Spring Framework example source code file (PortletRequestAttributes.java)

This example Spring Framework source code file (PortletRequestAttributes.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Spring Framework tags/keywords

illegalstateexception, iterator, map, object, object, portletrequest, portletrequestattributes, portletsession, portletsession, scope_global_session, scope_request, scope_request, string, string, util

The Spring Framework PortletRequestAttributes.java source code

/*
 * Copyright 2002-2008 the original author or authors.
 *
 * 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.springframework.web.portlet.context;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import javax.portlet.PortletRequest;
import javax.portlet.PortletSession;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.util.Assert;
import org.springframework.util.StringUtils;
import org.springframework.web.context.request.AbstractRequestAttributes;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.portlet.util.PortletUtils;

/**
 * Portlet-based implementation of the
 * {@link org.springframework.web.context.request.RequestAttributes} interface.
 *
 * <p>Accesses objects from portlet request and portlet session scope,
 * with a distinction between "session" (the PortletSession's "portlet scope")
 * and "global session" (the PortletSession's "application scope").
 *
 * @author Juergen Hoeller
 * @since 2.0
 * @see javax.portlet.PortletRequest#getAttribute
 * @see javax.portlet.PortletSession#getAttribute
 * @see javax.portlet.PortletSession#PORTLET_SCOPE
 * @see javax.portlet.PortletSession#APPLICATION_SCOPE
 * @see RequestAttributes#SCOPE_SESSION
 * @see RequestAttributes#SCOPE_GLOBAL_SESSION
 */
public class PortletRequestAttributes extends AbstractRequestAttributes {

	/**
	 * We'll create a lot of these objects, so we don't want a new logger every time.
	 */
	private static final Log logger = LogFactory.getLog(PortletRequestAttributes.class);


	private final PortletRequest request;

	private PortletSession session;

	private final Map sessionAttributesToUpdate = new HashMap();

	private final Map globalSessionAttributesToUpdate = new HashMap();


	/**
	 * Create a new PortletRequestAttributes instance for the given request.
	 * @param request current portlet request
	 */
	public PortletRequestAttributes(PortletRequest request) {
		Assert.notNull(request, "Request must not be null");
		this.request = request;
		// Fetch existing session reference early, to have it available even
		// after request completion (for example, in a custom child thread).
		this.session = request.getPortletSession(false);
	}


	/**
	 * Exposes the native {@link PortletRequest} that we're wrapping.
	 */
	public final PortletRequest getRequest() {
		return this.request;
	}

	/**
	 * Exposes the {@link PortletSession} that we're wrapping.
	 * @param allowCreate whether to allow creation of a new session if none exists yet
	 */
	protected final PortletSession getSession(boolean allowCreate) {
		try {
			this.session = this.request.getPortletSession(allowCreate);
			return this.session;
		}
		catch (IllegalStateException ex) {
			// Couldn't access session... let's check why.
			if (this.session == null) {
				// No matter what happened - we cannot offer a session.
				throw ex;
			}
			// We have a fallback session reference...
			// Let's see whether it is appropriate to return it.
			if (allowCreate) {
				boolean canAskForExistingSession = false;
				try {
					this.session = this.request.getPortletSession(false);
					canAskForExistingSession = true;
				}
				catch (IllegalStateException ex2) {
				}
				if (canAskForExistingSession) {
					// Could ask for existing session, hence the IllegalStateException
					// came from trying to create a new session too late -> rethrow.
					throw ex;
				}
			}
			// Else: Could not even ask for existing session, hence we assume that
			// the request has been completed and the session is accessed later on
			// (for example, in a custom child thread).
			return this.session;
		}
	}


	public Object getAttribute(String name, int scope) {
		if (scope == SCOPE_REQUEST) {
			return this.request.getAttribute(name);
		}
		else {
			PortletSession session = getSession(false);
			if (session != null) {
				if (scope == SCOPE_GLOBAL_SESSION) {
					Object value = session.getAttribute(name, PortletSession.APPLICATION_SCOPE);
					if (value != null) {
						this.globalSessionAttributesToUpdate.put(name, value);
					}
					return value;
				}
				else {
					Object value = session.getAttribute(name);
					if (value != null) {
						this.sessionAttributesToUpdate.put(name, value);
					}
					return value;
				}
			}
			else {
				return null;
			}
		}
	}

