jforum example source code file (JForumExecutionContext.java)

This example jforum source code file (JForumExecutionContext.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 - jforum tags/keywords

configuration, connection, connection, error, exception, exception, forumcontext, http, jdbc, jforum, jforumexecutioncontext, jforumexecutioncontext, request, response, servlet, simplehash, sql, string, string, threadlocal

The jforum JForumExecutionContext.java source code

/*
 * Copyright (c) JForum Team
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, 
 * with or without modification, are permitted provided 
 * that the following conditions are met:
 * 
 * 1) Redistributions of source code must retain the above 
 * copyright notice, this list of conditions and the 
 * following  disclaimer.
 * 2)  Redistributions in binary form must reproduce the 
 * above copyright notice, this list of conditions and 
 * the following disclaimer in the documentation and/or 
 * other materials provided with the distribution.
 * 3) Neither the name of "Rafael Steil" nor 
 * the names of its contributors may be used to endorse 
 * or promote products derived from this software without 
 * specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT 
 * HOLDERS AND CONTRIBUTORS "AS IS" AND ANY 
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, 
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR 
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 
 * THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE 
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES 
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, 
 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 
 * IN CONTRACT, STRICT LIABILITY, OR TORT 
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE
 * 
 * This file creation date: 29/01/2006 - 12:19:11
 * The JForum Project
 * http://www.jforum.net
 */
package net.jforum;

import java.io.IOException;
import java.sql.Connection;

import javax.servlet.http.HttpServletResponse;

import net.jforum.context.RequestContext;
import net.jforum.context.ResponseContext;
import net.jforum.context.ForumContext;
import net.jforum.exceptions.ForumException;
import net.jforum.util.preferences.ConfigKeys;
import net.jforum.util.preferences.SystemGlobals;

import org.apache.log4j.Logger;

import freemarker.template.Configuration;
import freemarker.template.ObjectWrapper;
import freemarker.template.SimpleHash;

/**
 * Data execution context. 
 * 
 * @author Rafael Steil
 * @version $Id: JForumExecutionContext.java,v 1.10 2006/10/10 01:59:55 rafaelsteil Exp $
 */
public class JForumExecutionContext
{
    private static ThreadLocal userData = new ThreadLocal();
	private static Logger logger = Logger.getLogger(JForumExecutionContext.class);
	private static Configuration templateConfig;
	
	private Connection conn;
    private ForumContext forumContext;
    private SimpleHash context = new SimpleHash(ObjectWrapper.BEANS_WRAPPER);
    private String redirectTo;
    private String contentType;
    private boolean isCustomContent;
    private boolean enableRollback;
	
	/**
	 * Gets the execution context.
	 * @return JForumExecutionContext
	 */
	public static JForumExecutionContext get()
	{
		JForumExecutionContext ex = (JForumExecutionContext)userData.get();

		if (ex == null) {
			ex = new JForumExecutionContext();
			userData.set(ex);
		}
		
		return ex;
	}
	
	/**
	 * Checks if there is an execution context already set
	 * @return <code>true if there is an execution context
	 * @see #get()
	 */
	public static boolean exists()
	{
		return (userData.get() != null);
	}
	
	/**
	 * Sets the default template configuration 
	 * @param config The template configuration to set
	 */
	public static void setTemplateConfig(Configuration config)
	{
		templateConfig = config;
	}
	
	/**
	 * Gets a reference to the default template configuration settings.
	 * @return The template configuration instance
	 */
	public static Configuration templateConfig()
	{
		return templateConfig;
	}
	
	/**
	 * Sets the execution context
	 * @param ex JForumExecutionContext
	 */
	public static void set(JForumExecutionContext ex)
	{
		userData.set(ex);
	}
	
	/**
	 * Sets a connection
	 * @param conn The connection to use
	 */
	public void setConnection(Connection conn)
	{
		this.conn = conn;
	}
	
