001: /*
002: * $Id: PatternCacheLRU.java,v 1.7 2003/11/07 20:16:24 dfs Exp $
003: *
004: * ====================================================================
005: * The Apache Software License, Version 1.1
006: *
007: * Copyright (c) 2000 The Apache Software Foundation. All rights
008: * reserved.
009: *
010: * Redistribution and use in source and binary forms, with or without
011: * modification, are permitted provided that the following conditions
012: * are met:
013: *
014: * 1. Redistributions of source code must retain the above copyright
015: * notice, this list of conditions and the following disclaimer.
016: *
017: * 2. Redistributions in binary form must reproduce the above copyright
018: * notice, this list of conditions and the following disclaimer in
019: * the documentation and/or other materials provided with the
020: * distribution.
021: *
022: * 3. The end-user documentation included with the redistribution,
023: * if any, must include the following acknowledgment:
024: * "This product includes software developed by the
025: * Apache Software Foundation (http://www.apache.org/)."
026: * Alternately, this acknowledgment may appear in the software itself,
027: * if and wherever such third-party acknowledgments normally appear.
028: *
029: * 4. The names "Apache" and "Apache Software Foundation", "Jakarta-Oro"
030: * must not be used to endorse or promote products derived from this
031: * software without prior written permission. For written
032: * permission, please contact apache@apache.org.
033: *
034: * 5. Products derived from this software may not be called "Apache"
035: * or "Jakarta-Oro", nor may "Apache" or "Jakarta-Oro" appear in their
036: * name, without prior written permission of the Apache Software Foundation.
037: *
038: * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
039: * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
040: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
041: * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
042: * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
043: * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
044: * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
045: * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
046: * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
047: * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
048: * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
049: * SUCH DAMAGE.
050: * ====================================================================
051: *
052: * This software consists of voluntary contributions made by many
053: * individuals on behalf of the Apache Software Foundation. For more
054: * information on the Apache Software Foundation, please see
055: * <http://www.apache.org/>.
056: */
057:
058: package org.apache.oro.text;
059:
060: import java.util.*;
061:
062: import org.apache.oro.text.regex.*;
063: import org.apache.oro.util.*;
064:
065: /**
066: * This class is a GenericPatternCache subclass implementing an LRU
067: * (Least Recently Used) cache replacement policy. In other words,
068: * patterns are added to the cache until it becomes full. Once the
069: * cache is full, when a new pattern is added to the cache, it replaces
070: * the least recently used pattern currently in the cache. This is probably
071: * the best general purpose pattern cache replacement policy.
072: *
073: * @version @version@
074: * @since 1.0
075: * @see GenericPatternCache
076: */
077: public final class PatternCacheLRU extends GenericPatternCache {
078:
079: /**
080: * Creates a PatternCacheLRU instance with a given cache capacity,
081: * and initialized to use a given PatternCompiler instance as a pattern
082: * compiler.
083: * <p>
084: * @param capacity The capacity of the cache.
085: * @param compiler The PatternCompiler to use to compile patterns.
086: */
087: public PatternCacheLRU(int capacity, PatternCompiler compiler) {
088: super (new CacheLRU(capacity), compiler);
089: }
090:
091: /**
092: * Same as:
093: * <blockquote><pre>
094: * PatternCacheLRU(GenericPatternCache.DEFAULT_CAPACITY, compiler);
095: * </pre></blockquote>
096: */
097: public PatternCacheLRU(PatternCompiler compiler) {
098: this (GenericPatternCache.DEFAULT_CAPACITY, compiler);
099: }
100:
101: /**
102: * Same as:
103: * <blockquote><pre>
104: * PatternCacheLRU(capacity, new Perl5Compiler());
105: * </pre></blockquote>
106: */
107: public PatternCacheLRU(int capacity) {
108: this (capacity, new Perl5Compiler());
109: }
110:
111: /**
112: * Same as:
113: * <blockquote><pre>
114: * PatternCacheLRU(GenericPatternCache.DEFAULT_CAPACITY);
115: * </pre></blockquote>
116: */
117: public PatternCacheLRU() {
118: this(GenericPatternCache.DEFAULT_CAPACITY);
119: }
120:
121: }
|