org.colombbus.tangara.commons.resinject.ActionResourceImpl.java Source code

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Here is the source code for org.colombbus.tangara.commons.resinject.ActionResourceImpl.java

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/**
 * Tangara is an educational platform to get started with programming. Copyright
 * (C) 2010 Colombbus (http://www.colombbus.org)
 * 
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */
package org.colombbus.tangara.commons.resinject;

import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Map;

import javax.swing.AbstractButton;
import javax.swing.Action;

import org.apache.commons.lang3.Validate;
import org.colombbus.tangara.commons.mvc.Command;
import org.colombbus.tangara.commons.mvc.CommandFactory;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Default action store implementation
 * <p>
 * Usage:
 * 
 * <pre>
 * ActionResourceImpl actionStore = new ActionResource();
 * actionStore.setClassResource(...);
 * actionStore.setActionHolder(...);
 * actionStore.initialize();
 * ...
 * Action action = actionStore.getAction("aCommand");
 * </pre>
 * 
 * </p>
 * 
 * @author gwen
 */
public class ActionResourceImpl implements ActionResource {

    private final Logger LOG = LoggerFactory.getLogger(ActionResourceImpl.class);
    private final Map<Command, Action> commandActionMap = new HashMap<Command, Action>();
    private ClassResource classResource;
    private Object actionHolder;

    public ActionResourceImpl() {
    }

    public void setClassResource(ClassResource classResource) {
        Validate.notNull(classResource, "classResource argument is null"); //$NON-NLS-1$
        this.classResource = classResource;
    }

    public void setActionHolder(Object actionHolder) {
        Validate.notNull(actionHolder, "actionHolder argument is null"); //$NON-NLS-1$
        this.actionHolder = actionHolder;
    }

    public void initialize() {
        checkAttributeSet(classResource, "classResource not set"); //$NON-NLS-1$
        checkAttributeSet(actionHolder, "actionHolder not set"); //$NON-NLS-1$

        for (Method method : actionHolder.getClass().getDeclaredMethods()) {
            if (method.isAnnotationPresent(ActionPerformer.class))
                parseMethod(method);
        }
    }

    private void checkAttributeSet(Object attribute, String message) {
        if (attribute == null) {
            LOG.error(message);
            throw new RuntimeException(message);
        }
    }

    private void parseMethod(Method method) {
        ActionPerformer actionPerformer = method.getAnnotation(ActionPerformer.class);

        String commandId = actionPerformer.command();
        if (commandId.length() == 0)
            commandId = method.getName();
        Command command = CommandFactory.getCommand(commandId);

        String resourceKey = actionPerformer.resource();
        if (resourceKey.length() == 0)
            resourceKey = method.getName();

        MessageSenderAction action = new MessageSenderAction();
        action.setTarget(actionHolder);
        action.setMessage(method.getName());

        injectAction(action, resourceKey);

        commandActionMap.put(command, action);
    }

    private void injectAction(Action action, String actionKey) {
        ActionInjecter injecter = new ActionInjecter();

        injecter.setClassResource(classResource);
        injecter.setAction(action);
        injecter.setActionKey(actionKey);

        injecter.inject();
    }

    @Override
    public Action getAction(Command command) {
        checkCommandExist(command);
        Action action = commandActionMap.get(command);
        return action;
    }

    private void checkCommandExist(Command command) {
        Validate.notNull(command, "command argument is null"); //$NON-NLS-1$
        if (commandActionMap.containsKey(command) == false) {
            String format = "Cannot find action method for command '%s'"; //$NON-NLS-1$
            String message = String.format(format, command);
            LOG.error(message);
            throw new IllegalArgumentException(message);
        }
    }

    @Override
    public void injectAction(AbstractButton button, Command command) {
        checkCommandExist(command);
        Validate.notNull(button, "button argument is null"); //$NON-NLS-1$
        Action action = getAction(command);
        button.setAction(action);
    }

}