    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.bcel.classfile;
    018
    019import java.io.DataInput;
    020import java.io.DataOutputStream;
    021import java.io.IOException;
    022import java.util.ArrayList;
    023import java.util.List;
    024import java.util.stream.Stream;
    025
    026import org.apache.commons.lang3.stream.Streams;
    027
    028/**
    029 * Represents one annotation in the annotation table
    030 *
    031 * @since 6.0
    032 */
    033public class AnnotationEntry implements Node {
    034
    035    public static final AnnotationEntry[] EMPTY_ARRAY = {};
    036
    037    public static AnnotationEntry[] createAnnotationEntries(final Attribute[] attributes) {
    038        // Find attributes that contain annotation data
    039        return Streams.of(attributes).filter(Annotations.class::isInstance).flatMap(e -> Stream.of(((Annotations) e).getAnnotationEntries()))
    040                .toArray(AnnotationEntry[]::new);
    041    }
    042
    043    /**
    044     * Factory method to create an AnnotionEntry from a DataInput
    045     *
    046     * @param input
    047     * @param constantPool
    048     * @param isRuntimeVisible
    049     * @return the entry
    050     * @throws IOException if an I/O error occurs.
    051     */
    052    public static AnnotationEntry read(final DataInput input, final ConstantPool constantPool, final boolean isRuntimeVisible) throws IOException {
    053        final AnnotationEntry annotationEntry = new AnnotationEntry(input.readUnsignedShort(), constantPool, isRuntimeVisible);
    054        final int numElementValuePairs = input.readUnsignedShort();
    055        for (int i = 0; i < numElementValuePairs; i++) {
    056            annotationEntry.elementValuePairs
    057                .add(new ElementValuePair(input.readUnsignedShort(), ElementValue.readElementValue(input, constantPool), constantPool));
    058        }
    059        return annotationEntry;
    060    }
    061
    062    private final int typeIndex;
    063
    064    private final ConstantPool constantPool;
    065
    066    private final boolean isRuntimeVisible;
    067
    068    private final List<ElementValuePair> elementValuePairs;
    069
    070    public AnnotationEntry(final int typeIndex, final ConstantPool constantPool, final boolean isRuntimeVisible) {
    071        this.typeIndex = typeIndex;
    072        this.constantPool = constantPool;
    073        this.isRuntimeVisible = isRuntimeVisible;
    074        this.elementValuePairs = new ArrayList<>();
    075    }
    076
    077    /**
    078     * Called by objects that are traversing the nodes of the tree implicitly defined by the contents of a Java class.
    079     * I.e., the hierarchy of methods, fields, attributes, etc. spawns a tree of objects.
    080     *
    081     * @param v Visitor object
    082     */
    083    @Override
    084    public void accept(final Visitor v) {
    085        v.visitAnnotationEntry(this);
    086    }
    087
    088    public void addElementNameValuePair(final ElementValuePair elementNameValuePair) {
    089        elementValuePairs.add(elementNameValuePair);
    090    }
    091
    092    public void dump(final DataOutputStream dos) throws IOException {
    093        dos.writeShort(typeIndex); // u2 index of type name in cpool
    094        dos.writeShort(elementValuePairs.size()); // u2 element_value pair
    095        // count
    096        for (final ElementValuePair envp : elementValuePairs) {
    097            envp.dump(dos);
    098        }
    099    }
    100
    101    /**
    102     * @return the annotation type name
    103     */
    104    public String getAnnotationType() {
    105        return constantPool.getConstantUtf8(typeIndex).getBytes();
    106    }
    107
    108    /**
    109     * @return the annotation type index
    110     */
    111    public int getAnnotationTypeIndex() {
    112        return typeIndex;
    113    }
    114
    115    public ConstantPool getConstantPool() {
    116        return constantPool;
    117    }
    118
    119    /**
    120     * @return the element value pairs in this annotation entry
    121     */
    122    public ElementValuePair[] getElementValuePairs() {
    123        // TODO return List
    124        return elementValuePairs.toArray(ElementValuePair.EMPTY_ARRAY);
    125    }
    126
    127    /**
    128     * @return the number of element value pairs in this annotation entry
    129     */
    130    public final int getNumElementValuePairs() {
    131        return elementValuePairs.size();
    132    }
    133
    134    public int getTypeIndex() {
    135        return typeIndex;
    136    }
    137
    138    public boolean isRuntimeVisible() {
    139        return isRuntimeVisible;
    140    }
    141
    142    public String toShortString() {
    143        final StringBuilder result = new StringBuilder();
    144        result.append("@");
    145        result.append(getAnnotationType());
    146        final ElementValuePair[] evPairs = getElementValuePairs();
    147        if (evPairs.length > 0) {
    148            result.append("(");
    149            for (final ElementValuePair element : evPairs) {
    150                result.append(element.toShortString());
    151                result.append(", ");
    152            }
    153            // remove last ", "
    154            result.setLength(result.length() - 2);
    155            result.append(")");
    156        }
    157        return result.toString();
    158    }
    159
    160    @Override
    161    public String toString() {
    162        return toShortString();
    163    }
    164}