JDBC连接数据库和释放连接
欢迎进入Java社区论坛,与200万技术人员互动交流 >>进入 用久了hibernate现在对于JDBC是怎么实现数据库的连接和释放,所以特地总结下关于JDBC的知识,目的是用于提醒自己很多Java的基础知识需要健全。 package com.ssh.action; import java.sql.Connection;
欢迎进入Java社区论坛,与200万技术人员互动交流 >>进入
用久了hibernate现在对于JDBC是怎么实现数据库的连接和释放,所以特地总结下关于JDBC的知识,目的是用于提醒自己很多Java的基础知识需要健全。
package com.ssh.action;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
/**
* 数据库工具类
* @author Administrator
*
*/
public class DBUtil {
/**
* 取得数据库连接
* @return
*/
public static Connection getConnection() {
Connection conn = null;
try {
//取得jdbc配置信息
JdbcInfo jdbcInfo =null; ///ConfigReader.getInstance().getJdbcInfo();
Class.forName(jdbcInfo.getDriverName());
conn = DriverManager.getConnection(jdbcInfo.getUrl(), jdbcInfo.getUsername(), jdbcInfo.getPassword());
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
return conn;
}
/**
* 关闭 PreparedStatement(预处理执行语句) 目的:可以防止SQL注入、在特定的驱动数据库下相对效率要高(不绝对)、不需要频繁编译.因为已经预加载了
* @param pstmt
*/
public static void close(PreparedStatement pstmt) {
if (pstmt != null) {
try {
pstmt.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
/**
* 关闭连接
* @param conn
*/
public static void close(Connection conn) {
if (conn != null) {
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
/**
* 关闭数据库结果集的数据表
* @param rs
*/
public static void close(ResultSet rs) {
if (rs != null) {
try {
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
/**
* 提交事务
* @param conn
*/
public static void commit(Connection conn) {
if (conn != null) {
try {
conn.commit();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
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