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Posted to commits@click.apache.org by sa...@apache.org on 2010/10/17 06:11:27 UTC
svn commit: r1023422 - in /click/trunk/click/framework/src/org/apache/click:
Stateful.java util/ClickUtils.java
Author: sabob
Date: Sun Oct 17 04:11:26 2010
New Revision: 1023422
URL: http://svn.apache.org/viewvc?rev=1023422&view=rev
Log:
added Stateful interface and helper methods. CLK-715
Added:
click/trunk/click/framework/src/org/apache/click/Stateful.java
Modified:
click/trunk/click/framework/src/org/apache/click/util/ClickUtils.java
Added: click/trunk/click/framework/src/org/apache/click/Stateful.java
URL: http://svn.apache.org/viewvc/click/trunk/click/framework/src/org/apache/click/Stateful.java?rev=1023422&view=auto
==============================================================================
--- click/trunk/click/framework/src/org/apache/click/Stateful.java (added)
+++ click/trunk/click/framework/src/org/apache/click/Stateful.java Sun Oct 17 04:11:26 2010
@@ -0,0 +1,142 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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.click;
+
+/**
+ * Provides an interface that controls can implement that need to preserve
+ * state across multiple requests.
+ * <p/>
+ * <b>Please note:</b> Control state is not saved and restored automatically by
+ * Click. Instead, state saving and restoring is under full control of the
+ * developer through a public API.
+ * <p/>
+ * Controls implementing this interface are expected to {@link #getState() save}
+ * and {@link #setState(java.lang.Object) restore} their internal state, as well
+ * as the state of their child controls. Controls can further expose a public
+ * API for saving and restoring their state.
+ * <p/>
+ * An example implementation is shown below:
+ *
+ * <pre class="prettyprint">
+ * public class MyControl extends AbstractControl implements Stateful {
+ *
+ * private String value;
+ *
+ * ...
+ *
+ * // Return the Control internal state
+ * public Object getState() {
+ * return getValue();
+ * }
+ *
+ * // Set the Control internal state
+ * public void setState(Object state) {
+ * String fieldState = (String) state;
+ * setValue(fieldState);
+ * }
+ *
+ * // A save state helper method
+ * public void saveState(Context context) {
+ * // Save the control state in the session
+ * ClickUtils.saveState(this, getName(), context);
+ * }
+ * // A restore state helper method
+ * public void restoreState(Context context) {
+ * // Load the control state from the session
+ ClickUtils.restoreState(this, getName(), context);
+ * }
+ *
+ * // A remove state helper method
+ * public void removeState(Context context) {
+ * // Remove the control state from the session
+* ClickUtils.removeState(this, getName(), context);
+ * }
+ *
+ * } </pre>
+ *
+ * Saving and restoring Control state is controlled by the developer.
+ * <p/>
+ * For example:
+ *
+ * <pre class="prettyprint">
+ * public class MyPage extends Page {
+ *
+ * private MyControl control = new MyControl("mycontrol");
+ *
+ * public MyPage() {
+ * // Load the control state from the session
+ * control.loadState(getContext());
+ * }
+ *
+ * public void onPost() {
+ *
+ * Context context = getContext();
+ *
+ * String id = context.getParameter("id");
+ * control.setValue(id);
+ *
+ * // Save control state to the session
+ * control.saveState(context);
+ * }
+ * }
+ * </pre>
+ */
+public interface Stateful {
+
+ /**
+ * Return the Control internal state. State will generally be stored in the
+ * Session, so it is recommended to ensure the state is
+ * {@link java.io.Serializable serializable}.
+ * <p/>
+ * Example implementation below:
+ * <pre class="prettyprint">
+ * public Object getState() {
+ * Object stateArray[] = new Object[3];
+ * stateArray[0] = getValue();
+ * stateArray[1] = Number.valueOf(getNumber());
+ * stateArray[2] = Boolean.valueOf(getBoolean());
+ * return stateArray;
+ * } </pre>
+ *
+ * @return the control internal state
+ */
+ public Object getState();
+
+ /**
+ * Restore the Control internal state from the given state object.
+ * <p/>
+ * Example below:
+ * <pre class="prettyprint">
+ * public void setState(Object state) {
+ *
+ * Object[] stateArray = (Object[]) state;
+ * String storedValue = stateArray[0];
+ * setValue(storedValue);
+ *
+ * int storedNumber = ((Integer) stateArray[1]).intValue();
+ * setNumber(storedNumber);
+ *
+ * boolean storedBoolen = ((Boolean) stateArray[2]).booleanValue();
+ * setBoolean(storedBoolean);
+ * } </pre>
+ *
+ * @param state the control state to restore
+ */
+ public void setState(Object state);
+}
Modified: click/trunk/click/framework/src/org/apache/click/util/ClickUtils.java
URL: http://svn.apache.org/viewvc/click/trunk/click/framework/src/org/apache/click/util/ClickUtils.java?rev=1023422&r1=1023421&r2=1023422&view=diff
==============================================================================
--- click/trunk/click/framework/src/org/apache/click/util/ClickUtils.java (original)
+++ click/trunk/click/framework/src/org/apache/click/util/ClickUtils.java Sun Oct 17 04:11:26 2010
@@ -61,6 +61,7 @@ import org.apache.click.Context;
import org.apache.click.Control;
import org.apache.click.Page;
import org.apache.click.ActionResult;
+import org.apache.click.Stateful;
import org.apache.click.control.AbstractControl;
import org.apache.click.control.AbstractLink;
import org.apache.click.control.ActionLink;
@@ -2566,6 +2567,112 @@ public class ClickUtils {
}
/**
+ * Remove the control state from the session for the given stateful control,
+ * control name and request context.