	/**
	 * Gets the current thread's connection
	 * @return Connection
	 */
	public static Connection getConnection() 
	{
		return getConnection(true);
	}
	
	public static Connection getConnection(boolean validate)
	{
		JForumExecutionContext ex = get();
		Connection c =  ex.conn;
		
		if (validate && c == null) {
			c = DBConnection.getImplementation().getConnection();
			
			try {
				c.setAutoCommit(!SystemGlobals.getBoolValue(ConfigKeys.DATABASE_USE_TRANSACTIONS));
			}
			catch (Exception e) {
                //catch error autocommit
            }
			
			ex.setConnection(c);
			set(ex);
		}
	    
		return c; 
	}

    public static ForumContext getForumContext()
    {
        return ((JForumExecutionContext)userData.get()).forumContext;
    }

    public void setForumContext(ForumContext forumContext)
    {
        this.forumContext = forumContext;
    }

    /**
	 * Gets the current thread's request
	 * @return WebContextRequest
	 */
	public static RequestContext getRequest() {
		return getForumContext().getRequest();
	}
	
	/**
	 * Gets the current thread's response
	 * @return HttpServletResponse
	 */
	public static ResponseContext getResponse() {
		return getForumContext().getResponse();
	}

	/**
	 * Gets the current thread's template context
	 * @return SimpleHash
	 */
	public static SimpleHash getTemplateContext() {
		return ((JForumExecutionContext)userData.get()).context;
	}

	/**
	 * Gets the current thread's <code>DataHolder instance
     * @param redirect String
     */
	public static void setRedirect(String redirect) {
		((JForumExecutionContext)userData.get()).redirectTo = redirect;
	}

	/**
	 * Sets the content type for the current http response.
	 * @param contentType String
	 */
	public static void setContentType(String contentType) {
		((JForumExecutionContext)userData.get()).contentType = contentType;
	}
	
	/**
	 * Gets the content type for the current request.
	 * @return String
	 */
	public static String getContentType()
	{
		return ((JForumExecutionContext)userData.get()).contentType;
	}

	/**
	 * Gets the URL to redirect to, if any.
	 * @return The URL to redirect, of <code>null if none.
	 */
	public static String getRedirectTo()
	{
		JForumExecutionContext ex = (JForumExecutionContext)userData.get();
		return (ex != null ? ex.redirectTo : null);
	}

	/**
	 * Marks the request to use a binary content-type.
	 * @param enable boolean
	 */
	public static void enableCustomContent(boolean enable) {
		((JForumExecutionContext)userData.get()).isCustomContent = enable;
	}
	
	/**
	 * Checks if the current request is binary
	 * @return <code>true if the content tyee for the current request is 
	 * any binary data.
	 */
	public static boolean isCustomContent()
	{
		return ((JForumExecutionContext)userData.get()).isCustomContent;
	}

	/**
	 * Forces the request to not commit the connection.
	 */
	public static void enableRollback() {
		((JForumExecutionContext)userData.get()).enableRollback = true;
	}

	/**
	 * Check if commit is disabled or not for the current request.
	 * @return <code>true if a commit should NOT be made
	 */
	public static boolean shouldRollback() {
		return ((JForumExecutionContext)userData.get()).enableRollback;
	}

    /**
     * Send UNAUTHORIZED to the browser and ask user to login via basic authentication
     */
	public static void requestBasicAuthentication()  
	{
		getResponse().addHeader("WWW-Authenticate", "Basic realm=\"JForum\"");
		
		try {
			getResponse().sendError(HttpServletResponse.SC_UNAUTHORIZED);
		}
		catch (IOException e) {
			throw new ForumException(e);
		}
		
		enableCustomContent(true);
    }
	
	/**
	 * Finishes the execution context
	 */
	public static void finish()
	{
		Connection conn = JForumExecutionContext.getConnection(false);
		
		if (conn != null) {
			if (SystemGlobals.getBoolValue(ConfigKeys.DATABASE_USE_TRANSACTIONS)) {
				if (JForumExecutionContext.shouldRollback()) {
					try {
						conn.rollback();
					}
					catch (Exception e) {
						logger.error("Error while rolling back a transaction", e);
					}
				}
				else {
					try {
						conn.commit();
					}
					catch (Exception e) {
						logger.error("Error while commiting a transaction", e);
					}
				}
			}
			
			try {
				DBConnection.getImplementation().releaseConnection(conn);
			}
			catch (Exception e) {
				logger.error("Error while releasing the connection : " + e, e);
			}
		}
		
		userData.set(null);
	}
}