ThreadLocalIpcCallScope.java

/**
 * Copyright 2010 CosmoCode GmbH
 *
 * 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.
 */

/**
s * palava - a java-php-bridge
 * Copyright (C) 2007-2010  CosmoCode GmbH
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

package de.cosmocode.palava.ipc;

import com.google.common.base.Preconditions;
import com.google.inject.Scope;

import de.cosmocode.palava.scope.AbstractScope;

/**
 * Custom {@link Scope} implementation for one single {@link IpcCall call}.
 *
 * @author Willi Schoenborn
 * @author Tobias Sarnowski
 */
final class ThreadLocalIpcCallScope extends AbstractScope implements IpcCallScope {

    private final ThreadLocal<IpcCall> currentCall = new ThreadLocal<IpcCall>();
    
    @Override
    public void enter(IpcCall call) {
        Preconditions.checkNotNull(call, "Call");
        currentCall.set(call);
    }
    
    @Override
    public boolean isActive() {
        return currentCall.get() != null;
    }

    @Override
    public IpcCall get() {
        return currentCall.get();
    }

    @Override
    public void exit() {
        final IpcCall call = currentCall.get();
        Preconditions.checkState(call != null, "There is no %s block in progress", this);
        try {
            destroy(call);
        } finally {
            call.clear();
            currentCall.remove();
        }
    }


}