/*
* 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.jackrabbit.rmi.client;
import java.rmi.RemoteException;
import javax.jcr.Credentials;
import javax.jcr.Repository;
import javax.jcr.RepositoryException;
import javax.jcr.Session;
import javax.jcr.Value;
import org.apache.jackrabbit.rmi.remote.RemoteRepository;
import org.apache.jackrabbit.rmi.remote.RemoteSession;
/**
* A "safe" local adapter for the JCR-RMI
* {@link org.apache.jackrabbit.rmi.remote.RemoteRepository RemoteRepository}
* interface. This class uses an abstract factory method for loading
* (and reloading) the remote repository instance that is made locally
* available through the JCR {@link Repository} interface. If the remote
* reference breaks (a RemoteException is thrown by a remote call), then
* this adapter attempts to reload the remote reference once before failing.
*
* @see javax.jcr.Repository
* @see org.apache.jackrabbit.rmi.remote.RemoteRepository
*/
public abstract class SafeClientRepository extends ClientObject
implements Repository {
/** The adapted remote repository. */
private RemoteRepository remote;
/**
* Creates a client adapter for the given remote repository.
*
* @param factory local adapter factory
*/
public SafeClientRepository(LocalAdapterFactory factory) {
super(factory);
try {
remote = getRemoteRepository(true);
} catch (RemoteException e) {
remote = new BrokenRemoteRepository(e);
}
}
/**
* Abstract factory class for getting the remote repository.
*
* @return remote repository
* @throws RemoteException if the remote repository could not be accessed
*/
protected abstract RemoteRepository getRemoteRepository()
throws RemoteException;
/**
* Method to obtain the remote remote repository.
* If initialize is true and a RepositoryException will be thrown no {@link BrokenRemoteRepository}
* will be created.
*
* @return remote repository
* @throws RemoteException if the remote repository could not be accessed
*/
protected RemoteRepository getRemoteRepository(boolean initialize)
throws RemoteException {
if (initialize) {
try {
return getRemoteRepository();
} catch (RemoteException e) {
throw new RemoteRuntimeException(e);
}
} else {
return getRemoteRepository();
}
}
/** {@inheritDoc} */
public synchronized String getDescriptor(String name) {
try {
return remote.getDescriptor(name);
} catch (RemoteException e1) {
try {
remote = getRemoteRepository(false);
return remote.getDescriptor(name);
} catch (RemoteException e2) {
remote = new BrokenRemoteRepository(e2);
throw new RemoteRuntimeException(e2);
}
}
}
/** {@inheritDoc} */
public synchronized String[] getDescriptorKeys() {
try {
return remote.getDescriptorKeys();
} catch (RemoteException e1) {
try {
remote = getRemoteRepository(false);
return remote.getDescriptorKeys();
} catch (RemoteException e2) {
remote = new BrokenRemoteRepository(e2);
throw new RemoteRuntimeException(e2);
}
}
}
private synchronized RemoteSession remoteLogin(
Credentials credentials, String workspace)
throws RepositoryException {
try {
return remote.login(credentials, workspace);
} catch (RemoteException e1) {
try {
remote = getRemoteRepository(false);
return remote.login(credentials, workspace);
} catch (RemoteException e2) {
remote = new BrokenRemoteRepository(e2);
throw new RemoteRepositoryException(e2);
}
}
}
/** {@inheritDoc} */
public Session login(Credentials credentials, String workspace)
throws RepositoryException {
RemoteSession session = remoteLogin(credentials, workspace);
return getFactory().getSession(this, session);
}
/** {@inheritDoc} */
public Session login(String workspace) throws RepositoryException {
return login(null, workspace);
}
/** {@inheritDoc} */
public Session login(Credentials credentials) throws RepositoryException {
return login(credentials, null);
}
/** {@inheritDoc} */
public Session login() throws RepositoryException {
return login(null, null);
}
/** {@inheritDoc} */
public synchronized Value getDescriptorValue(String key) {
try {
return remote.getDescriptorValue(key);
} catch (RemoteException e1) {
try {
remote = getRemoteRepository(false);
return remote.getDescriptorValue(key);
} catch (RemoteException e2) {
remote = new BrokenRemoteRepository(e2);
throw new RemoteRuntimeException(e2);
}
}
}
/** {@inheritDoc} */
public synchronized Value[] getDescriptorValues(String key) {
try {
return remote.getDescriptorValues(key);
} catch (RemoteException e1) {
try {
remote = getRemoteRepository(false);
return remote.getDescriptorValues(key);
} catch (RemoteException e2) {
remote = new BrokenRemoteRepository(e2);
throw new RemoteRuntimeException(e2);
}
}
}
/** {@inheritDoc} */
public synchronized boolean isSingleValueDescriptor(String key) {
try {
return remote.isSingleValueDescriptor(key);
} catch (RemoteException e1) {
try {
remote = getRemoteRepository(false);
return remote.isSingleValueDescriptor(key);
} catch (RemoteException e2) {
remote = new BrokenRemoteRepository(e2);
throw new RemoteRuntimeException(e2);
}
}
}
/** {@inheritDoc} */
public synchronized boolean isStandardDescriptor(String key) {
try {
return remote.isStandardDescriptor(key);
} catch (RemoteException e1) {
try {
remote = getRemoteRepository(false);
return remote.isStandardDescriptor(key);
} catch (RemoteException e2) {
remote = new BrokenRemoteRepository(e2);
throw new RemoteRuntimeException(e2);
}
}
}
}