org.apache.commons.text.translate.UnicodeEscaper Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of commons-text Show documentation
Show all versions of commons-text Show documentation
Apache Commons Text is a library focused on algorithms working on strings.
The newest version!
/*
* 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 code points to their Unicode escaped value.
*
* @since 1.0
*/
public class UnicodeEscaper extends CodePointTranslator {
/**
* Constructs a {@code UnicodeEscaper} above the specified value (exclusive).
*
* @param codePoint above which to escape
* @return The newly created {@code UnicodeEscaper} instance
*/
public static UnicodeEscaper above(final int codePoint) {
return outsideOf(0, codePoint);
}
/**
* Constructs a {@code UnicodeEscaper} below the specified value (exclusive).
*
* @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);
}
/**
* Constructs a {@code UnicodeEscaper} between the specified values (inclusive).
*
* @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);
}
/**
* Constructs a {@code UnicodeEscaper} outside of the specified values (exclusive).
*
* @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);
}
/** The lowest code point boundary. */
private final int below;
/** The highest code point boundary. */
private final int above;
/** Whether to escape between the boundaries or outside them. */
private final boolean between;
/**
* Constructs a {@code UnicodeEscaper} for all characters.
*/
public UnicodeEscaper() {
this(0, Integer.MAX_VALUE, true);
}
/**
* 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}.
*
* @param below int value representing the lowest code point boundary
* @param above int value representing the highest code point 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;
}
/**
* Converts the given code point to a hexadecimal string of the form {@code "\\uXXXX"}.
*
* @param codePoint
* a Unicode code point
* @return The hexadecimal string for the given code point
*/
protected String toUtf16Escape(final int codePoint) {
return "\\u" + hex(codePoint);
}
/**
* {@inheritDoc}
*/
@Override
public boolean translate(final int codePoint, final Writer writer) throws IOException {
if (between) {
if (codePoint < below || codePoint > above) {
return false;
}
} else if (codePoint >= below && codePoint <= above) {
return false;
}
if (codePoint > 0xffff) {
writer.write(toUtf16Escape(codePoint));
} else {
writer.write("\\u");
writer.write(HEX_DIGITS[codePoint >> 12 & 15]);
writer.write(HEX_DIGITS[codePoint >> 8 & 15]);
writer.write(HEX_DIGITS[codePoint >> 4 & 15]);
writer.write(HEX_DIGITS[codePoint & 15]);
}
return true;
}
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy