Groovy example source code file (SourceExtensionHandler.java)

This example Groovy source code file (SourceExtensionHandler.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Groovy tags/keywords

bufferedreader, bufferedreader, enumeration, exception, exception, groovyruntimeexception, io, ioexception, linkedhashset, net, network, set, set, sourceextensionhandler, sourceextensionhandler, string, url, util

The Groovy SourceExtensionHandler.java source code

/*
 * Copyright 2003-2007 the original author or authors.
 *
 * 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 org.codehaus.groovy.control;

import groovy.lang.GroovyRuntimeException;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;
import java.util.Enumeration;
import java.util.LinkedHashSet;
import java.util.Set;

/**
 * Looks for source file extensions in META-INF/services/org.codehaus.groovy.source.Extensions
 */

public class SourceExtensionHandler {

	public static Set<String> getRegisteredExtensions(ClassLoader loader) {
        Set<String> extensions = new LinkedHashSet();
        extensions.add("groovy");
        URL service = null;
        try {
            Enumeration<URL> globalServices = loader.getResources("META-INF/services/org.codehaus.groovy.source.Extensions");
            while (globalServices.hasMoreElements()) {
                service = globalServices.nextElement();
                String extension;
                BufferedReader svcIn = new BufferedReader(new InputStreamReader(service.openStream()));

                extension = svcIn.readLine();
                while (extension != null) {
                	extension = extension.trim();
                    if (!extension.startsWith("#") && extension.length() > 0) {
                    	extensions.add(extension);
                    }
                    extension = svcIn.readLine();
                }
            }
        } catch (IOException ex) {
        	throw new GroovyRuntimeException("IO Exception attempting to load source extension registerers. Exception: " + 
        			ex.toString() + (service == null ? "" : service.toExternalForm()));
        }
        return extensions;
	}
}