简单jdbc实例______软件开发-JAVA

package com.jdbc.db;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.Statement;public class DBUtil {public static void main(String[] args) throws Exception {//1.加载驱动(注册)Class.forName("oracle.jdbc.driver.OracleDriver");//2.建立连接(连接数据库)Connection conn = DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:xe","system","1234");//3.通过连接创建语句对象Statement state = conn.createStatement();String sql = "select * from emp";//4.执行SQL、接收返回数据ResultSet res = state.executeQuery(sql);while(res.next()){//int id = res.getInt(1);//String name = res.getString(2);//String job = res.getString(3);//int mgr = res.getInt(4);//String hirdate = res.getString(5);//String sal = res.getString(6);//String comm = res.getString(7);//String deptno = res.getString(8);String id = res.getString("empno");String name = res.getString("ename");String job = res.getString("job");String mgr = res.getString("mgr");String hirdate = res.getString("hirdate");String sal = res.getString("sal");String comm = res.getString("comm");String deptno = res.getString("deptno");System.out.println(id+","+name+","+job+","+mgr+","+hirdate+","+sal+","+comm+","+deptno);}res.close();state.close();conn.close();}}

上面那个是最普通的JDBC的写法...下面来一个稍微文艺点的...

package com.jdbc.db;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.Statement;public class DBUtil2 {public static void main(String[] args) {Connection conn = null;Statement state = null;ResultSet res = null;String sql = "select * from emp";try{Class.forName("oracle.jdbc.driver.OracleDriver");conn = DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:xe","system","1234");state = conn.createStatement();res = state.executeQuery(sql);while(res.next()){String id = res.getString("empno");String name = res.getString("ename");String job = res.getString("job");String mgr = res.getString("mgr");String hirdate = res.getString("hirdate");String sal = res.getString("sal");String comm = res.getString("comm");String deptno = res.getString("deptno");System.out.println(id+","+name+","+job+","+mgr+","+hirdate+","+sal+","+comm+","+deptno);}}catch(Exception e){e.printStackTrace();}finally{//关闭try{if(res != null){res.close();res = null;//设置为null，方便垃圾收集器随时将其回收(关系不太大)}if(state != null){state.close();state = null;}if(conn != null){conn.close();conn = null;}}catch(Exception e){e.printStackTrace();}}}}

全文完.....

添加于2015-12-10

感觉自己还是没什么长进啊...

MySql 版本

package com.jdbc.test;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.Statement;/** * 测试练习JDBC-MySql * @author cyx * */public class JDBC_Test {public static void main(String[] args) {String url = "jdbc:mysql://localhost:3306/jdbc_test";//连接数据库的URLString username = "root";//数据库的用户名String password = "1234";//数据库的密码try{//1.加载驱动Class.forName("com.mysql.jdbc.Driver");//2.创建数据库连接对象Connection conn = DriverManager.getConnection(url,username,password);//3.创建Statement对象Statement state = conn.createStatement();//4.获取ResultSet对象String sql = "SELECT * FROM TEST1";ResultSet res = state.executeQuery(sql);while(res.next()){String id = res.getString("id");String user = res.getString("username");String pw = res.getString("password");System.out.println(id+" "+user+" "+pw);}//5.关闭数据库连接res.close();state.close();conn.close();}catch(Exception e){e.printStackTrace();}}}

版本2

package com.jdbc.test;import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.Statement;import java.util.ArrayList;import java.util.List;import com.jdbc.entity.User;public class JDBC_Test2 {private String url = "jdbc:mysql://localhost:3306/jdbc_test";private String username = "root";private String password = "1234";public static void main(String[] args) {JDBC_Test2 jt = new JDBC_Test2();List<User> list = jt.findAll();for (User user : list) {System.out.println(user);}}public List<User> findAll(){List<User> list = new ArrayList<User>();try{String sql = "SELECT * FROM TEST1";//1.加载驱动Class.forName("com.mysql.jdbc.Driver");//2.创建数据库连接对象Connection conn = DriverManager.getConnection(url,username,password);//3.创建Statement对象Statement state = conn.createStatement();ResultSet res = state.executeQuery(sql);while(res.next()){User user = new User();user.setId(res.getString("id"));user.setUsername(res.getString("username"));user.setPassword(res.getString("password"));list.add(user);}res.close();state.close();conn.close();}catch(Exception e){e.printStackTrace();}return list;}}

