org.getobjects.appserver.core.WODirectAction.java Source code

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Here is the source code for org.getobjects.appserver.core.WODirectAction.java

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/*
  Copyright (C) 2006-2007 Helge Hess
    
  This file is part of Go.
    
  Go is free software; you can redistribute it and/or modify it under
  the terms of the GNU Lesser General Public License as published by the
  Free Software Foundation; either version 2, or (at your option) any
  later version.
    
  Go 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 Lesser General Public
  License for more details.
    
  You should have received a copy of the GNU Lesser General Public
  License along with Go; see the file COPYING.  If not, write to the
  Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  02111-1307, USA.
*/

package org.getobjects.appserver.core;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Collection;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.getobjects.foundation.NSJavaRuntime;

/**
 * A WODirectAction object is pretty much like a servlet, it can accept
 * requests and is responsible for producing a result. The result can be
 * either a WOResponse or a WOComponent or anything else which can be
 * rendered by Go.
 * 
 * @author helge
 */
public class WODirectAction extends WOAction {
    protected static final Log daLog = LogFactory.getLog("WODirectAction");

    static Class[] emptyClassArray = new Class[0];
    static Object[] emptyObjectArray = new Object[0];

    public WODirectAction(WOContext _ctx) {
        super(_ctx);
    }

    /**
     * Just calls the matching static method which contains the actual
     * implementation. Subclasses can override the instance method to
     * implement a custom behaviour (eg clean up the name prior passing it
     * to the super implementation).
     * 
     * @param _name - the name of the action to invoke
     * @return the result, eg a WOComponent or WOResponse
     */
    public Object performActionNamed(String _name) {
        return WODirectAction.performActionNamed(this, _name, this.context());
    }

    /**
     * Implements the "direct action" request handling / method lookup. This is
     * a static method because its reused by WOComponent.
     * <p>
     * This implementation checks for a method with a name which ends in "Action"
     * and which has no parameters, eg:<pre>
     *   defaultAction
     *   viewAction</pre>
     * Hence only methods ending in "Action" are exposed (automagically) to the
     * web.
     * 
     * @param _o    - the WODirectAction or WOComponent
     * @param _name - the name of the action to invoke
     * @param _ctx  - the WOContext to run the action in
     * @return the result, eg a WOComponent or WOResponse
     */
    public static Object performActionNamed(Object _o, String _name, WOContext _ctx) {
        if (_o == null || _name == null)
            return null;

        Method m = NSJavaRuntime.NSMethodFromString(_o.getClass(), _name + "Action", emptyClassArray);

        if (m == null) {
            /* Hm, warn can be turned off since handleMissingAction could perform
             * a sensible implementation. Or should handleMissingAction() do the
             * log?
             */
            daLog.warn("did not find method for DA: " + _name + " (object=" + _o + ")");
            return _ctx.application().handleMissingAction(_name, _ctx);
        }

        Object results;
        try {
            results = m.invoke(_o, emptyObjectArray);
        } catch (InvocationTargetException ite) {
            results = _ctx.application().handleException(ite.getCause(), _ctx);
        } catch (IllegalAccessException iae) {
            // TODO: improve logging
            daLog.error("invalid access for DA, must be public: " + iae);
            results = _ctx.application().handleMissingAction(_name, _ctx);
        }
        return results;
    }

    /**
     * This method gets triggered if the direct action URL contained no action
     * name. The default implementation returns the Main component.
     * 
     * @return the result of the action
     */
    public Object defaultAction() {
        return this.pageWithName("Main");
    }

    /* form values */

    /**
     * Iterates over the given keys and invokes takeValueForKey for each key,
     * using a similiar named form values as the value.
     */
    public void takeFormValueArraysForKeyArray(String[] _keys) {
        WORequest r = this.request();

        for (String k : _keys)
            this.takeValueForKey(r.formValuesForKey(k), k);
    }

    public void takeFormValueArraysForKeyArray(Collection<String> _keys) {
        this.takeFormValueArraysForKeyArray((String[]) _keys.toArray());
    }
}