JDBC连接数据库(适当的封装查询、新增修改删除)的方法

package com.connection.ConnCommit;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.ResultSetMetaData;import java.sql.SQLException;import java.sql.Statement;/** *  * @Detail :JDBC连接数据库 * @Author: 韩庆 * @E-mail: [e-mail] * @Date: 2012-11-12 * @Time: 下午10:32:31 *  */public class JDBCConnCommit {private static String url = "jdbc:mysql://localhost:3306/nms";private static String user = "root";private static String password = "root";public Connection getConnection() {Connection conn = null;try {Class.forName("com.mysql.jdbc.Driver");conn = DriverManager.getConnection(url, user, password);} catch (ClassNotFoundException e) {e.printStackTrace();System.out.println("类未发现异常...");} catch (SQLException e) {e.printStackTrace();System.out.println("SQL异常....");} catch (Exception e) {e.printStackTrace();System.out.println("出现异常：" + e.getMessage());}return conn;}/** * 执行查询操作 *  * @param conn *            数据库连接 * @param sql *            需要执行的sql语句 * @throws Exception */public void createSQLQuery(Connection conn, String sql) throws Exception {Statement stmt = null;ResultSet rs = null;try {if (null == conn) {throw new Exception("连接为空！请检查数据库连接！");}if (null == sql || "".equals(sql)) {throw new Exception("sql语句为空！");}stmt = conn.createStatement();rs = stmt.executeQuery(sql);ResultSetMetaData rsmd = rs.getMetaData();// 用于得到字段个数int cCount = rsmd.getColumnCount();// 遍历每条数据 内部根据个人需求可做相应的处理while (rs.next()) {for (int i = 0; i < cCount; i++) {// String Str = rs.getString(i+1);// 做相应处理}}} catch (SQLException e) {System.out.println(e.getMessage());} catch (Exception e) {e.printStackTrace();} finally {if (null != rs) {rs.close();}if (null != stmt) {stmt.close();}/* * if (null != null) { conn.close(); * }//如果单纯的使用一次的话，则连接可以关闭createSQLExecute方法中也是 */}}/** * 执行sql的添加、修改、删除操作 *  * @param conn * @param sql */public void createSQLExecute(Connection conn, String sql) {// 有关conn和sql为空的问题，处理同上，省略。。。Statement stmt = null;try {stmt = conn.createStatement();int i = stmt.executeUpdate(sql);if (i > 0) {System.out.println("处理成功！处理条数为" + i);} else {System.out.println("处理有误！");}} catch (Exception e) {// 应该异常分类处理，这里省略} finally {try {if (null != stmt) {stmt.close();}} catch (SQLException e) {e.printStackTrace();}}}/** * 测试样例 */public void exampleDome() {JDBCConnCommit jdbcCc = new JDBCConnCommit();Connection conn = jdbcCc.getConnection();// 得到连接try {conn.setAutoCommit(false);// 不自动提交事务String queryString = "";// 声明sql语句// 测试添加queryString = "insert into Table_Name(name,sex,age) values('hank','male',22)";jdbcCc.createSQLExecute(conn, queryString);// 测试查询queryString = "select * from Table_Name where name like '%韩%'";jdbcCc.createSQLQuery(conn, queryString);// 测试删除queryString = "delete from Table_Name where name='hank'";jdbcCc.createSQLExecute(conn, queryString);conn.commit();// 正常处理完后 提交事务} catch (SQLException e) {// ...} catch (Exception e) {e.printStackTrace();} finally {try {if (null != conn) {conn.close();// 关闭连接}} catch (SQLException e) {e.printStackTrace();}}}}

//刚刚发现 修改测试让我忘记了~~sorry 纯手敲，错误难免。 以上例子受《Java编程百例》影响而写。代码稍后上传至资源。

//补充下：又看了下代码：当sql执行错误或者说异常后，事务需要回滚即 conn.rollback()，dome方法里忘记添加了。sorry...