You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
78 lines
2.1 KiB
78 lines
2.1 KiB
/*
|
|
* Copyright (C) 2010 The Libphonenumber Authors
|
|
*
|
|
* Licensed 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 com.google.i18n.phonenumbers;
|
|
|
|
import java.util.LinkedHashMap;
|
|
import java.util.Map;
|
|
import java.util.regex.Pattern;
|
|
|
|
/**
|
|
* LRU Cache for compiled regular expressions used by the libphonenumbers libary.
|
|
*
|
|
* @author Shaopeng Jia
|
|
*/
|
|
public class RegexCache {
|
|
private LRUCache<String, Pattern> cache;
|
|
|
|
public RegexCache(int size) {
|
|
cache = new LRUCache<String, Pattern>(size);
|
|
}
|
|
|
|
public Pattern getPatternForRegex(String regex) {
|
|
Pattern pattern = cache.get(regex);
|
|
if (pattern == null) {
|
|
pattern = Pattern.compile(regex);
|
|
cache.put(regex, pattern);
|
|
}
|
|
return pattern;
|
|
}
|
|
|
|
// This method is used for testing.
|
|
boolean containsRegex(String regex) {
|
|
return cache.containsKey(regex);
|
|
}
|
|
|
|
private static class LRUCache<K, V> {
|
|
// LinkedHashMap offers a straightforward implementation of LRU cache.
|
|
private LinkedHashMap<K, V> map;
|
|
private int size;
|
|
|
|
@SuppressWarnings("serial")
|
|
public LRUCache(int size) {
|
|
this.size = size;
|
|
map = new LinkedHashMap<K, V>(size * 4 / 3 + 1, 0.75f, true) {
|
|
@Override
|
|
protected boolean removeEldestEntry(Map.Entry<K, V> eldest) {
|
|
return size() > LRUCache.this.size;
|
|
}
|
|
};
|
|
}
|
|
|
|
public synchronized V get(K key) {
|
|
return map.get(key);
|
|
}
|
|
|
|
public synchronized void put(K key, V value) {
|
|
map.put(key, value);
|
|
}
|
|
|
|
public synchronized boolean containsKey(K key) {
|
|
return map.containsKey(key);
|
|
}
|
|
}
|
|
}
|
|
|