org.eclipse.virgo.bundlor/src/main/java/org/eclipse/virgo/bundlor/util/PathMatcher.java

/*******************************************************************************
 * Copyright (c) 2008, 2010 VMware Inc.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *   VMware Inc. - initial contribution
 *******************************************************************************/

package org.eclipse.virgo.bundlor.util;

import java.util.Comparator;
import java.util.Map;


/**
 * Strategy interface for <code>String</code>-based path matching.
 *
 * <p>Used by {@link org.springframework.core.io.support.PathMatchingResourcePatternResolver},
 * {@link org.springframework.web.servlet.handler.AbstractUrlHandlerMapping},
 * {@link org.springframework.web.servlet.mvc.multiaction.PropertiesMethodNameResolver},
 * and {@link org.springframework.web.servlet.mvc.WebContentInterceptor}.
 *
 * <p>The default implementation is {@link AntPathMatcher}, supporting the
 * Ant-style pattern syntax.
 *
 * @author Juergen Hoeller
 * @since 1.2
 * @see AntPathMatcher
 */
public interface PathMatcher {

	/**
	 * Does the given <code>path</code> represent a pattern that can be matched
	 * by an implementation of this interface?
	 * <p>If the return value is <code>false</code>, then the {@link #match}
	 * method does not have to be used because direct equality comparisons
	 * on the static path Strings will lead to the same result.
	 * @param path the path String to check
	 * @return <code>true</code> if the given <code>path</code> represents a pattern
	 */
	boolean isPattern(String path);

	/**
	 * Match the given <code>path</code> against the given <code>pattern</code>,
	 * according to this PathMatcher's matching strategy.
	 * @param pattern the pattern to match against
	 * @param path the path String to test
	 * @return <code>true</code> if the supplied <code>path</code> matched,
	 * <code>false</code> if it didn't
	 */
	boolean match(String pattern, String path);

	/**
	 * Match the given <code>path</code> against the corresponding part of the given
	 * <code>pattern</code>, according to this PathMatcher's matching strategy.
	 * <p>Determines whether the pattern at least matches as far as the given base
	 * path goes, assuming that a full path may then match as well.
	 * @param pattern the pattern to match against
	 * @param path the path String to test
	 * @return <code>true</code> if the supplied <code>path</code> matched,
	 * <code>false</code> if it didn't
	 */
	boolean matchStart(String pattern, String path);

	/**
	 * Given a pattern and a full path, determine the pattern-mapped part.
	 * <p>This method is supposed to find out which part of the path is matched
	 * dynamically through an actual pattern, that is, it strips off a statically
	 * defined leading path from the given full path, returning only the actually
	 * pattern-matched part of the path.
	 * <p>For example: For "myroot/*.html" as pattern and "myroot/myfile.html"
	 * as full path, this method should return "myfile.html". The detailed
	 * determination rules are specified to this PathMatcher's matching strategy.
	 * <p>A simple implementation may return the given full path as-is in case
	 * of an actual pattern, and the empty String in case of the pattern not
	 * containing any dynamic parts (i.e. the <code>pattern</code> parameter being
	 * a static path that wouldn't qualify as an actual {@link #isPattern pattern}).
	 * A sophisticated implementation will differentiate between the static parts
	 * and the dynamic parts of the given path pattern.
	 * @param pattern the path pattern
	 * @param path the full path to introspect
	 * @return the pattern-mapped part of the given <code>path</code>
	 * (never <code>null</code>)
	 */
	String extractPathWithinPattern(String pattern, String path);

	/**
	 * Given a pattern and a full path, extract the URI template variables. URI template
	 * variables are expressed through curly brackets ('{' and '}').
	 * <p>For example: For pattern "/hotels/{hotel}" and path "/hotels/1", this method will
	 * return a map containing "hotel"->"1".
	 *
	 * @param pattern the path pattern, possibly containing URI templates
	 * @param path the full path to extract template variables from
	 * @return a map, containing variable names as keys; variables values as values
	 */
	Map<String, String> extractUriTemplateVariables(String pattern, String path);

	/**
	 * Given a full path, returns a {@link Comparator} suitable for sorting patterns in order of explicitness for that path.
	 * <p>The full algorithm used depends on the underlying implementation, but generally, the returned
	 * <code>Comparator</code> will {@linkplain java.util.Collections#sort(java.util.List, java.util.Comparator) sort} a
	 * list so that more specific patterns (for that come before generic patterns.
	 *
	 * @param path the full path to use for comparison
	 * @return a comparator capable of sorting patterns in order of explicitness
	 */
	Comparator<String> getPatternComparator(String path);

	/**
	 * Combines two patterns into a new pattern that is returned.
	 * <p>The full algorithm used for combining the two pattern depends on the underlying implementation.
	 *
	 * @param pattern1 the first pattern
	 * @param pattern2 the second pattern
	 * @return the combination of the two patterns
	 * @throws IllegalArgumentException when the two patterns cannot be combined
	 */
	String combine(String pattern1, String pattern2);
}