BatchActionHandler.java

/*
 * Copyright 2011 ArcBees Inc.
 *
 * 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.
 */

package com.gwtplatform.dispatch.rpc.server.actionhandler;

import java.util.List;

import com.gwtplatform.dispatch.rpc.server.ExecutionContext;
import com.gwtplatform.dispatch.rpc.shared.Action;
import com.gwtplatform.dispatch.rpc.shared.BatchAction;
import com.gwtplatform.dispatch.rpc.shared.BatchAction.OnException;
import com.gwtplatform.dispatch.rpc.shared.BatchResult;
import com.gwtplatform.dispatch.rpc.shared.Result;
import com.gwtplatform.dispatch.shared.ActionException;

/**
 * This handles {@link BatchAction} requests, which are a set of multiple actions that need to all be executed
 * successfully in sequence for the whole action to succeed.
 */
public class BatchActionHandler extends AbstractActionHandler<BatchAction, BatchResult> {
    public BatchActionHandler() {
        super(BatchAction.class);
    }

    public BatchResult execute(BatchAction action, ExecutionContext context)
            throws ActionException {
        OnException onException = action.getOnException();
        List<Result> results = new java.util.ArrayList<>();
        for (Action<?> a : action.getActions()) {
            Result result = null;
            try {
                result = context.execute(a);
            } catch (Exception e) {
                if (onException == OnException.ROLLBACK) {
                    if (e instanceof ActionException) {
                        throw (ActionException) e;
                    }
                    if (e instanceof RuntimeException) {
                        throw (RuntimeException) e;
                    } else {
                        throw new ActionException(e);
                    }
                }
            }
            results.add(result);
        }

        return new BatchResult(results);
    }

    public void undo(BatchAction action, BatchResult result,
                     ExecutionContext context) throws ActionException {
        // No action necessary - the sub actions should automatically rollback
    }
}