    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.text.translate;
    018
    019/**
    020 * Translates codepoints to their Unicode escaped value suitable for Java source.
    021 *
    022 * @since 1.0
    023 */
    024public class JavaUnicodeEscaper extends UnicodeEscaper {
    025
    026    /**
    027     * <p>
    028     * Constructs a <code>JavaUnicodeEscaper</code> above the specified value (exclusive).
    029     * </p>
    030     *
    031     * @param codepoint
    032     *            above which to escape
    033     * @return the newly created {@code UnicodeEscaper} instance
    034     */
    035    public static JavaUnicodeEscaper above(final int codepoint) {
    036        return outsideOf(0, codepoint);
    037    }
    038
    039    /**
    040     * <p>
    041     * Constructs a <code>JavaUnicodeEscaper</code> below the specified value (exclusive).
    042     * </p>
    043     *
    044     * @param codepoint
    045     *            below which to escape
    046     * @return the newly created {@code UnicodeEscaper} instance
    047     */
    048    public static JavaUnicodeEscaper below(final int codepoint) {
    049        return outsideOf(codepoint, Integer.MAX_VALUE);
    050    }
    051
    052    /**
    053     * <p>
    054     * Constructs a <code>JavaUnicodeEscaper</code> between the specified values (inclusive).
    055     * </p>
    056     *
    057     * @param codepointLow
    058     *            above which to escape
    059     * @param codepointHigh
    060     *            below which to escape
    061     * @return the newly created {@code UnicodeEscaper} instance
    062     */
    063    public static JavaUnicodeEscaper between(final int codepointLow, final int codepointHigh) {
    064        return new JavaUnicodeEscaper(codepointLow, codepointHigh, true);
    065    }
    066
    067    /**
    068     * <p>
    069     * Constructs a <code>JavaUnicodeEscaper</code> outside of the specified values (exclusive).
    070     * </p>
    071     *
    072     * @param codepointLow
    073     *            below which to escape
    074     * @param codepointHigh
    075     *            above which to escape
    076     * @return the newly created {@code UnicodeEscaper} instance
    077     */
    078    public static JavaUnicodeEscaper outsideOf(final int codepointLow, final int codepointHigh) {
    079        return new JavaUnicodeEscaper(codepointLow, codepointHigh, false);
    080    }
    081
    082    /**
    083     * <p>
    084     * Constructs a <code>JavaUnicodeEscaper</code> for the specified range. This is the underlying method for the
    085     * other constructors/builders. The <code>below</code> and <code>above</code> boundaries are inclusive when
    086     * <code>between</code> is <code>true</code> and exclusive when it is <code>false</code>.
    087     * </p>
    088     *
    089     * @param below
    090     *            int value representing the lowest codepoint boundary
    091     * @param above
    092     *            int value representing the highest codepoint boundary
    093     * @param between
    094     *            whether to escape between the boundaries or outside them
    095     */
    096    public JavaUnicodeEscaper(final int below, final int above, final boolean between) {
    097        super(below, above, between);
    098    }
    099
    100    /**
    101     * Converts the given codepoint to a hex string of the form {@code "\\uXXXX\\uXXXX"}.
    102     *
    103     * @param codepoint
    104     *            a Unicode code point
    105     * @return the hex string for the given codepoint
    106     */
    107    @Override
    108    protected String toUtf16Escape(final int codepoint) {
    109        final char[] surrogatePair = Character.toChars(codepoint);
    110        return "\\u" + hex(surrogatePair[0]) + "\\u" + hex(surrogatePair[1]);
    111    }
    112
    113}