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soft-an03/sources/src/main/java/org/apache/commons/text/translate/JavaUnicodeEscaper.java

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Java

/*
* 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;
/**
* Translates code points to their Unicode escaped value suitable for Java source.
*
* @since 1.0
*/
public class JavaUnicodeEscaper extends UnicodeEscaper {
/**
* Constructs a {@code JavaUnicodeEscaper} above the specified value (exclusive).
*
* @param codePoint
* above which to escape
* @return The newly created {@code UnicodeEscaper} instance
*/
public static JavaUnicodeEscaper above(final int codePoint) {
return outsideOf(0, codePoint);
}
/**
* Constructs a {@code JavaUnicodeEscaper} below the specified value (exclusive).
*
* @param codePoint
* below which to escape
* @return The newly created {@code UnicodeEscaper} instance
*/
public static JavaUnicodeEscaper below(final int codePoint) {
return outsideOf(codePoint, Integer.MAX_VALUE);
}
/**
* Constructs a {@code JavaUnicodeEscaper} 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 JavaUnicodeEscaper between(final int codePointLow, final int codePointHigh) {
return new JavaUnicodeEscaper(codePointLow, codePointHigh, true);
}
/**
* Constructs a {@code JavaUnicodeEscaper} 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 JavaUnicodeEscaper outsideOf(final int codePointLow, final int codePointHigh) {
return new JavaUnicodeEscaper(codePointLow, codePointHigh, false);
}
/**
* Constructs a {@code JavaUnicodeEscaper} 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
*/
public JavaUnicodeEscaper(final int below, final int above, final boolean between) {
super(below, above, between);
}
/**
* Converts the given code point to a hex string of the form {@code "\\uXXXX\\uXXXX"}.
*
* @param codePoint
* a Unicode code point
* @return The hex string for the given code point
*/
@Override
protected String toUtf16Escape(final int codePoint) {
final char[] surrogatePair = Character.toChars(codePoint);
assert surrogatePair.length == 1 || surrogatePair.length == 2:
"@AssumeAssertion(index): assertion matches the implementation of Character.toChars";
if (surrogatePair.length == 1) {
throw new IllegalStateException("Expecting codepoint not to be a BMP (1 char) codepoint");
}
return "\\u" + hex(surrogatePair[0]) + "\\u" + hex(surrogatePair[1]);
}
}