Spring + JdbcTemplate + JdbcDaoSupport__spring

首先，資料庫是這樣的，很簡單。

當然，要引入spring的包，這裡我全部匯入了，省事。

applicationContext.xml是這樣的：

<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="    http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd"><bean id="test" class="jdbc.Test">    <property name="dataSource" ref="dataSource"></property></bean><bean id="dataSource"class="org.springframework.jdbc.datasource.DriverManagerDataSource"><property name="driverClassName" value="com.mysql.jdbc.Driver" /><property name="url" value="jdbc:mysql://localhost:3306/testspring" /><property name="username" value="root" /><property name="password" value="" /></bean></beans>

User.java是這樣的：

package jdbc;public class User {private int id;private String name;private String password;public int getId() {return id;}public void setId(int id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getPassword() {return password;}public void setPassword(String password) {this.password = password;}}

下面來對比一下三種寫法：

1、spring

package jdbc;import java.sql.Connection;import java.sql.PreparedStatement;import java.sql.SQLException;import javax.sql.DataSource;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;public class Test {private DataSource dataSource;public void setDataSource(DataSource dataSource) {this.dataSource = dataSource;}public void insert(User u) {String sql = "insert into _user " + "values(null, ?, ?)";//普通的sql語句Connection conn = null;try {conn = dataSource.getConnection();PreparedStatement ps = conn.prepareStatement(sql);ps.setString(1, u.getName());ps.setString(2, u.getPassword());ps.executeUpdate();ps.close();} catch (SQLException e) {throw new RuntimeException(e);} finally {if (conn != null) {try {conn.close();} catch (SQLException e) {}}}}public static void main(String[] args) {ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");Test t = (Test) ctx.getBean("test");User u = new User();u.setName("dd");u.setPassword("dd");t.insert(u);}}

運行結果是這樣的：

2、JdbcTemplate 

package jdbc;import java.sql.Connection;import java.sql.PreparedStatement;import java.sql.SQLException;import javax.sql.DataSource;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;import org.springframework.jdbc.core.JdbcTemplate;public class Test {private DataSource dataSource;public void setDataSource(DataSource dataSource) {this.dataSource = dataSource;}public void insert(User u) {String sql = "insert into _user " + "values(null, ?, ?)";//普通的sql語句JdbcTemplate template = new JdbcTemplate(dataSource);template.update(sql, new Object[]{u.getName(), u.getPassword()});}public static void main(String[] args) {ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");Test t = (Test) ctx.getBean("test");User u = new User();u.setName("dd");u.setPassword("dd");t.insert(u);}}

可以看得出簡單了很多，不用Connection了。

3、JdbcDaoSupport

這個更簡單，不用new JdbcTemplate了。

package jdbc;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;import org.springframework.jdbc.core.support.JdbcDaoSupport;public class Test extends JdbcDaoSupport {//JdbcDaoSupport類已經有了public final void setDataSource(DataSource dataSource)了//不用重寫也不能重寫public void insert(User u) {String sql = "insert into _user " + "values(null, ?, ?)";//普通的sql語句this.getJdbcTemplate().update(sql, new Object[]{u.getName(), u.getPassword()});}public static void main(String[] args) {ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");Test t = (Test) ctx.getBean("test");User u = new User();u.setName("dd");u.setPassword("dd");t.insert(u);}}

三種方法哪一種更簡單一目瞭然。

我參考的文章：Spring + JdbcTemplate + JdbcDaoSupport Examples