reactor.bus.selector.UriPathTemplate Maven / Gradle / Ivy
/*
* Copyright (c) 2011-2014 Pivotal Software, Inc.
*
* Licensed 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 reactor.bus.selector;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* Represents a URI template. A URI template is a URI-like String that contains variables enclosed by braces
* ({, }), which can be expanded to produce an actual URI.
*
* @author Arjen Poutsma
* @author Juergen Hoeller
* @author Jon Brisbin
* @see URI Templates
*/
public class UriPathTemplate {
private static final Pattern FULL_SPLAT_PATTERN = Pattern.compile("[\\*][\\*]");
private static final String FULL_SPLAT_REPLACEMENT = ".*";
private static final Pattern NAME_SPLAT_PATTERN = Pattern.compile("\\{([^/]+?)\\}[\\*][\\*]");
// JDK 6 doesn't support named capture groups
private static final String NAME_SPLAT_REPLACEMENT = "(?<%NAME%>.*)";
//private static final String NAME_SPLAT_REPLACEMENT = "(.*)";
private static final Pattern NAME_PATTERN = Pattern.compile("\\{([^/]+?)\\}");
// JDK 6 doesn't support named capture groups
private static final String NAME_REPLACEMENT = "(?<%NAME%>[^\\/.]*)";
//private static final String NAME_REPLACEMENT = "([^\\/.]*)";
private final List pathVariables = new ArrayList();
private final HashMap matchers = new HashMap();
private final HashMap> vars = new HashMap>();
private final Pattern uriPattern;
/**
* Creates a new {@code UriPathTemplate} from the given {@code uriPattern}.
*
* @param uriPattern The pattern to be used by the template
*/
public UriPathTemplate(String uriPattern) {
String s = "^" + uriPattern;
Matcher m = NAME_SPLAT_PATTERN.matcher(s);
while (m.find()) {
for (int i = 1; i <= m.groupCount(); i++) {
String name = m.group(i);
pathVariables.add(name);
s = m.replaceFirst(NAME_SPLAT_REPLACEMENT.replaceAll("%NAME%", name));
m.reset(s);
}
}
m = NAME_PATTERN.matcher(s);
while (m.find()) {
for (int i = 1; i <= m.groupCount(); i++) {
String name = m.group(i);
pathVariables.add(name);
s = m.replaceFirst(NAME_REPLACEMENT.replaceAll("%NAME%", name));
m.reset(s);
}
}
m = FULL_SPLAT_PATTERN.matcher(s);
while (m.find()) {
s = m.replaceAll(FULL_SPLAT_REPLACEMENT);
m.reset(s);
}
this.uriPattern = Pattern.compile(s + "$");
}
/**
* Tests the given {@code uri} against this template, returning {@code true} if the
* uri matches the template, {@code false} otherwise.
*
* @param uri The uri to match
*
* @return {@code true} if there's a match, {@code false} otherwise
*/
public boolean matches(String uri) {
return matcher(uri).matches();
}
/**
* Matches the template against the given {@code uri} returning a map of path parameters
* extracted from the uri, keyed by the names in the template. If the uri does not match,
* or there are no path parameters, an empty map is returned.
*
* @param uri The uri to match
*
* @return the path parameters from the uri. Never {@code null}.
*/
public Map match(String uri) {
Map pathParameters = vars.get(uri);
if (null != pathParameters) {
return pathParameters;
}
pathParameters = new HashMap();
Matcher m = matcher(uri);
if (m.matches()) {
int i = 1;
for (String name : pathVariables) {
String val = m.group(i++);
pathParameters.put(name, val);
}
}
synchronized (vars) {
vars.put(uri, pathParameters);
}
return pathParameters;
}
private Matcher matcher(String uri) {
Matcher m = matchers.get(uri);
if (null == m) {
m = uriPattern.matcher(uri);
synchronized (matchers) {
matchers.put(uri, m);
}
}
return m;
}
}