spring中提供了一个可以操作数据库的对象，对象封装了jdbc技术，与DBUtils中的QueryRunner非常相似，JDBCTemplateJDBC模板对象

准备工作

导包：

4+2
spring-test、spring-aop、
c3p0连接池、JDBC驱动
spring-jdbc、spring-tx事务

准备数据库

测试：

package cn.lc.a_jdbctemplate;
import org.junit.Test;
import org.springframework.jdbc.core.JdbcTemplate;
import com.mchange.v2.c3p0.ComboPooledDataSource;
//演示jdbc模板
public class Demo { 
    @Test   
    public void fun1() throws Exception{
        
        //1准备连接池        
        ComboPooledDataSource dataSource = new ComboPooledDataSource();
        dataSource.setDriverClass("com.mysql.jdbc.Driver");
        dataSource.setJdbcUrl("jdbc:mysql:///hibernate");
        dataSource.setUser("root");
        dataSource.setPassword("");
            
        //2创建jdbc模板对象   
        JdbcTemplate jt = new JdbcTemplate();
        jt.setDataSource(dataSource);   
        //2.书写sql，并执行
        String sql = "insert into t_user values(1,'rose')";
        jt.update(sql); 
    }
}

写入数据库.png

spring整合JDBC*连接池&JDBC模板&Dao配置到spring容器

jdbc实现增删改查

//使用jdbc实现增删改查
public class UserDaoImpl implements UserDao {
    
    private JdbcTemplate jt;
    @Override
    public void save(User u) {
        String sql = "insert into t_user values(null,?)";

        jt.update(sql, u.getName());
    }

    @Override
    public void delete(Integer id) {
        String sql = "delete from t_user where id = ?";

        jt.update(sql, id);

    }

    @Override
    public void update(User u) {
        String sql =" update t_user set name = ? where id = ?";

        jt.update(sql, u.getName(),u.getId());
    }

    @Override
    public User getById(Integer id){
        
        String sql =" select * from t_user where id = ?";

        return jt.queryForObject(sql, new RowMapper<User>(){

            @Override
            public User mapRow(ResultSet rs, int arg1) throws SQLException {
                    User u = new User();
                    u.setId(rs.getInt("id"));
                    u.setName(rs.getString("name"));                
                    return u;
            }},id);
        }

    @Override
    public int getTotalCount() {
        String sql =" select count(*) from t_user ";
        
        Integer queryForObject = jt.queryForObject(sql, Integer.class);
        
        return queryForObject;
    }

    @Override
    public List<User> getAll() {
        String sql =" select * from t_user ";
        
        List<User> list =   jt.query(sql, new RowMapper<User>(){            
            @Override
            public User mapRow(ResultSet rs, int arg1) throws SQLException {
                User u = new User();
                u.setId(rs.getInt("id"));
                u.setName(rs.getString("name"));                
                return u;
            }});
        return list;
    }

    public void setJt(JdbcTemplate jt) {
        this.jt = jt;
    }

配置applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd ">

<!-- 1.将连接池放入spring容器 -->
<bean name="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
    <property name="jdbcUrl" value="jdbc:mysql:///hibernate"></property>
    <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
    <property name="user" value="root"></property>
    <property name="password" value=""></property>
</bean>
<!-- 2.将JDBCTemplate放入spring容器 -->
<bean name="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
    <property name="dataSource" ref="dataSource"></property>
</bean>
<!-- 3.将UserDao放入spring容器 -->
<bean name="userDao" class="cn.lc.a_jdbctemplate.UserDaoImpl">
    <property name="jt" ref="jdbcTemplate"></property>
</bean> 
</beans>

测试

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class Demo {
    @Resource(name="userDao")
    private UserDao ud;
  @Test
    public void fun2() throws Exception{
        User u = new User();
        u.setName("tom");
        ud.save(u);

    }
    @Test
    public void fun3() throws Exception{
        User u = new User();
        
        u.setId(2);
        u.setName("shangsan");
        ud.update(u);

    }

//结果成功

结果.png

spring整合jdbc读取properties配置

配置db.properties文件

//spring读取文件最好加一个前缀
jdbc.jdbcUrl=jdbc:mysql:///hibernate
jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.user=root
jdbc.password=

配置applicationContext.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.2.xsd ">

<!-- 指定spring读取db.properties文件 -->
<context:property-placeholder location="classpath:db.properties"/>

<!-- 1.将连接池放入spring容器 -->
<bean name="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
    <property name="jdbcUrl" value="${jdbc.jdbcUrl}"></property>
    <property name="driverClass" value="${jdbc.driverClass}"></property>
    <property name="user" value="${jdbc.user}"></property>
    <property name="password" value="${jdbc.password}"></property>
</bean>
<!-- 2.将JDBCTemplate放入spring容器 -->
<bean name="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
    <property name="dataSource" ref="dataSource"></property>
</bean>
<!-- 3.将UserDao放入spring容器 -->
<bean name="userDao" class="cn.lc.a_jdbctemplate.UserDaoImpl">
    <property name="jt" ref="jdbcTemplate"></property>
</bean> 
</beans>