/* |
|
* 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.lang3.text.translate; |
|
import java.io.IOException; |
|
import java.io.Writer; |
|
import java.util.HashMap; |
|
import java.util.HashSet; |
|
/** |
|
* Translates a value using a lookup table. |
|
* |
|
* @since 3.0 |
|
* @deprecated as of 3.6, use commons-text |
|
* <a href="https://commons.apache.org/proper/commons-text/javadocs/api-release/org/apache/commons/text/translate/LookupTranslator.html"> |
|
* LookupTranslator</a> instead |
|
*/ |
|
@Deprecated |
|
public class LookupTranslator extends CharSequenceTranslator { |
|
private final HashMap<String, String> lookupMap; |
|
private final HashSet<Character> prefixSet; |
|
private final int shortest; |
|
private final int longest; |
|
/** |
|
* Define the lookup table to be used in translation |
|
* |
|
* Note that, as of Lang 3.1, the key to the lookup table is converted to a |
|
* java.lang.String. This is because we need the key to support hashCode and |
|
* equals(Object), allowing it to be the key for a HashMap. See LANG-882. |
|
* |
|
* @param lookup CharSequence[][] table of size [*][2] |
|
*/ |
|
public LookupTranslator(final CharSequence[]... lookup) { |
|
lookupMap = new HashMap<>(); |
|
prefixSet = new HashSet<>(); |
|
int _shortest = Integer.MAX_VALUE; |
|
int _longest = 0; |
|
if (lookup != null) { |
|
for (final CharSequence[] seq : lookup) { |
|
this.lookupMap.put(seq[0].toString(), seq[1].toString()); |
|
this.prefixSet.add(seq[0].charAt(0)); |
|
final int sz = seq[0].length(); |
|
if (sz < _shortest) { |
|
_shortest = sz; |
|
} |
|
if (sz > _longest) { |
|
_longest = sz; |
|
} |
|
} |
|
} |
|
shortest = _shortest; |
|
longest = _longest; |
|
} |
|
/** |
|
* {@inheritDoc} |
|
*/ |
|
@Override |
|
public int translate(final CharSequence input, final int index, final Writer out) throws IOException { |
|
// check if translation exists for the input at position index |
|
if (prefixSet.contains(input.charAt(index))) { |
|
int max = longest; |
|
if (index + longest > input.length()) { |
|
max = input.length() - index; |
|
} |
|
// implement greedy algorithm by trying maximum match first |
|
for (int i = max; i >= shortest; i--) { |
|
final CharSequence subSeq = input.subSequence(index, index + i); |
|
final String result = lookupMap.get(subSeq.toString()); |
|
if (result != null) { |
|
out.write(result); |
|
return i; |
|
} |
|
} |
|
} |
|
return 0; |
|
} |
|
} |