    1322     * @return the canonical name without the package name or an empty string
    1323     * @since 2.4
    1324     */
    1325    public static String getShortCanonicalName(final Class<?> cls) {
    1326        if (cls == null) {
    1327            return StringUtils.EMPTY;
    1328        }
    1329        return getShortCanonicalName(cls.getName());
    1330    }
    1331
    1332    /**
    1333     * <p>Gets the canonical name minus the package name from a String.</p>
    1334     *
    1335     * <p>The string passed in is assumed to be a class name - it is not checked.</p>
    1336     *
    1337     * <p>Note that this method is mainly designed to handle the arrays and primitives properly.
    1338     * If the class is an inner class then the result value will not contain the outer classes.
    1339     * This way the behavior of this method is different from {@link #getShortClassName(String)}.
    1340     * The argument in that case is class name and not canonical name and the return value
    1341     * retains the outer classes.</p>
    1342     *
    1343     * <p>Note that there is no way to reliably identify the part of the string representing the
    1344     * package hierarchy and the part that is the outer class or classes in case of an inner class.
    1345     * Trying to find the class would require reflective call and the class itself may not even be
    1346     * on the class path. Relying on the fact that class names start with capital letter and packages
    1347     * with lower case is heuristic.</p>
    1348     *
    1349     * <p>It is recommended to use {@link #getShortClassName(String)} for cases when the class
    1350     * is an inner class and use this method for cases it is designed for.</p>
    1351     *
    1352     * <table>
    1353     * <caption>Examples</caption>
    1354     * <tr><td>return value</td><td>input</td></tr>
    1355     * <tr><td>{@code ""}</td><td>{@code (String)null}</td></tr>
    1356     * <tr><td>{@code "Map.Entry"}</td><td>{@code java.util.Map.Entry.class.getName()}</td></tr>
    1357     * <tr><td>{@code "Entry"}</td><td>{@code java.util.Map.Entry.class.getCanonicalName()}</td></tr>
    1358     * <tr><td>{@code "ClassUtils"}</td><td>{@code "org.apache.commons.lang3.ClassUtils"}</td></tr>
    1359     * <tr><td>{@code "ClassUtils[]"}</td><td>{@code "[Lorg.apache.commons.lang3.ClassUtils;"}</td></tr>
    1360     * <tr><td>{@code "ClassUtils[][]"}</td><td>{@code "[[Lorg.apache.commons.lang3.ClassUtils;"}</td></tr>
    1361     * <tr><td>{@code "ClassUtils[]"}</td><td>{@code "org.apache.commons.lang3.ClassUtils[]"}</td></tr>
    1362     * <tr><td>{@code "ClassUtils[][]"}</td><td>{@code "org.apache.commons.lang3.ClassUtils[][]"}</td></tr>
    1363     * <tr><td>{@code "int[]"}</td><td>{@code "[I"}</td></tr>
    1364     * <tr><td>{@code "int[]"}</td><td>{@code int[].class.getCanonicalName()}</td></tr>
    1365     * <tr><td>{@code "int[]"}</td><td>{@code int[].class.getName()}</td></tr>
    1366     * <tr><td>{@code "int[][]"}</td><td>{@code "[[I"}</td></tr>
    1367     * <tr><td>{@code "int[]"}</td><td>{@code "int[]"}</td></tr>
    1368     * <tr><td>{@code "int[][]"}</td><td>{@code "int[][]"}</td></tr>
    1369     * </table>
    1370     *
    1371     * @param canonicalName  the class name to get the short name for
    1372     * @return the canonical name of the class without the package name or an empty string
    1373     * @since 2.4
    1374     */
    1375    public static String getShortCanonicalName(final String canonicalName) {
    1376        return getShortClassName(getCanonicalName(canonicalName));
    1377    }
    1378
    1379    // Package name
    1380    // ----------------------------------------------------------------------
    1381    /**
    1382     * <p>Gets the package name from the class name of an {@code Object}.</p>
    1383     *
    1384     * @param object  the class to get the package name for, may be null
    1385     * @param valueIfNull  the value to return if null
    1386     * @return the package name of the object, or the null value
    1387     * @since 2.4
    1388     */
    1389    public static String getPackageCanonicalName(final Object object, final String valueIfNull) {
    1390        if (object == null) {
    1391            return valueIfNull;
    1392        }
    1393        return getPackageCanonicalName(object.getClass().getName());
    1394    }
    1395
    1396    /**
    1397     * <p>Gets the package name from the canonical name of a {@code Class}.</p>
    1398     *
    1399     * @param cls  the class to get the package name for, may be {@code null}.
    1400     * @return the package name or an empty string
    1401     * @since 2.4
    1402     */
    1403    public static String getPackageCanonicalName(final Class<?> cls) {
    1404        if (cls == null) {
    1405            return StringUtils.EMPTY;
    1406        }
    1407        return getPackageCanonicalName(cls.getName());
    1408    }
    1409
    1410    /**
    1411     * <p>Gets the package name from the class name. </p>
    1412     *
    1413     * <p>The string passed in is assumed to be a class name - it is not checked.</p>
    1414     * <p>If the class is in the default package, return an empty string.</p>
    1415     *
    1416     * @param name  the name to get the package name for, may be {@code null}
    1417     * @return the package name or an empty string
    1418     * @since 2.4
    1419     */
    1420    public static String getPackageCanonicalName(final String name) {
    1421        return getPackageName(getCanonicalName(name));
    1422    }
    1423
    1424    /**
    1425     * <p>Converts a given name of class into canonical format.
