| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.commons.text.translate; |
| |
| import java.io.IOException; |
| import java.io.Writer; |
| |
| /** |
| * Translates codepoints to their Unicode escaped value. |
| * |
| * @since 1.0 |
| */ |
| public class UnicodeEscaper extends CodePointTranslator { |
| |
| /** int value representing the lowest codepoint boundary. */ |
| private final int below; |
| /** int value representing the highest codepoint boundary. */ |
| private final int above; |
| /** whether to escape between the boundaries or outside them. */ |
| private final boolean between; |
| |
| /** |
| * <p>Constructs a {@code UnicodeEscaper} for all characters. |
| * </p> |
| */ |
| public UnicodeEscaper() { |
| this(0, Integer.MAX_VALUE, true); |
| } |
| |
| /** |
| * <p>Constructs a {@code UnicodeEscaper} for the specified range. This is |
| * the underlying method for the other constructors/builders. The {@code below} |
| * and {@code above} boundaries are inclusive when {@code between} is |
| * {@code true} and exclusive when it is {@code false}. </p> |
| * |
| * @param below int value representing the lowest codepoint boundary |
| * @param above int value representing the highest codepoint boundary |
| * @param between whether to escape between the boundaries or outside them |
| */ |
| protected UnicodeEscaper(final int below, final int above, final boolean between) { |
| this.below = below; |
| this.above = above; |
| this.between = between; |
| } |
| |
| /** |
| * <p>Constructs a {@code UnicodeEscaper} below the specified value (exclusive). </p> |
| * |
| * @param codepoint below which to escape |
| * @return The newly created {@code UnicodeEscaper} instance |
| */ |
| public static UnicodeEscaper below(final int codepoint) { |
| return outsideOf(codepoint, Integer.MAX_VALUE); |
| } |
| |
| /** |
| * <p>Constructs a {@code UnicodeEscaper} above the specified value (exclusive). </p> |
| * |
| * @param codepoint above which to escape |
| * @return The newly created {@code UnicodeEscaper} instance |
| */ |
| public static UnicodeEscaper above(final int codepoint) { |
| return outsideOf(0, codepoint); |
| } |
| |
| /** |
| * <p>Constructs a {@code UnicodeEscaper} outside of the specified values (exclusive). </p> |
| * |
| * @param codepointLow below which to escape |
| * @param codepointHigh above which to escape |
| * @return The newly created {@code UnicodeEscaper} instance |
| */ |
| public static UnicodeEscaper outsideOf(final int codepointLow, final int codepointHigh) { |
| return new UnicodeEscaper(codepointLow, codepointHigh, false); |
| } |
| |
| /** |
| * <p>Constructs a {@code UnicodeEscaper} between the specified values (inclusive). </p> |
| * |
| * @param codepointLow above which to escape |
| * @param codepointHigh below which to escape |
| * @return The newly created {@code UnicodeEscaper} instance |
| */ |
| public static UnicodeEscaper between(final int codepointLow, final int codepointHigh) { |
| return new UnicodeEscaper(codepointLow, codepointHigh, true); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public boolean translate(final int codepoint, final Writer out) throws IOException { |
| if (between) { |
| if (codepoint < below || codepoint > above) { |
| return false; |
| } |
| } else { |
| if (codepoint >= below && codepoint <= above) { |
| return false; |
| } |
| } |
| |
| if (codepoint > 0xffff) { |
| out.write(toUtf16Escape(codepoint)); |
| } else { |
| out.write("\\u"); |
| out.write(HEX_DIGITS[(codepoint >> 12) & 15]); |
| out.write(HEX_DIGITS[(codepoint >> 8) & 15]); |
| out.write(HEX_DIGITS[(codepoint >> 4) & 15]); |
| out.write(HEX_DIGITS[(codepoint) & 15]); |
| } |
| return true; |
| } |
| |
| /** |
| * Converts the given codepoint to a hex string of the form {@code "\\uXXXX"}. |
| * |
| * @param codepoint |
| * a Unicode code point |
| * @return The hex string for the given codepoint |
| * |
| */ |
| protected String toUtf16Escape(final int codepoint) { |
| return "\\u" + hex(codepoint); |
| } |
| } |