org.helios.tsdb.plugins.util.bloom.AbstractRegexBackedBloom.java Source code

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Here is the source code for org.helios.tsdb.plugins.util.bloom.AbstractRegexBackedBloom.java

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/**
 * Helios, OpenSource Monitoring
 * Brought to you by the Helios Development Group
 *
 * Copyright 2014, Helios Development Group and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org. 
 *
 */
package org.helios.tsdb.plugins.util.bloom;

import java.util.regex.Pattern;

import com.google.common.hash.Funnel;
import com.google.common.hash.PrimitiveSink;

/**
 * <p>Title: AbstractRegexBackedBloom</p>
 * <p>Description: </p> 
 * <p>Company: Helios Development Group LLC</p>
 * @author Whitehead (nwhitehead AT heliosdev DOT org)
 * <p><code>org.helios.tsdb.plugins.util.bloom.AbstractRegexBackedBloom</code></p>
 * @param <T> The type being indexed
 */

public abstract class AbstractRegexBackedBloom<T> implements Funnel<T>, RegexIndexable<T> {
    /** The number of expected insertions to the constructed UnsafeBloomFilter<T> */
    protected final int expectedInsertions;
    /** The desired false positive probability (must be positive and less than 1.0) */
    protected final double fpp;
    /** The unsafe bloom filter */
    protected final UnsafeBloomFilter<T> filter;
    /** The underlying pattern matcher */
    protected final Pattern pattern;

    /**  */
    private static final long serialVersionUID = -4385713292301675664L;

    /** The default false positive probability */
    public static final double DEFAULT_FPP = 0.03;

    /**
     * Creates a new AbstractRegexBackedBloom
     * @param expectedInsertions the number of expected insertions to the constructed UnsafeBloomFilter<T>; must be positive
     * @param fpp the desired false positive probability (must be positive and less than 1.0)
     * @param pattern The underlying pattern matcher
     */
    public AbstractRegexBackedBloom(int expectedInsertions, double fpp, Pattern pattern) {
        this.expectedInsertions = expectedInsertions;
        this.fpp = fpp;
        this.pattern = pattern;
        filter = UnsafeBloomFilter.create(this, this.expectedInsertions, this.fpp);
    }

    /**
     * Creates a new AbstractRegexBackedBloom
     * @param expectedInsertions the number of expected insertions to the constructed UnsafeBloomFilter<T>; must be positive
     * @param fpp the desired false positive probability (must be positive and less than 1.0)
     * @param pattern The underlying pattern matcher
     */
    public AbstractRegexBackedBloom(int expectedInsertions, double fpp, CharSequence pattern) {
        this(expectedInsertions, fpp, Pattern.compile(pattern.toString()));
    }

    /**
     * Creates a new AbstractRegexBackedBloom using the default false positive probability
     * @param expectedInsertions the number of expected insertions to the constructed UnsafeBloomFilter<T>; must be positive
     * @param pattern The underlying pattern matcher
     */
    public AbstractRegexBackedBloom(int expectedInsertions, Pattern pattern) {
        this(expectedInsertions, DEFAULT_FPP, pattern);
    }

    /**
     * Creates a new AbstractRegexBackedBloom using the default false positive probability
     * @param expectedInsertions the number of expected insertions to the constructed UnsafeBloomFilter<T>; must be positive
     * @param pattern The underlying pattern matcher
     */
    public AbstractRegexBackedBloom(int expectedInsertions, CharSequence pattern) {
        this(expectedInsertions, Pattern.compile(pattern.toString()));
    }

    /**
     * {@inheritDoc}
     * @see com.google.common.hash.Funnel#funnel(java.lang.Object, com.google.common.hash.PrimitiveSink)
     */
    @Override
    public abstract void funnel(T from, PrimitiveSink into);

    /**
     * {@inheritDoc}
     * @see org.helios.tsdb.plugins.util.bloom.RegexIndexable#expression(java.lang.Object)
     */
    @Override
    public abstract CharSequence expression(T t);

}