版本3

package com.jdbc.test;import java.sql.Connection;import java.sql.DriverManager;import java.sql.Statement;import com.jdbc.entity.User;public class JDBC_Test3 {public static void main(String[] args) {JDBC_Test3 jt = new JDBC_Test3();User user = new User();user.setId("1");user.setUsername("ycy");user.setPassword("1234");jt.insert(user);}public void insert(User user){String sql = "INSERT INTO TEST1 VALUES("+user.getId()+",'"+user.getUsername()+"','"+user.getPassword()+"')";Statement state = getStatement();try{int result = state.executeUpdate(sql);if(result < 0){throw new Exception("插入数据库错误..");}else{System.out.println("插入了"+result+" 条数据");}}catch(Exception e){e.printStackTrace();}}public Statement getStatement(){String url = "jdbc:mysql://localhost:3306/jdbc_test";String username = "root";String password ="1234";Statement state = null;try{//1.加载驱动Class.forName("com.mysql.jdbc.Driver");//2.创建数据库连接对象Connection conn = DriverManager.getConnection(url,username,password);//3.创建Statement对象state = conn.createStatement();}catch(Exception e){e.printStackTrace();}return state;}}

package com.jdbc.test;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.ResultSet;public class JDBC_Test4 {public static void main(String[] args) throws Exception {JDBC_Test4 jt = new JDBC_Test4();jt.Login("cyx", "123456");}public void Login(String username ,String password) throws Exception{String url = "jdbc:mysql://localhost:3306/jdbc_test";String un = "root";String pw ="1234";Connection conn = null;PreparedStatement pst = null;ResultSet rs = null;try{Class.forName("com.mysql.jdbc.Driver");conn = DriverManager.getConnection(url,un,pw);//设置默认提交为falseconn.setAutoCommit(false);String sql = "SELECT USERNAME,PASSWORD FROM TEST1 WHERE USERNAME = ? AND PASSWORD = ?";pst = conn.prepareStatement(sql);pst.setString(1, username);pst.setString(2, password);System.out.println(pst.toString());rs = pst.executeQuery();if(rs.next()){System.out.println("登陆成功");}else{System.out.println("登录失败");}conn.commit();}catch(Exception e){conn.rollback();e.printStackTrace();}finally{if(rs != null){rs.close();}if(pst != null){pst.close();}if(conn != null){conn.close();}}}}

//更新与2015-12-13

封装了一个Connection,使用链接时候直接获取,不用再写好几遍了....

package com.struts_extjs_test.utils;import java.io.InputStream;import java.sql.Connection;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.util.Properties;import javax.sql.DataSource;import org.apache.commons.dbcp.BasicDataSourceFactory;public class JDBC {private static Properties p = null;private static DataSource ds = null;static{//解析properties文件p = new Properties();InputStream in = JDBC.class.getClassLoader().getResourceAsStream("MySqlDb.properties");try{p.load(in);ds = BasicDataSourceFactory.createDataSource(p);}catch(Exception e){e.printStackTrace();}}public static Connection getConnection() throws Exception{Connection conn = ds.getConnection();return conn;}public static void close(ResultSet rs ,PreparedStatement stmt, Connection conn){try{if(rs != null && !rs.isClosed()){rs.close();}if(stmt != null && !stmt.isClosed()){stmt.close();}if(conn != null && !conn.isClosed()){conn.close();}}catch(Exception e){e.printStackTrace();}}}