+ *
+ * @param control the stateful control which state to restore
+ * @param controlName the name of the control which state to restore
+ * @param context the request context
+ */
+ public static void removeState(Stateful control, String controlName, Context context) {
+ if (control == null) {
+ throw new IllegalStateException("Control cannot be null.");
+ }
+ if (controlName == null) {
+ throw new IllegalStateException(ClassUtils.getShortClassName(control.getClass())
+ + " name has not been set. State cannot be restored until the name is set");
+ }
+ if (context == null) {
+ throw new IllegalStateException("Context cannot be null.");
+ }
+
+ String resourcePath = context.getResourcePath();
+ Map pageMap = ClickUtils.getPageState(resourcePath, context);
+ if (pageMap != null) {
+ Object pop = pageMap.remove(controlName);
+
+ // Check if control state was emoved
+ if (pop != null) {
+ // If control state was removed, set session attribute to force
+ // session replication in a cluster
+ context.setSessionAttribute(resourcePath, pageMap);
+ }
+ }
+ }
+
+ /**
+ * Restore the control state from the session for the given stateful control,
+ * control name and request context.
+ * <p/>
+ * This method delegates to {@link org.apache.click.Stateful#setState(java.lang.Object)}
+ * to restore the control state.
+ *
+ * @param control the stateful control which state to restore
+ * @param controlName the name of the control which state to restore
+ * @param context the request context
+ */
+ public static void restoreState(Stateful control, String controlName, Context context) {
+ if (control == null) {
+ throw new IllegalStateException("Control cannot be null.");
+ }
+ if (controlName == null) {
+ throw new IllegalStateException(ClassUtils.getShortClassName(control.getClass())
+ + " name has not been set. State cannot be restored until the name is set");
+ }
+ if (context == null) {
+ throw new IllegalStateException("Context cannot be null.");
+ }
+
+ String resourcePath = context.getResourcePath();
+ Map pageMap = ClickUtils.getPageState(resourcePath, context);
+ if (pageMap != null) {
+ control.setState(pageMap.get(controlName));
+ }
+ }
+
+ /**
+ * Save the control state in the session for the given stateful control,
+ * control name and request context.
+ * <p/>
+ * * This method delegates to {@link org.apache.click.Stateful#getState()}
+ * to retrieve the control state to save.
+ *
+ * @param control the stateful control which state to save
+ * @param controlName the name of the control control which state to save
+ * @param context the request context
+ */
+ public static void saveState(Stateful control, String controlName, Context context) {
+ if (control == null) {
+ throw new IllegalStateException("Control cannot be null.");
+ }
+ if (controlName == null) {
+ throw new IllegalStateException(ClassUtils.getShortClassName(control.getClass())
+ + " name has not been set. State cannot be saved until the name is set");
+ }
+ if (context == null) {
+ throw new IllegalStateException("Context cannot be null.");
+ }
+
+ String resourcePath = context.getResourcePath();
+ Map pageMap = getOrCreatePageState(resourcePath, context);
+ Object state = control.getState();
+ if (state == null) {
+ // Set null state to see if it differs from previous state
+ Object pop = pageMap.put(controlName, state);
+ if(pop != null) {
+ // Previous state differs from current state, so set the
+ // session attribute to force session replication in a cluster
+ context.setSessionAttribute(resourcePath, pageMap);
+ }
+ } else {
+ pageMap.put(controlName, state);
+ // After control state has been added to the page state, set the
+ // session attribute to force session replication in a cluster
+ context.setSessionAttribute(resourcePath, pageMap);
+ }
+ }
+
+ /**
* Return the getter method name for the given property name.
*
* @param property the property name
@@ -3129,6 +3236,42 @@ public class ClickUtils {
}
/**
+ * Retrieve or create the map where page state is stored in.
+ *
+ * @see #getPageState(java.lang.String, org.apache.click.Context)
+ *
+ * @param pagePath the path under which the page state is stored in the
+ * session
+ * @param context the request context
+ * @return the map where page state is stored in
+ */
+ private static Map getOrCreatePageState(String pagePath, Context context) {
+ Map pageMap = getPageState(pagePath, context);
+ if (pageMap == null) {
+ pageMap = new HashMap();
+ }
+ return pageMap;
+ }
+
+ /**
+ * Retrieve the map for the given pagePath from the session where page state
+ * is stored in.
+ *
+ * @param pagePath the path under which the page state is stored in the
+ * session
+ * @param context the request context
+ * @return the map where page state is stored in
+ */
+ private static Map getPageState(String pagePath, Context context) {
+ Object storedPageValue = context.getSessionAttribute(pagePath);
+ Map pageMap = null;
+ if (storedPageValue != null) {
+ pageMap = (Map) storedPageValue;
+ }
+ return pageMap;
+ }
+
+ /**
* Invoke the named method on the given target object and return the result.
*
* @param target the target object with the method to invoke