TaskClientAccessor.java

/*
 * Copyright 2012 JBoss 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 org.overlord.dtgov.ui.server.services.tasks;

import java.lang.reflect.Constructor;
import java.util.Locale;

import javax.inject.Inject;
import javax.inject.Singleton;

import org.apache.commons.configuration.Configuration;
import org.overlord.dtgov.ui.server.DtgovUIConfig;
import org.overlord.dtgov.ui.server.i18n.Messages;

/**
 * The class used whenever a request to a task server needs to be made.
 *
 * @author eric.wittmann@redhat.com
 */
@Singleton
public class TaskClientAccessor {

    private transient static ThreadLocal<ITaskClient> client = new ThreadLocal<ITaskClient>();
    private transient static ThreadLocal<Locale> tlocale = new ThreadLocal<Locale>();
    public static void setLocale(Locale locale) {
        tlocale.set(locale);
    }
    public static void clearLocale() {
        tlocale.set(null);
    }

    @Inject
    protected DtgovUIConfig config;

    /**
     * Constructor.
     * @param config
     */
    @Inject
    public TaskClientAccessor(DtgovUIConfig config) {
    }

    /**
     * Creates an instance of the task client.
     */
    public ITaskClient createClient() {
        String clientClassname = config.getConfiguration().getString(DtgovUIConfig.TASK_CLIENT_CLASS);
        if (clientClassname != null) {
            try {
                Class<?> clientClass = Class.forName(clientClassname);
                Constructor<?> constructor = null;
                try {
                    constructor = clientClass.getConstructor(Configuration.class);
                    return (ITaskClient) constructor.newInstance(config.getConfiguration());
                } catch (NoSuchMethodException e) {}
                try {
                    constructor = clientClass.getConstructor();
                    return (ITaskClient) constructor.newInstance();
                } catch (NoSuchMethodException e) {}
            } catch (Exception e) {
                throw new RuntimeException(Messages.i18n.format("TaskClientAccessor.ErrorCreatingClient"), e); //$NON-NLS-1$
            }
        }
        throw new RuntimeException(Messages.i18n.format("TaskClientAccessor.FailedTocreateClientFrom", clientClassname)); //$NON-NLS-1$
    }

    /**
     * @return the atom api client
     */
    public ITaskClient getClient() {
        if (client.get() == null) {
            client.set(createClient());
        }
        client.get().setLocale(tlocale.get());
        return client.get();
    }

}