basebugreport.java

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/*
   Copyright (C) 2003 MySQL AB
   
      This program is free software; you can redistribute it and/or modify
      it under the terms of the GNU General Public License as published by
      the Free Software Foundation; either version 2 of the License, or
      (at your option) any later version.
   
      This program 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 General Public License for more details.
   
      You should have received a copy of the GNU General Public License
      along with this program; if not, write to the Free Software
      Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
      
 */
package com.mysql.jdbc.util;

import java.sql.Connection;
import java.sql.SQLException;
import java.util.Properties;

import com.mysql.jdbc.Driver;

/**
 * Base class to help file bug reports for Connector/J.
 * 
 * <p>
 * MySQL AB <ul>really</ul> appreciates repeatable testcases
 * when reporting bugs, so we're giving you this class to make
 * that job a bit easier (and standarized).
 * 
 * <p>
 * To create a testcase, create a class that inherits from
 * this class (com.mysql.jdbc.util.BaseBugReport), and override
 * the methods 'setUp', 'tearDown' and 'runTest'. 
 * 
 * <p>
 * In the 'setUp' method, create code that creates your tables,
 * and populates them with any data needed to demonstrate the bug.
 * 
 * <p>
 * In the 'runTest' method, create code that demonstrates the bug 
 * using the tables and data you created in the 'setUp' method.
 * 
 * <p>
 * In the 'tearDown' method, drop any tables you created in the
 * 'setUp' method.
 * 
 * <p>
 * In any of the above three methods, you should use one
 * of the variants of the 'getConnection' method to create a 
 * JDBC connection to MySQL, which will use the default JDBC
 * URL of 'jdbc:mysql:///test'.  
 * 
 * <p>
 * If you need to use a JDBC URL that is different than 
 * 'jdbc:mysql:///test', then override the method 'getUrl' as well.
 * 
 * <p>
 * Use the 'assertTrue' methods to create conditions that must be
 * met in your testcase demonstrating the behavior you are expecting
 * (vs. the behavior you are observing, which is why you are most
 * likely filing a bug report).
 * 
 * <p>
 * Finally, create a 'main' method that creates a new instance
 * of your testcase, and calls the 'run' method:
 * 
 * <p><pre>
 * public static void main(String[] args) throws Exception {
 *      new MyBugReport().run();
 * }
 * </pre>
 * 
 * <p>
 * When filing a potential bug with MySQL Connector/J at 
 * http://bugs.mysql.com/ or on the bugs mailing list, please
 * include the code that you have just written using this class.
 * 
 * @author Mark Matthews
 * @version $Id: BaseBugReport.java,v 1.1.2.1 2003/09/17 18:01:22 mmatthew Exp $
 */
public abstract class BaseBugReport {
	
	private Connection conn;
	private Driver driver;
	
	/**
	 * Constructor for this BugReport, sets up
	 * JDBC driver used to create connections.
	 */
	protected BaseBugReport() {
		try {
			this.driver = new Driver();
		} catch (SQLException ex) {
			throw new RuntimeException(ex.toString());
		}
	}
	
	/**
	 * Override this method with code that sets up the 
	 * testcase for demonstrating your bug (creating tables,
	 * populating data, etc).
	 * 
	 * @throws Exception if an error occurs during the
	 * 'setUp' phase.
	 */
	public abstract void setUp() throws Exception;
	
	/**
	 * Override this method with code that cleans up 
	 * anything created in the setUp() method.
	 * 
	 * @throws Exception if an error occurs during the
	 * 'tearDown' phase.
	 */
	public abstract void tearDown() throws Exception;
	
	/**
	 * Override this method with code that demonstrates the bug. 
	 * This method will be called after setUp(), and before 
	 * tearDown().
	 * 
	 * @throws Exception if an error occurs during your test
	 * run.
	 */
	public abstract void runTest() throws Exception;
	
	/**
	 * Runs the testcase by calling the setUp(), runTest()
	 * and tearDown() methods. The tearDown() method is run
	 * regardless of any errors occuring in the other methods.
	 * 
	 * @throws Exception if an error occurs in any of the
	 * aforementioned methods.
	 */
	public final void run() throws Exception {
		try {
			setUp();
			runTest();
			
		} finally {
			tearDown();
		}
	}
	
	/**
	 * Throws an exception with the given message if condition
	 * evalutates to 'false'.
	 * 
	 * @param message the message to use in the exception
	 * @param condition the condition to test for
	 * @throws Exception if !condition
	 */
	protected final void assertTrue(String message, boolean condition) throws Exception {
		if (!condition) {
			throw new Exception("Assertion failed: " + message);
		}
	}
	
	/**
	 * Throws an exception if condition
	 * evalutates to 'false'.
     *
	 * @param condition the condition to test for
	 * @throws Exception if !condition
	 */
	protected final void assertTrue(boolean condition) throws Exception {
		assertTrue("(no message given)", condition);
	}
	
	/**
	 * Provides the JDBC URL to use to demonstrate the bug. The
	 * java.sql.Connection that you use to demonstrate this bug 
	 * will be provided by the getConnection() method using this URL.
	 * 
	 * The default value is 'jdbc:mysql:///test'
	 */
	public String getUrl() {
		return "jdbc:mysql:///test";
	}

	/**
	 * Provides a connection to the JDBC URL specified in getUrl().
	 * 
	 * If a connection already exists, that connection is returned.
	 * Otherwise a new connection is created.
	 * 
	 * @return a connection to the JDBC URL specified in getUrl().
	 * 
	 * @throws SQLException if an error is caused while creating the
	 * connection.
	 */
	public final synchronized Connection getConnection() throws SQLException {
		if (this.conn == null || this.conn.isClosed()) {
			this.conn = getNewConnection();
		}
		
		return this.conn;
	}
	
	/**
	 * Use this if you need to get a new connection for your 
	 * bug report (i.e. there's more than one connection involved).
	 * 
	 * @return a new connection to the JDBC URL specified in getUrl().
	 * 
	 * @throws SQLException if an error is caused while creating the
	 * connection.
	 */
	public final synchronized Connection getNewConnection() throws SQLException {
		return getConnection(getUrl());
	}

	/**
	 * Returns  a connection using the given URL.
	 * 
	 * @param url the JDBC URL to use
	 * @return a new java.sql.Connection to the JDBC URL.
	 * @throws SQLException if an error occurs getting the connection.
	 */
	public final synchronized Connection getConnection(String url) throws SQLException {
		return getConnection(url, null);
	}
	
	/**
	 * Returns  a connection using the given URL and properties.
	 * 
	 * @param url the JDBC URL to use
	 * @param props the JDBC properties to use
	 * @return a new java.sql.Connection to the JDBC URL.
	 * @throws SQLException if an error occurs getting the connection.
	 */
	public final synchronized Connection getConnection(String url, Properties props) throws SQLException {
		
		// Don't follow this example in your own code
		// This is to bypass the java.sql.DriverManager
		
		return this.driver.connect(url, props);
	}
}