ASF_20_SRC_AUTO/src/blocks/xmlform/java/org/apache/cocoon/acting/AbstractControllerAction.java - cocoon - Git at Google

 /*
  * Copyright 1999-2004 The Apache Software Foundation.
  *
  * 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.apache.cocoon.acting;

 import org.apache.avalon.framework.CascadingRuntimeException;
 import org.apache.avalon.framework.configuration.Configuration;
 import org.apache.avalon.framework.configuration.ConfigurationException;
 import org.apache.avalon.framework.parameters.Parameters;
 import org.apache.avalon.framework.thread.ThreadSafe;
 import org.apache.cocoon.Constants;
 import org.apache.cocoon.components.validation.Validator;
 import org.apache.cocoon.components.xmlform.Form;
 import org.apache.cocoon.environment.ObjectModelHelper;
 import org.apache.cocoon.environment.Redirector;
 import org.apache.cocoon.environment.Request;
 import org.apache.cocoon.environment.SourceResolver;

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

 /**
  * This action extends the idea of the AbstractXMLFormAction. It
  * uses a configuration file similar to Jakarta Struts, and uses
  * the concept of the MultiAction.
  *
  * Warning! This classes is an experimental one.
  *
  * @author <a href="mailto:stephan@apache.org">Stephan Michels</a>
  * @version CVS $Id: AbstractControllerAction.java,v 1.4 2004/03/05 13:02:37 bdelacretaz Exp $
  */
 public abstract class AbstractControllerAction
   extends AbstractComplementaryConfigurableAction implements ThreadSafe {

     private static final String ACTION_METHOD_PREFIX = "do";

     private HashMap methodIndex;

     private static final String removePrefix(String name) {
         int prefixLen = ACTION_METHOD_PREFIX.length();

         return name.substring(prefixLen, prefixLen+1).toLowerCase()+
                name.substring(prefixLen+1);
     }

     /**
      * Configure the action.
      */
     public void configure(Configuration conf) throws ConfigurationException {
         super.configure(conf);

         try {
             Method[] methods = this.getClass().getMethods();

             methodIndex = new HashMap();

             for (int i = 0; i<methods.length; i++) {
                 String methodName = methods[i].getName();

                 if (methodName.startsWith(ACTION_METHOD_PREFIX)) {
                     String actionName = removePrefix(methodName);

                     methodIndex.put(actionName, methods[i]);
                     if (getLogger().isDebugEnabled()) {
                         getLogger().debug("registered method \""+methodName+
                                           "\" as action \""+actionName+"\"");
                     }
                 }
             }
         } catch (Exception e) {
             throw new ConfigurationException("cannot get methods by reflection",
                                              e);
         }
     }

     /**
      * Perform the action.
      */
     public Map act(Redirector redirector, SourceResolver resolver,
                    Map objectModel, String src,
                    Parameters params) throws Exception {

         Request request = (Request) (objectModel.get(ObjectModelHelper.REQUEST_OBJECT));

         // load controller configuration
         Configuration config = getConfiguration(src, resolver, true);

         // current path
         String path = request.getSitemapURI();

         String base = request.getRequestURI().substring(0,
                           request.getRequestURI().length()-path.length());

         // ensure that there is a form available
         // through the rest of the flow
         Form form = getForm(config, path, objectModel);

         if (form==null) {
             throw new IllegalStateException("Action could not obtain the Form");
         }

         // populate form with request parameters
         // population is automatically followed by validation by default.
         // If this is not the desired behaviour, the Form class can be subclassed
         form.populate(objectModel);

         // If the currect form have incorrect values, then process the same page
         if (form.getViolations()!=null) {
             return EMPTY_MAP;
         }

         // find and save the action command
         String command = getCommand(request);

         if ((command==null) || (command.length()==0)) {
             // if no command send, process current page
             return EMPTY_MAP;
         }

         // find the action name for the method, which should be performed.
         String action = getAction(config, path);

         // perform action method
         String forward = command;

         if ((action!=null) && (action.length()>0)) {
             Method method = (Method) methodIndex.get(action);

             if (method!=null) {
                 forward = ((String) method.invoke(this, new Object[]{ command,
                                                                       form }));
                 if (forward==null) {
                     forward = command;
                 }
             }
         }
         if ((command==null) || (command.length()==0)) {
             // if no command send, process current page
             return EMPTY_MAP;
         }

         // if action returns violation, process current form
         if ((forward==null) && (form.getViolations()!=null)) {
             return EMPTY_MAP;
         }

