Java tutorial
/** * * 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.felix.karaf.deployer.blueprint; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.net.MalformedURLException; import java.net.URL; import java.net.URLConnection; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.osgi.service.url.AbstractURLStreamHandlerService; /** * A URL handler that will transform a JBI artifact to an OSGi bundle * on the fly. Needs to be registered in the OSGi registry. */ public class BlueprintURLHandler extends AbstractURLStreamHandlerService { private static Log logger = LogFactory.getLog(BlueprintURLHandler.class); private static String SYNTAX = "blueprint: bp-xml-uri"; private URL blueprintXmlURL; /** * Open the connection for the given URL. * * @param url the url from which to open a connection. * @return a connection on the specified URL. * @throws IOException if an error occurs or if the URL is malformed. */ @Override public URLConnection openConnection(URL url) throws IOException { if (url.getPath() == null || url.getPath().trim().length() == 0) { throw new MalformedURLException("Path can not be null or empty. Syntax: " + SYNTAX); } blueprintXmlURL = new URL(url.getPath()); logger.debug("Blueprint xml URL is: [" + blueprintXmlURL + "]"); return new Connection(url); } public URL getBlueprintXmlURL() { return blueprintXmlURL; } public class Connection extends URLConnection { public Connection(URL url) { super(url); } @Override public void connect() throws IOException { } @Override public InputStream getInputStream() throws IOException { try { ByteArrayOutputStream os = new ByteArrayOutputStream(); BlueprintTransformer.transform(blueprintXmlURL, os); os.close(); return new ByteArrayInputStream(os.toByteArray()); } catch (Exception e) { logger.error("Error opening blueprint xml url", e); throw (IOException) new IOException("Error opening blueprint xml url").initCause(e); } } } }