001/*
002 * (C) Copyright 2006-2011 Nuxeo SA (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     bstefanescu
018 */
019package org.nuxeo.ecm.webengine.jaxrs;
020
021import java.io.IOException;
022import java.util.HashMap;
023import java.util.Map;
024import java.util.Set;
025
026import javax.ws.rs.core.Application;
027
028import org.osgi.framework.Bundle;
029
030/**
031 * A wrapper for a JAX-RS application fragment declared in manifest. The fragment application will be added to the
032 * target host application.
033 *
034 * @author <a href="mailto:bs@nuxeo.com">Bogdan Stefanescu</a>
035 */
036public class ApplicationFragment extends Application {
037
038    protected final String hostName;
039
040    protected final Bundle bundle;
041
042    protected final Map<String, String> attrs;
043
044    protected String appClass;
045
046    private volatile Application app;
047
048    public static Map<String, String> createAttributes(String hostName) {
049        HashMap<String, String> attrs = new HashMap<String, String>();
050        if (hostName != null) {
051            attrs.put("host", hostName);
052        }
053        return attrs;
054    }
055
056    public ApplicationFragment(Bundle bundle, String appClass) {
057        this(bundle, appClass, (String) null);
058    }
059
060    public ApplicationFragment(Bundle bundle, String appClass, String host) {
061        this(bundle, appClass, createAttributes(host));
062    }
063
064    public ApplicationFragment(Bundle bundle, String appClass, Map<String, String> attrs) {
065        this.bundle = bundle;
066        this.appClass = appClass;
067        this.attrs = attrs;
068        String host = attrs.get("host");
069        this.hostName = host == null ? "default" : host;
070    }
071
072    protected synchronized void createApp() {
073        try {
074            Object obj = bundle.loadClass(appClass).newInstance();
075            if (obj instanceof ApplicationFactory) {
076                app = ((ApplicationFactory) obj).getApplication(bundle, attrs);
077            } else if (obj instanceof Application) {
078                app = (Application) obj;
079            } else {
080                throw new IllegalArgumentException("Expecting an Application or ApplicationFactory class: " + appClass);
081            }
082        } catch (ReflectiveOperationException | IOException e) {
083            String msg = "Cannot instantiate JAX-RS application " + appClass + " from bundle "
084                    + bundle.getSymbolicName();
085            throw new RuntimeException(msg, e);
086        }
087    }
088
089    public synchronized void reload() {
090        app = null;
091    }
092
093    public Bundle getBundle() {
094        return bundle;
095    }
096
097    public Map<String, String> getAttrs() {
098        return attrs;
099    }
100
101    public String getHostName() {
102        return hostName;
103    }
104
105    public Application get() {
106        if (app == null) {
107            createApp();
108        }
109        return app;
110    }
111
112    @Override
113    public Set<Class<?>> getClasses() {
114        return get().getClasses();
115    }
116
117    @Override
118    public Set<Object> getSingletons() {
119        return get().getSingletons();
120    }
121
122}