         // process forward
         String newpath = getForward(config, path, forward);

         if (path.equals(newpath)) {
             return EMPTY_MAP;
         } else {
             redirector.redirect(true, base+newpath);
             return null;
         }
     }

     /**
      * Returns name of the action for a given page.
      */
     private String getAction(Configuration config, String path) {

         Configuration[] actions = config.getChild("action-mappings").getChildren("action");

         String action = null;

         for (int i = 0; i<actions.length; i++)
             if (actions[i].getAttribute("path", null).equals(path)) {
                 action = actions[i].getAttribute("name", null);
             }

         return (action!=null) ? action.toLowerCase() : null;
     }

     /**
      * Get the command which was submitted with the form.
      * It is extracted from the standard cocoon-action-* request parameter
      */
     private String getCommand(Request request) {
         Enumeration enum = request.getParameterNames();

         while (enum.hasMoreElements()) {
             String paramName = (String) enum.nextElement();

             // search for the command
             if (paramName.startsWith(Constants.ACTION_PARAM_PREFIX)) {
                 return paramName.substring(Constants.ACTION_PARAM_PREFIX.length(),
                                            paramName.length());
             }
         }
         return null;
     }

     /**
      * Return the page for a given forward.
      */
     private String getForward(Configuration config, String path,
                               String name) {

         Configuration[] actions = config.getChild("action-mappings").getChildren("action");

         for (int i = 0; i<actions.length; i++)
             if (actions[i].getAttribute("path", null).equals(path)) {
                 Configuration[] forwards = actions[i].getChildren("forward");

                 for (int j = 0; j<forwards.length; j++)
                     if (forwards[j].getAttribute("name", null).equals(name)) {
                         return forwards[j].getAttribute("path", null);
                     }
             }

         Configuration[] forwards = config.getChild("global-forwards").getChildren("forward");

         for (int i = 0; i<forwards.length; i++)
             if (forwards[i].getAttribute("name", null).equals(name)) {
                 return forwards[i].getAttribute("path", null);
             }

         return null;
     }

     /**
      * Invoked during the form population process
      *
      * Provides default implementation, which
      * can be extended or replaced by subclasses
      *
      * Implementations of this method are responsible
      * for creating and
      * returning the Form object which the action
      * is working on.
      *
      * @return Form the form object this action works with
      */
     private Form getForm(Configuration config, String path, Map objectModel) {
         Form form = Form.lookup(objectModel, getFormId(config, path));

         if (form!=null) {
             return form;
         } else {
             // create new form
             form = new Form(getFormId(config, path),
                             getFormModel(config, path));
             Validator v = null; // getFormValidator();

             form.setValidator(v);
             form.save(objectModel, getFormScope(config, path));
             return form;
         }
     }

     /**
      * Extract xmlform-model action parameter and
      * instantiate a new form model it.
      *
      * Subclasses may override this method
      * to use custom model instantiation technique
      *
      * @return Form model
      */
     private Object getFormModel(Configuration config, String path) {

         String formId = getFormId(config, path);

         Configuration[] beans = config.getChild("form-beans").getChildren("form-bean");

         String modelClassName = null;

         for (int i = 0; i<beans.length; i++)
             if (beans[i].getAttribute("name", null).equals(formId)) {
                 modelClassName = beans[i].getAttribute("type", null);
             }

         try {
             Class modelClass = Class.forName(modelClassName);
             Object o = modelClass.newInstance();

             return o;
         } catch (Exception e) {
             throw new CascadingRuntimeException(" Failed instantiating form model ",
                                                 e);
         }
     }

     /**
      * Returns the form id for a given page.
      */
     private String getFormId(Configuration config, String path) {
         Configuration[] actions = config.getChild("action-mappings").getChildren("action");

         String formId = null;

         for (int i = 0; i<actions.length; i++)
             if (actions[i].getAttribute("path", null).equals(path)) {
                 formId = actions[i].getAttribute("form", null);
             }

         if (formId==null) {
             throw new RuntimeException(" xmlform-id not specified ");
         } else {
             return formId;
         }
     }

     /**
      * Returns the scope of the form for a given page.
      */
     private String getFormScope(Configuration config, String path) {

         Configuration[] actions = config.getChild("action-mappings").getChildren("action");

