patterncacherandom.java

jakarta-oro-2.0.8 正则表达式 引擎 源代码

/*
 * $Id: PatternCacheRandom.java,v 1.7 2003/11/07 20:16:24 dfs Exp $
 *
 * ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2000 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
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 * This software consists of voluntary contributions made by many
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 */


package org.apache.oro.text;

import java.util.*;

import org.apache.oro.text.regex.*;
import org.apache.oro.util.*;

/**
 * This class is a GenericPatternCache subclass implementing a random
 * cache replacement policy.  In other words,
 * patterns are added to the cache until it becomes full.  Once the
 * cache is full, when a new pattern is added to the cache, it replaces
 * a randomly selected pattern in the cache.
 *
 * @version @version@
 * @since 1.0
 * @see GenericPatternCache
 */
public final class PatternCacheRandom extends GenericPatternCache {

  /**
   * Creates a PatternCacheRandom instance with a given cache capacity
   * and initialized to use a given PatternCompiler instance as a pattern
   * compiler.
   * <p>
   * @param capacity  The capacity of the cache.
   * @param compiler  The PatternCompiler to use to compile patterns.
   */
  public PatternCacheRandom(int capacity, PatternCompiler compiler) {
    super(new CacheRandom(capacity), compiler);
  }

  /**
   * Same as:
   * <blockquote><pre>
   * PatternCacheRandom(GenericPatternCache.DEFAULT_CAPACITY, compiler);
   * </pre></blockquote>
   */
  public PatternCacheRandom(PatternCompiler compiler) {
    this(GenericPatternCache.DEFAULT_CAPACITY, compiler);
  }

  /**
   * Same as:
   * <blockquote><pre>
   * PatternCacheRandom(capacity, new Perl5Compiler());
   * </pre></blockquote>
   */
  public PatternCacheRandom(int capacity) {
    this(capacity, new Perl5Compiler());
  }

  /**
   * Same as:
   * <blockquote><pre>
   * PatternCacheRandom(GenericPatternCache.DEFAULT_CAPACITY);
   * </pre></blockquote>
   */
  public PatternCacheRandom() {
    this(GenericPatternCache.DEFAULT_CAPACITY);
  }

}