com.sos.scheduler.engine.kernel.command.DispatchingCommandExecutor.java Source code

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Here is the source code for com.sos.scheduler.engine.kernel.command.DispatchingCommandExecutor.java

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/**
 * Copyright (C) 2014 BigLoupe http://bigloupe.github.io/SoS-JobScheduler/
 *
 * 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
 */
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** Copyright (C) 2003-2012 Software- und Organisations-Service GmbH. 
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package com.sos.scheduler.engine.kernel.command;

import com.google.common.collect.ImmutableMap;

class DispatchingCommandExecutor implements CommandExecutor {
    private final ImmutableMap<Class<?>, CommandExecutor> commandExecutors;

    DispatchingCommandExecutor(Iterable<CommandExecutor> executors) {
        commandExecutors = mapOfExecutors(executors);
    }

    private static ImmutableMap<Class<?>, CommandExecutor> mapOfExecutors(Iterable<CommandExecutor> executors) {
        ImmutableMap.Builder<Class<?>, CommandExecutor> b = new ImmutableMap.Builder<Class<?>, CommandExecutor>();
        for (CommandExecutor ex : executors)
            b.put(ex.getCommandClass(), ex);
        return b.build();
    }

    @Override
    public final Class<? extends Command> getCommandClass() {
        return Command.class; // Dummy
    }

    @Override
    public final Result execute(Command c) {
        CommandExecutor e = commandExecutor(c.getClass());
        return e.execute(c);
    }

    private CommandExecutor commandExecutor(Class<?> commandClass) {
        CommandExecutor result = commandExecutors.get(commandClass);
        if (result == null)
            throw new UnknownCommandException(commandClass.getName());
        return result;
    }
}