JDBC连接数据库问题-请各位高手给与解答
咋个办呢 2009-08-19 12:16:44
package org.bkzx.db.conn;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import org.apache.log4j.Logger;
import org.bkzx.log.SystemRunLog;
/**
* 连接数据的静态类
* @author ai_zxc
* @version 2009.08.18
*/
public class DB_Connection {
private static Logger log = SystemRunLog.getLogger(DB_Connection.class) ;
private final static String URL = "jdbc:mysql://192.168.2.4:3306/BKZX" ;
private final static String USER = "root" ;
private final static String PASSWORD = "******" ;
public static Connection conn = null ;
/**
* 获取连数据对象
* @return Connection 数据库连接对象
*/
public static Connection getConn() {
try {
Class.forName("com.mysql.jdbc.Driver") ;
conn = DriverManager.getConnection(URL, USER, PASSWORD) ;
System.out.println(conn);
} catch (ClassNotFoundException e) {
log.error("连接数据失败:", e) ;
e.printStackTrace();
} catch (SQLException e) {
log.error("连接数据失败:", e) ;
e.printStackTrace();
}
return conn;
}
public static boolean closeConn(){
try {
conn.close() ;
// DB_Connection.conn = null ;
return true ;
} catch (SQLException e) {
log.error("关闭数据库失败!", e) ;
// DB_Connection.conn = null ;
e.printStackTrace();
return false ;
}
}
}
//*****************************************************************************************
package org.bkzx.test.db;
import java.sql.Connection;
import org.bkzx.db.conn.DB_Connection;
import junit.framework.TestCase;
public class BDConnTest extends TestCase {
public void testConn(){
if(null != DB_Connection.getConn()){
System.out.println("数据连接成功! conn:"+ DB_Connection.conn);
}
else{
System.out.println("数据库连接失败!conn: " + DB_Connection.conn);
}
if(DB_Connection.closeConn()){
System.out.println("关闭数据连接成功! conn:"+ DB_Connection.conn);
}
else{
System.out.println("关闭数据库连接失败!conn: " + DB_Connection.conn);
}
}
}
//***********************************
输出:
com.mysql.jdbc.Connection@14b7453
数据连接成功! conn:com.mysql.jdbc.Connection@14b7453
关闭数据连接成功! conn:com.mysql.jdbc.Connection@14b7453
//******************************************
问题:
为什么!关闭数据连接成功! conn:com.mysql.jdbc.Connection@14b7453 不是null 呢?
我的邮箱是:ai_zxc@163.com
谢谢各位高人了。