         String formScope = null;

         for (int i = 0; i<actions.length; i++)
             if (actions[i].getAttribute("path", null).equals(path)) {
                 formScope = actions[i].getAttribute("scope", null);
             }

         if (formScope==null) {
             // default to request scope
             formScope = Form.SCOPE_REQUEST;
         }

         return formScope;
     }
 }
	/*
	* Copyright 1999-2004 The Apache Software Foundation.
	*
	* 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.apache.cocoon.acting;

	import org.apache.avalon.framework.CascadingRuntimeException;
	import org.apache.avalon.framework.configuration.Configuration;
	import org.apache.avalon.framework.configuration.ConfigurationException;
	import org.apache.avalon.framework.parameters.Parameters;
	import org.apache.avalon.framework.thread.ThreadSafe;
	import org.apache.cocoon.Constants;
	import org.apache.cocoon.components.validation.Validator;
	import org.apache.cocoon.components.xmlform.Form;
	import org.apache.cocoon.environment.ObjectModelHelper;
	import org.apache.cocoon.environment.Redirector;
	import org.apache.cocoon.environment.Request;
	import org.apache.cocoon.environment.SourceResolver;

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

	/**
	* This action extends the idea of the AbstractXMLFormAction. It
	* uses a configuration file similar to Jakarta Struts, and uses
	* the concept of the MultiAction.
	*
	* Warning! This classes is an experimental one.
	*
	* @author <a href="mailto:stephan@apache.org">Stephan Michels</a>
	* @version CVS $Id: AbstractControllerAction.java,v 1.4 2004/03/05 13:02:37 bdelacretaz Exp $
	*/
	public abstract class AbstractControllerAction
	extends AbstractComplementaryConfigurableAction implements ThreadSafe {

	private static final String ACTION_METHOD_PREFIX = "do";

	private HashMap methodIndex;

	private static final String removePrefix(String name) {
	int prefixLen = ACTION_METHOD_PREFIX.length();

	return name.substring(prefixLen, prefixLen+1).toLowerCase()+
	name.substring(prefixLen+1);
	}

	/**
	* Configure the action.
	*/
	public void configure(Configuration conf) throws ConfigurationException {
	super.configure(conf);

	try {
	Method[] methods = this.getClass().getMethods();

	methodIndex = new HashMap();

	for (int i = 0; i<methods.length; i++) {
	String methodName = methods[i].getName();

	if (methodName.startsWith(ACTION_METHOD_PREFIX)) {
	String actionName = removePrefix(methodName);

	methodIndex.put(actionName, methods[i]);
	if (getLogger().isDebugEnabled()) {
	getLogger().debug("registered method \""+methodName+
	"\" as action \""+actionName+"\"");
	}
	}
	}
	} catch (Exception e) {
	throw new ConfigurationException("cannot get methods by reflection",
	e);
	}
	}

	/**
	* Perform the action.
	*/
	public Map act(Redirector redirector, SourceResolver resolver,
	Map objectModel, String src,
	Parameters params) throws Exception {

	Request request = (Request) (objectModel.get(ObjectModelHelper.REQUEST_OBJECT));

	// load controller configuration
	Configuration config = getConfiguration(src, resolver, true);

	// current path
	String path = request.getSitemapURI();

	String base = request.getRequestURI().substring(0,
	request.getRequestURI().length()-path.length());

	// ensure that there is a form available
	// through the rest of the flow
	Form form = getForm(config, path, objectModel);

	if (form==null) {
	throw new IllegalStateException("Action could not obtain the Form");
	}

	// populate form with request parameters
	// population is automatically followed by validation by default.
	// If this is not the desired behaviour, the Form class can be subclassed
	form.populate(objectModel);

	// If the currect form have incorrect values, then process the same page
	if (form.getViolations()!=null) {
	return EMPTY_MAP;
	}

	// find and save the action command
	String command = getCommand(request);

	if ((command==null) \|\| (command.length()==0)) {
	// if no command send, process current page
	return EMPTY_MAP;
	}

	// find the action name for the method, which should be performed.
	String action = getAction(config, path);

	// perform action method
	String forward = command;

	if ((action!=null) && (action.length()>0)) {
	Method method = (Method) methodIndex.get(action);

	if (method!=null) {
	forward = ((String) method.invoke(this, new Object[]{ command,
	form }));
	if (forward==null) {
	forward = command;
	}
	}
	}
	if ((command==null) \|\| (command.length()==0)) {
	// if no command send, process current page
	return EMPTY_MAP;
	}

	// if action returns violation, process current form
	if ((forward==null) && (form.getViolations()!=null)) {
	return EMPTY_MAP;
	}

