package com.amuos.jdbc.curd;import java.sql.Connection;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;import com.amuos.jdbc.util.JdbcUtils;/** *  * 2015-1-25 *  * @author <a href="mailto:472846889@qq.com">王娟</a> *  */public class CRUD {    /**     * @param args     * @throws SQLException     *///    public static void main(String[] args) throws SQLException {////         create();////         read();////         update();////         delete();//    }    static void delete() throws SQLException {        Connection conn = null;        Statement st = null;        ResultSet rs = null;        try {            // 2.建立连接            conn = JdbcUtils.getConnection();            // conn = JdbcUtilsSing.getInstance().getConnection();            // 3.创建语句            st = conn.createStatement();            String sql = "delete from contacts where id = 2";            // 4.执行语句            int i = st.executeUpdate(sql);            System.out.println("Have deleted " + i + " row.");        } finally {            JdbcUtils.free(rs, st, conn);        }    }    static void update() throws SQLException {        Connection conn = null;        Statement st = null;        ResultSet rs = null;        try {            // 2.建立连接            conn = JdbcUtils.getConnection();            // conn = JdbcUtilsSing.getInstance().getConnection();            // 3.创建语句            st = conn.createStatement();            String sql = "update contacts set mail2 = ‘test@163.com‘ where name = ‘test‘ ";            // 4.执行语句            int i = st.executeUpdate(sql);            System.out.println("Have updated " + i + " row.");        } finally {            JdbcUtils.free(rs, st, conn);        }    }    static void create() throws SQLException {        Connection conn = null;        Statement st = null;        ResultSet rs = null;        try {            // 2.建立连接            conn = JdbcUtils.getConnection();            // conn = JdbcUtilsSing.getInstance().getConnection();            // 3.创建语句            st = conn.createStatement();            String sql = "insert into contacts(name,main,mail1,mail2,relationship) values (‘test‘, ‘1234565‘, ‘test@test.com‘,‘‘,‘同事‘) ";            // 4.执行语句            int i = st.executeUpdate(sql);            System.out.println("Have inserted " + i + " row into table contacts.");        } finally {            JdbcUtils.free(rs, st, conn);        }    }    static void read() throws SQLException {        Connection conn = null;        Statement st = null;        ResultSet rs = null;        try {            // 2.建立连接            conn = JdbcUtils.getConnection();            // conn = JdbcUtilsSing.getInstance().getConnection();            // 3.创建语句            st = conn.createStatement();            // 4.执行语句            rs = st.executeQuery("select id, name, birthday, mobile  from contacts");            // 5.处理结果            while (rs.next()) {                System.out.println(rs.getObject("id") + "\t"                        + rs.getObject("name") + "\t"                        + rs.getObject("birthday") + "\t"                        + rs.getObject("mobile"));            }        } finally {            JdbcUtils.free(rs, st, conn);        }    }}