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
019import java.io.IOException;
020import java.io.Writer;
021
022import org.apache.commons.lang3.Range;
023
024/**
025 * Translates code points to their XML numeric entity escaped value.
026 *
027 * @since 1.0
028 */
029public class NumericEntityEscaper extends CodePointTranslator {
030
031    /**
032     * Constructs a {@code NumericEntityEscaper} above the specified value (exclusive).
033     *
034     * @param codePoint above which to escape
035     * @return The newly created {@code NumericEntityEscaper} instance
036     */
037    public static NumericEntityEscaper above(final int codePoint) {
038        return outsideOf(0, codePoint);
039    }
040
041    /**
042     * Constructs a {@code NumericEntityEscaper} below the specified value (exclusive).
043     *
044     * @param codePoint below which to escape
045     * @return The newly created {@code NumericEntityEscaper} instance
046     */
047    public static NumericEntityEscaper below(final int codePoint) {
048        return outsideOf(codePoint, Integer.MAX_VALUE);
049    }
050
051    /**
052     * Constructs a {@code NumericEntityEscaper} between the specified values (inclusive).
053     *
054     * @param codePointLow above which to escape
055     * @param codePointHigh below which to escape
056     * @return The newly created {@code NumericEntityEscaper} instance
057     */
058    public static NumericEntityEscaper between(final int codePointLow, final int codePointHigh) {
059        return new NumericEntityEscaper(codePointLow, codePointHigh, true);
060    }
061
062    /**
063     * Constructs a {@code NumericEntityEscaper} outside of the specified values (exclusive).
064     *
065     * @param codePointLow below which to escape
066     * @param codePointHigh above which to escape
067     * @return The newly created {@code NumericEntityEscaper} instance
068     */
069    public static NumericEntityEscaper outsideOf(final int codePointLow, final int codePointHigh) {
070        return new NumericEntityEscaper(codePointLow, codePointHigh, false);
071    }
072
073    /** Whether to escape between the boundaries or outside them. */
074    private final boolean between;
075
076    /** Range from lowest code point to highest code point. */
077    private final Range<Integer> range;
078
079    /**
080     * Constructs a {@code NumericEntityEscaper} for all characters.
081     */
082    public NumericEntityEscaper() {
083        this(0, Integer.MAX_VALUE, true);
084    }
085
086    /**
087     * Constructs a {@code NumericEntityEscaper} for the specified range. This is
088     * the underlying method for the other constructors/builders. The {@code below}
089     * and {@code above} boundaries are inclusive when {@code between} is
090     * {@code true} and exclusive when it is {@code false}.
091     *
092     * @param below int value representing the lowest code point boundary
093     * @param above int value representing the highest code point boundary
094     * @param between whether to escape between the boundaries or outside them
095     */
096    private NumericEntityEscaper(final int below, final int above, final boolean between) {
097        this.range = Range.of(below, above);
098        this.between = between;
099    }
100
101    /**
102     * {@inheritDoc}
103     */
104    @Override
105    public boolean translate(final int codePoint, final Writer writer) throws IOException {
106        if (this.between != this.range.contains(codePoint)) {
107            return false;
108        }
109        writer.write("&#");
110        writer.write(Integer.toString(codePoint, 10));
111        writer.write(';');
112        return true;
113    }
114}