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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.apache.commons.lang3.text.translate;
18  
19  import java.io.IOException;
20  import java.io.Writer;
21  
22  /**
23   * Translates code points to their Unicode escaped value.
24   *
25   * @since 3.0
26   * @deprecated As of 3.6, use Apache Commons Text
27   * <a href="https://commons.apache.org/proper/commons-text/javadocs/api-release/org/apache/commons/text/translate/UnicodeEscaper.html">
28   * UnicodeEscaper</a> instead
29   */
30  @Deprecated
31  public class UnicodeEscaper extends CodePointTranslator {
32  
33      /**
34       * Constructs a {@link UnicodeEscaper} above the specified value (exclusive).
35       *
36       * @param codePoint above which to escape
37       * @return the newly created {@link UnicodeEscaper} instance
38       */
39      public static UnicodeEscaper above(final int codePoint) {
40          return outsideOf(0, codePoint);
41      }
42      /**
43       * Constructs a {@link UnicodeEscaper} below the specified value (exclusive).
44       *
45       * @param codePoint below which to escape
46       * @return the newly created {@link UnicodeEscaper} instance
47       */
48      public static UnicodeEscaper below(final int codePoint) {
49          return outsideOf(codePoint, Integer.MAX_VALUE);
50      }
51      /**
52       * Constructs a {@link UnicodeEscaper} between the specified values (inclusive).
53       *
54       * @param codePointLow above which to escape
55       * @param codePointHigh below which to escape
56       * @return the newly created {@link UnicodeEscaper} instance
57       */
58      public static UnicodeEscaper between(final int codePointLow, final int codePointHigh) {
59          return new UnicodeEscaper(codePointLow, codePointHigh, true);
60      }
61  
62      /**
63       * Constructs a {@link UnicodeEscaper} outside of the specified values (exclusive).
64       *
65       * @param codePointLow below which to escape
66       * @param codePointHigh above which to escape
67       * @return the newly created {@link UnicodeEscaper} instance
68       */
69      public static UnicodeEscaper outsideOf(final int codePointLow, final int codePointHigh) {
70          return new UnicodeEscaper(codePointLow, codePointHigh, false);
71      }
72  
73      private final int below;
74  
75      private final int above;
76  
77      private final boolean between;
78  
79      /**
80       * Constructs a {@link UnicodeEscaper} for all characters.
81       */
82      public UnicodeEscaper() {
83          this(0, Integer.MAX_VALUE, true);
84      }
85  
86      /**
87       * Constructs a {@link UnicodeEscaper} for the specified range. This is
88       * the underlying method for the other constructors/builders. The {@code below}
89       * and {@code above} boundaries are inclusive when {@code between} is
90       * {@code true} and exclusive when it is {@code false}.
91       *
92       * @param below int value representing the lowest code point boundary
93       * @param above int value representing the highest code point boundary
94       * @param between whether to escape between the boundaries or outside them
95       */
96      protected UnicodeEscaper(final int below, final int above, final boolean between) {
97          this.below = below;
98          this.above = above;
99          this.between = between;
100     }
101 
102     /**
103      * Converts the given code point to a hexadecimal string of the form {@code "\\uXXXX"}
104      *
105      * @param codePoint
106      *            a Unicode code point
107      * @return the hexadecimal string for the given code point
108      *
109      * @since 3.2
110      */
111     protected String toUtf16Escape(final int codePoint) {
112         return "\\u" + hex(codePoint);
113     }
114 
115     /**
116      * {@inheritDoc}
117      */
118     @Override
119     public boolean translate(final int codePoint, final Writer out) throws IOException {
120         if (between) {
121             if (codePoint < below || codePoint > above) {
122                 return false;
123             }
124         } else if (codePoint >= below && codePoint <= above) {
125             return false;
126         }
127 
128         // TODO: Handle potential + sign per various Unicode escape implementations
129         if (codePoint > 0xffff) {
130             out.write(toUtf16Escape(codePoint));
131         } else {
132           out.write("\\u");
133           out.write(HEX_DIGITS[(codePoint >> 12) & 15]);
134           out.write(HEX_DIGITS[(codePoint >> 8) & 15]);
135           out.write(HEX_DIGITS[(codePoint >> 4) & 15]);
136           out.write(HEX_DIGITS[(codePoint) & 15]);
137         }
138         return true;
139     }
140 }