/*
 * Copyright (c) 2007 BUSINESS OBJECTS SOFTWARE LIMITED
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 *     * Redistributions of source code must retain the above copyright notice,
 *       this list of conditions and the following disclaimer.
 *  
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *  
 *     * Neither the name of Business Objects nor the names of its contributors
 *       may be used to endorse or promote products derived from this software
 *       without specific prior written permission.
 *  
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */


/*
 * RegExpBasedUnqualifiedNameFilter.java
 * Creation date: Oct 14, 2005.
 * By: Joseph Wong
 */
package org.openquark.cal.filter;

import java.util.regex.Pattern;

import org.openquark.cal.compiler.QualifiedName;


/**
 * A qualified name filter based on a regular expression pattern. The filter can be configured to either
 * include only those qualified names whose unqualified components match the pattern, or to exclude these matches.
 *
 * @author Joseph Wong
 */
public final class RegExpBasedUnqualifiedNameFilter implements QualifiedNameFilter {
    
    /** The regular expression pattern. */
    private final Pattern entityNamePattern;
    
    /** Whether the filter should accept or reject the matches. */
    private final boolean filterShouldAcceptMatches;
    
    /**
     * Constructs an instance of this filter.
     * @param entityNameRegExp the regular expression pattern.
     * @param isExcludeFilter true if this filter is to work in exclusion mode; false if this filter is to work in include-only mode.
     */
    public RegExpBasedUnqualifiedNameFilter(final String entityNameRegExp, boolean isExcludeFilter) {
        if (entityNameRegExp == null) {
            throw new NullPointerException();
        }
        
        entityNamePattern = Pattern.compile(entityNameRegExp);
        filterShouldAcceptMatches = !isExcludeFilter;
    }

    /**
     * {@inheritDoc}
     */
    public boolean acceptQualifiedName(final QualifiedName qualifiedName) {
        return entityNamePattern.matcher(qualifiedName.getUnqualifiedName()).matches() == filterShouldAcceptMatches;
    }
}