	// process forward
	String newpath = getForward(config, path, forward);

	if (path.equals(newpath)) {
	return EMPTY_MAP;
	} else {
	redirector.redirect(true, base+newpath);
	return null;
	}
	}

	/**
	* Returns name of the action for a given page.
	*/
	private String getAction(Configuration config, String path) {

	Configuration[] actions = config.getChild("action-mappings").getChildren("action");

	String action = null;

	for (int i = 0; i<actions.length; i++)
	if (actions[i].getAttribute("path", null).equals(path)) {
	action = actions[i].getAttribute("name", null);
	}

	return (action!=null) ? action.toLowerCase() : null;
	}

	/**
	* Get the command which was submitted with the form.
	* It is extracted from the standard cocoon-action-* request parameter
	*/
	private String getCommand(Request request) {
	Enumeration enum = request.getParameterNames();

	while (enum.hasMoreElements()) {
	String paramName = (String) enum.nextElement();

	// search for the command
	if (paramName.startsWith(Constants.ACTION_PARAM_PREFIX)) {
	return paramName.substring(Constants.ACTION_PARAM_PREFIX.length(),
	paramName.length());
	}
	}
	return null;
	}

	/**
	* Return the page for a given forward.
	*/
	private String getForward(Configuration config, String path,
	String name) {

	Configuration[] actions = config.getChild("action-mappings").getChildren("action");

	for (int i = 0; i<actions.length; i++)
	if (actions[i].getAttribute("path", null).equals(path)) {
	Configuration[] forwards = actions[i].getChildren("forward");

	for (int j = 0; j<forwards.length; j++)
	if (forwards[j].getAttribute("name", null).equals(name)) {
	return forwards[j].getAttribute("path", null);
	}
	}

	Configuration[] forwards = config.getChild("global-forwards").getChildren("forward");

	for (int i = 0; i<forwards.length; i++)
	if (forwards[i].getAttribute("name", null).equals(name)) {
	return forwards[i].getAttribute("path", null);
	}

	return null;
	}

	/**
	* Invoked during the form population process
	*
	* Provides default implementation, which
	* can be extended or replaced by subclasses
	*
	* Implementations of this method are responsible
	* for creating and
	* returning the Form object which the action
	* is working on.
	*
	* @return Form the form object this action works with
	*/
	private Form getForm(Configuration config, String path, Map objectModel) {
	Form form = Form.lookup(objectModel, getFormId(config, path));

	if (form!=null) {
	return form;
	} else {
	// create new form
	form = new Form(getFormId(config, path),
	getFormModel(config, path));
	Validator v = null; // getFormValidator();

	form.setValidator(v);
	form.save(objectModel, getFormScope(config, path));
	return form;
	}
	}

	/**
	* Extract xmlform-model action parameter and
	* instantiate a new form model it.
	*
	* Subclasses may override this method
	* to use custom model instantiation technique
	*
	* @return Form model
	*/
	private Object getFormModel(Configuration config, String path) {

	String formId = getFormId(config, path);

	Configuration[] beans = config.getChild("form-beans").getChildren("form-bean");

	String modelClassName = null;

	for (int i = 0; i<beans.length; i++)
	if (beans[i].getAttribute("name", null).equals(formId)) {
	modelClassName = beans[i].getAttribute("type", null);
	}

	try {
	Class modelClass = Class.forName(modelClassName);
	Object o = modelClass.newInstance();

	return o;
	} catch (Exception e) {
	throw new CascadingRuntimeException(" Failed instantiating form model ",
	e);
	}
	}

	/**
	* Returns the form id for a given page.
	*/
	private String getFormId(Configuration config, String path) {
	Configuration[] actions = config.getChild("action-mappings").getChildren("action");

	String formId = null;

	for (int i = 0; i<actions.length; i++)
	if (actions[i].getAttribute("path", null).equals(path)) {
	formId = actions[i].getAttribute("form", null);
	}

	if (formId==null) {
	throw new RuntimeException(" xmlform-id not specified ");
	} else {
	return formId;
	}
	}

	/**
	* Returns the scope of the form for a given page.
	*/
	private String getFormScope(Configuration config, String path) {

	Configuration[] actions = config.getChild("action-mappings").getChildren("action");

	String formScope = null;

	for (int i = 0; i<actions.length; i++)
	if (actions[i].getAttribute("path", null).equals(path)) {
	formScope = actions[i].getAttribute("scope", null);
	}

	if (formScope==null) {
	// default to request scope
	formScope = Form.SCOPE_REQUEST;
	}

	return formScope;
	}
	}