OSGiTestUtils.java

/*
 * 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 calculator.dosgi.test;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;

import org.osgi.framework.Bundle;

/**
 *
 * Utility class to create OSGi bundles
 *
 * @version $Rev$ $Date$
 */
public class OSGiTestUtils {
    private static class InvocationHandlerImpl implements InvocationHandler {
        private Object instance;

        public InvocationHandlerImpl(Object instance) {
            super();
            this.instance = instance;
        }

        public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
            Method m = instance.getClass().getMethod(method.getName(), method.getParameterTypes());
            return m.invoke(instance, args);
        }

    }

    /**
     * Returns a string representation of the given bundle.
     *
     * @param b
     * @param verbose
     * @return
     */
    public static String bundleStatus(Bundle bundle, boolean verbose) {
        StringBuffer sb = new StringBuffer();
        sb.append(bundle.getBundleId()).append(" ").append(bundle.getSymbolicName());
        int s = bundle.getState();
        if ((s & Bundle.UNINSTALLED) != 0) {
            sb.append(" UNINSTALLED");
        }
        if ((s & Bundle.INSTALLED) != 0) {
            sb.append(" INSTALLED");
        }
        if ((s & Bundle.RESOLVED) != 0) {
            sb.append(" RESOLVED");
        }
        if ((s & Bundle.STARTING) != 0) {
            sb.append(" STARTING");
        }
        if ((s & Bundle.STOPPING) != 0) {
            sb.append(" STOPPING");
        }
        if ((s & Bundle.ACTIVE) != 0) {
            sb.append(" ACTIVE");
        }

        if (verbose) {
            sb.append(" ").append(bundle.getLocation());
            sb.append(" ").append(bundle.getHeaders());
        }
        return sb.toString();
    }

    /**
     * A utility to cast the object to the given interface. If the class for the object
     * is loaded by a different classloader, a proxy will be created.
     *
     * @param <T>
     * @param obj
     * @param cls
     * @return
     */
    public static <T> T cast(Object obj, Class<T> cls) {
        if (cls.isInstance(obj)) {
            return cls.cast(obj);
        } else {
            return cls.cast(Proxy.newProxyInstance(cls.getClassLoader(),
                                                   new Class<?>[] {cls},
                                                   new InvocationHandlerImpl(obj)));
        }
    }
}