reactor.bus.selector.RegexSelector 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 javax.annotation.Nullable;
import java.util.HashMap;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* A {@link Selector} implementation based on the given regular expression. Parses it into a {@link Pattern} for
* efficient matching against keys.
*
* An example of creating a regex Selector would be:
*
* Selectors.R("event([0-9]+)")
*
* This would match keys like:
*
* "event1", "event23", or "event9"
*
* @author Jon Brisbin
* @author Andy Wilkinson
*/
public class RegexSelector extends ObjectSelector {
private final HeaderResolver headerResolver = new HeaderResolver() {
@Nullable
@Override
public Map resolve(Object key) {
Matcher m = getObject().matcher(key.toString());
if(!m.matches()) {
return null;
}
int groups = m.groupCount();
Map headers = new HashMap();
for(int i = 1; i <= groups; i++) {
String name = "group" + i;
String value = m.group(i);
headers.put(name, value);
}
return headers;
}
};
/**
* Create a {@link Selector} when the given regex pattern.
*
* @param pattern
* The regex String that will be compiled into a {@link Pattern}.
*/
public RegexSelector(String pattern) {
super(Pattern.compile(pattern));
}
/**
* Creates a {@link Selector} based on the given regular expression.
*
* @param regex
* The regular expression to compile.
*
* @return The new {@link Selector}.
*/
public static Selector regexSelector(String regex) {
return new RegexSelector(regex);
}
@Override
public boolean matches(Object key) {
return key instanceof String
&& getObject().matcher((String)key).matches();
}
@Override
public HeaderResolver getHeaderResolver() {
return headerResolver;
}
}