    1426     * If name of class is not a name of array class it returns
    1427     * unchanged name.</p>
    1428     *
    1429     * <p>The method does not change the {@code $} separators in case
    1430     * the class is inner class.</p>
    1431     *
    1432     * <p>Example:
    1433     * <ul>
    1434     * <li>{@code getCanonicalName("[I") = "int[]"}</li>
    1435     * <li>{@code getCanonicalName("[Ljava.lang.String;") = "java.lang.String[]"}</li>
    1436     * <li>{@code getCanonicalName("java.lang.String") = "java.lang.String"}</li>
    1437     * </ul>
    1438     * </p>
    1439     *
    1440     * @param className the name of class
    1441     * @return canonical form of class name
    1442     * @since 2.4
    1443     */
    1444    private static String getCanonicalName(String className) {
    1445        className = StringUtils.deleteWhitespace(className);
    1446        if (className == null) {
    1447            return null;
    1448        }
    1449        int dim = 0;
    1450        while (className.startsWith("[")) {
    1451            dim++;
    1452            className = className.substring(1);
    1453        }
    1454        if (dim < 1) {
    1455            return className;
    1456        }
    1457        if (className.startsWith("L")) {
    1458            className = className.substring(
    1459                1,
    1460                className.endsWith(";")
    1461                    ? className.length() - 1
    1462                    : className.length());
    1463        } else {
    1464            if (!className.isEmpty()) {
    1465                className = reverseAbbreviationMap.get(className.substring(0, 1));
    1466            }
    1467        }
    1468        final StringBuilder canonicalClassNameBuffer = new StringBuilder(className);
    1469        for (int i = 0; i < dim; i++) {
    1470            canonicalClassNameBuffer.append("[]");
    1471        }
    1472        return canonicalClassNameBuffer.toString();
    1473    }
    1474
    1475    /**
    1476     * Gets an {@link Iterable} that can iterate over a class hierarchy in ascending (subclass to superclass) order,
    1477     * excluding interfaces.
    1478     *
    1479     * @param type the type to get the class hierarchy from
    1480     * @return Iterable an Iterable over the class hierarchy of the given class
    1481     * @since 3.2
    1482     */
    1483    public static Iterable<Class<?>> hierarchy(final Class<?> type) {
    1484        return hierarchy(type, Interfaces.EXCLUDE);
    1485    }
    1486
    1487    /**
    1488     * Gets an {@link Iterable} that can iterate over a class hierarchy in ascending (subclass to superclass) order.
    1489     *
    1490     * @param type the type to get the class hierarchy from
    1491     * @param interfacesBehavior switch indicating whether to include or exclude interfaces
    1492     * @return Iterable an Iterable over the class hierarchy of the given class
    1493     * @since 3.2
    1494     */
    1495    public static Iterable<Class<?>> hierarchy(final Class<?> type, final Interfaces interfacesBehavior) {
    1496        final Iterable<Class<?>> classes = () -> {
    1497            final MutableObject<Class<?>> next = new MutableObject<>(type);
    1498            return new Iterator<Class<?>>() {
    1499
    1500                @Override
    1501                public boolean hasNext() {
    1502                    return next.getValue() != null;
    1503                }
    1504
    1505                @Override
    1506                public Class<?> next() {
    1507                    final Class<?> result = next.getValue();
    1508                    next.setValue(result.getSuperclass());
    1509                    return result;
    1510                }
    1511
    1512                @Override
    1513                public void remove() {
    1514                    throw new UnsupportedOperationException();
    1515                }
    1516
    1517            };
    1518        };
    1519        if (interfacesBehavior != Interfaces.INCLUDE) {
    1520            return classes;
    1521        }
    1522        return () -> {
    1523            final Set<Class<?>> seenInterfaces = new HashSet<>();
    1524            final Iterator<Class<?>> wrapped = classes.iterator();
    1525
    1526            return new Iterator<Class<?>>() {
    1527                Iterator<Class<?>> interfaces = Collections.<Class<?>>emptySet().iterator();
    1528
    1529                @Override
    1530                public boolean hasNext() {
    1531                    return interfaces.hasNext() || wrapped.hasNext();
    1532                }
    1533
    1534                @Override
    1535                public Class<?> next() {
    1536                    if (interfaces.hasNext()) {
    1537                        final Class<?> nextInterface = interfaces.next();
    1538                        seenInterfaces.add(nextInterface);
    1539                        return nextInterface;
    1540                    }
    1541                    final Class<?> nextSuperclass = wrapped.next();
    1542                    final Set<Class<?>> currentInterfaces = new LinkedHashSet<>();
    1543                    walkInterfaces(currentInterfaces, nextSuperclass);
    1544                    interfaces = currentInterfaces.iterator();
    1545                    return nextSuperclass;
    1546                }
    1547
    1548                private void walkInterfaces(final Set<Class<?>> addTo, final Class<?> c) {
    1549                    for (final Class<?> iface : c.getInterfaces()) {
    1550                        if (!seenInterfaces.contains(iface)) {
    1551                            addTo.add(iface);
    1552                        }
    1553                        walkInterfaces(addTo, iface);
    1554                    }
    1555                }
    1556
    1557                @Override
    1558                public void remove() {
    1559                    throw new UnsupportedOperationException();
    1560                }
    1561
    1562            };
    1563        };
    1564    }
    1565
    1566}