	public void setAttribute(String name, Object value, int scope) {
		if (scope == SCOPE_REQUEST) {
			this.request.setAttribute(name, value);
		}
		else {
			PortletSession session = getSession(true);
			if (scope == SCOPE_GLOBAL_SESSION) {
				session.setAttribute(name, value, PortletSession.APPLICATION_SCOPE);
				this.globalSessionAttributesToUpdate.remove(name);
			}
			else {
				session.setAttribute(name, value);
				this.sessionAttributesToUpdate.remove(name);
			}
		}
	}

	public void removeAttribute(String name, int scope) {
		if (scope == SCOPE_REQUEST) {
			this.request.removeAttribute(name);
			removeRequestDestructionCallback(name);
		}
		else {
			PortletSession session = getSession(false);
			if (session != null) {
				if (scope == SCOPE_GLOBAL_SESSION) {
					session.removeAttribute(name, PortletSession.APPLICATION_SCOPE);
					this.globalSessionAttributesToUpdate.remove(name);
				}
				else {
					session.removeAttribute(name);
					this.sessionAttributesToUpdate.remove(name);
				}
			}
		}
	}

	public String[] getAttributeNames(int scope) {
		if (scope == SCOPE_REQUEST) {
			return StringUtils.toStringArray(this.request.getAttributeNames());
		}
		else {
			PortletSession session = getSession(false);
			if (session != null) {
				if (scope == SCOPE_GLOBAL_SESSION) {
					return StringUtils.toStringArray(session.getAttributeNames(PortletSession.APPLICATION_SCOPE));
				}
				else {
					return StringUtils.toStringArray(session.getAttributeNames());
				}
			}
			else {
				return new String[0];
			}
		}
	}

	public void registerDestructionCallback(String name, Runnable callback, int scope) {
		if (scope == SCOPE_REQUEST) {
			registerRequestDestructionCallback(name, callback);
		}
		else {
			registerSessionDestructionCallback(name, callback);
		}
	}

	public String getSessionId() {
		return getSession(true).getId();
	}

	public Object getSessionMutex() {
		return PortletUtils.getSessionMutex(getSession(true));
	}


	/**
	 * Update all accessed session attributes through <code>session.setAttribute
	 * calls, explicitly indicating to the container that they might have been modified.
	 */
	protected void updateAccessedSessionAttributes() {
		PortletSession session = this.request.getPortletSession(false);
		if (session != null) {
			for (Iterator it = this.sessionAttributesToUpdate.entrySet().iterator(); it.hasNext();) {
				Map.Entry entry = (Map.Entry) it.next();
				String name = (String) entry.getKey();
				Object newValue = entry.getValue();
				Object oldValue = session.getAttribute(name);
				if (oldValue == newValue) {
					session.setAttribute(name, newValue);
				}
			}
			for (Iterator it = this.globalSessionAttributesToUpdate.entrySet().iterator(); it.hasNext();) {
				Map.Entry entry = (Map.Entry) it.next();
				String name = (String) entry.getKey();
				Object newValue = entry.getValue();
				Object oldValue = session.getAttribute(name, PortletSession.APPLICATION_SCOPE);
				if (oldValue == newValue) {
					session.setAttribute(name, newValue, PortletSession.APPLICATION_SCOPE);
				}
			}
		}
		this.sessionAttributesToUpdate.clear();
		this.globalSessionAttributesToUpdate.clear();
	}

	/**
	 * Register the given callback as to be executed after session termination.
	 * @param name the name of the attribute to register the callback for
	 * @param callback the callback to be executed for destruction
	 */
	private void registerSessionDestructionCallback(String name, Runnable callback) {
		if (logger.isWarnEnabled()) {
			logger.warn("Could not register destruction callback [" + callback + "] for attribute '" + name +
					"' for session scope because Portlet API 1.0 does not support session attribute callbacks");
		}
	}


	public String toString() {
		return this.request.toString();
	}

}