optionalmetapattern.java

来自「Wicket一个开发Java Web应用程序框架。它使得开发web应用程序变得容」· Java 代码 · 共 80 行

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.wicket.util.parse.metapattern;

import java.util.List;

/**
 * Makes any MetaPattern optional by enclosing the pattern in an optionality expression. The
 * expression will be something equivalent to "(?:<pattern>)?".
 * 
 * @author Jonathan Locke
 */
public final class OptionalMetaPattern extends MetaPattern
{
	private static final long serialVersionUID = 1L;

	/**
	 * Constructor
	 * 
	 * @param pattern
	 */
	public OptionalMetaPattern(final String pattern)
	{
		super(pattern);
	}

	/**
	 * Constructor
	 * 
	 * @param pattern
	 *            MetaPattern to make optional
	 */
	public OptionalMetaPattern(final MetaPattern pattern)
	{
		super(pattern);
	}

	/**
	 * Constructor
	 * 
	 * @param patterns
	 */
	public OptionalMetaPattern(final List patterns)
	{
		super(patterns);
	}

	/**
	 * Constructor
	 * 
	 * @param patterns
	 */
	public OptionalMetaPattern(final MetaPattern[] patterns)
	{
		super(patterns);
	}

	/**
	 * @return String representation of this pattern
	 */
	public String toString()
	{
		return "(?:" + super.toString() + ")?";
	}
}