Spring使用c3p0实现数据增删改查

一、导入Spring、c3p0、mysql的jar包

二、配置xml文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
　　 <!-- 实例化c3p0对象 -->
    <bean class="com.mchange.v2.c3p0.ComboPooledDataSource" id="dataSource">
        <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
        <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/mydb?characterEncoding=GBK"></property>
        <property name="user" value="root"></property>
        <property name="password" value=""></property>
        
　　　　 <!--依次为数据库连接池最小连接数、最大连接数、初始连接数-->
        <property name="minPoolSize" value="3"></property>
        <property name="maxPoolSize" value="15"></property>
        <property name="initialPoolSize" value="3"></property>


    </bean>

　　<!-- 配置JDBCTemplate -->
    <bean class="org.springframework.jdbc.core.JdbcTemplate" id="jdbcTemplate">
        <property name="dataSource" ref="dataSource"></property>
    </bean>
</beans>

三、编写代码

Nation类

package maya.entities;

public class Nation {
    private String code;
    private String name;
    public String getCode() {
        return code;
    }
    public void setCode(String code) {
        this.code = code;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
}

Test类

package maya.test;

import java.sql.Connection;
import java.util.ArrayList;
import java.util.List;

import javax.sql.DataSource;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;

import com.mchange.v2.c3p0.ComboPooledDataSource;

import maya.entities.Nation;


public class TestC3P0 {

    //查单行单列
    public static void main(String[] args) {
        ApplicationContext context = new ClassPathXmlApplicationContext("beans.xml");
        DataSource ds = (DataSource)context.getBean("dataSource");
        JdbcTemplate j = (JdbcTemplate)context.getBean("jdbcTemplate");
        //查询
        String sql = "select count(*) from nation";
        long count = j.queryForObject(sql,Long.class);
        System.out.println(count);
    }

    //查全部
    public static void main8(String[] args) {
        ApplicationContext context = new ClassPathXmlApplicationContext("beans.xml");
        DataSource ds = (DataSource)context.getBean("dataSource");
        JdbcTemplate j = (JdbcTemplate)context.getBean("jdbcTemplate");
        //查询
        String sql = "select * from nation";
        RowMapper<Nation> rw = new BeanPropertyRowMapper<Nation>(Nation.class);
        List<Nation> list = j.query(sql, rw);
        for (Nation data : list) {
            System.out.println(data.getName());
        }
    }

    //查单个
    public static void main7(String[] args) {
        ApplicationContext context = new ClassPathXmlApplicationContext("beans.xml");
        DataSource ds = (DataSource)context.getBean("dataSource");
        JdbcTemplate j = (JdbcTemplate)context.getBean("jdbcTemplate");
        //查询
        String sql = "select * from nation where code=?";
        RowMapper<Nation> rm = new BeanPropertyRowMapper<Nation>(Nation.class);
        Nation data = j.queryForObject(sql, rm,"n005");
        System.out.println(data.getName());
    }

    //批量增加
    public static void main6(String[] args) {
        ApplicationContext context = new ClassPathXmlApplicationContext("beans.xml");
        DataSource ds = (DataSource)context.getBean("dataSource");
        JdbcTemplate j = (JdbcTemplate)context.getBean("jdbcTemplate");
        //增加
        String sql = "insert into nation values(?,?) ";
        //使用数组
        List<Object[]> batchArgs = new ArrayList<Object[]>();
        batchArgs.add(new Object[] {"n005","侗族"});
        batchArgs.add(new Object[] {"n006","朝鲜族"});
        j.batchUpdate(sql,batchArgs);
    }

    //删除单个
    public static void main5(String[] args) {
        ApplicationContext context = new ClassPathXmlApplicationContext("beans.xml");
        DataSource ds = (DataSource)context.getBean("dataSource");
        JdbcTemplate j = (JdbcTemplate)context.getBean("jdbcTemplate");
        //删除
        String sql = "delete from nation where code=?";
        j.update(sql,"n005");
    }

    //增加单个
    public static void main4(String[] args) {
        ApplicationContext context = new ClassPathXmlApplicationContext("beans.xml");
        DataSource ds = (DataSource)context.getBean("dataSource");
        JdbcTemplate j = (JdbcTemplate)context.getBean("jdbcTemplate");
        //增加
        String sql = "insert into nation value(?,?)";
        j.update(sql, "n005", "侗族");
    }

    //修改单个
    public static void main3(String[] args) {
        //JdbcTemplate。加载xml文件，创建连接池，建立连接
        ApplicationContext  context = new ClassPathXmlApplicationContext("beans.xml");
        DataSource ds = (DataSource)context.getBean("dataSource");
        JdbcTemplate j = (JdbcTemplate)context.getBean("jdbcTemplate");
        
        //修改
        String sql = "update info set name=? where code=?";
        j.update(sql, "张琳", "p005");//update方法可以执行insert,update,delete
    }
}

还可把sql语句写作用于传递外部参数为语句中变量赋值（:=）的方式

1.配置xml文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
    <bean class="com.mchange.v2.c3p0.ComboPooledDataSource" id="dataSource">
        <property name="driverClass" value="com.mysql.jdbc.Driver"></property>
        <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/mydb?characterEncoding=GBK"></property>
        <property name="user" value="root"></property>
        <property name="password" value=""></property>
        
        <property name="minPoolSize" value="3"></property>
        <property name="maxPoolSize" value="15"></property>
        <property name="initialPoolSize" value="3"></property>
    </bean>
    <!-- 命名的JDBCTemplate -->
    <bean class="org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate" id="namedParameterJdbcTemplate">
　　　　 <!--方法注入-->
        <constructor-arg ref="dataSource"></constructor-arg>
    </bean>
</beans>

2.写代码

方法一：

public static void main(String[] args) {
        ApplicationContext context = new ClassPathXmlApplicationContext("beans.xml");
        DataSource ds = (DataSource)context.getBean("dataSource");
        NamedParameterJdbcTemplate j = (NamedParameterJdbcTemplate)context.getBean("namedParameterJdbcTemplate");
        String sql = "select * from nation where code=:code";
        Map<String, String> paramMap = new HashMap<String,String>();
        paramMap.put("code", "n003");
        RowMapper<Nation> rw = new BeanPropertyRowMapper<Nation>(Nation.class);
        Nation data = j.queryForObject(sql, paramMap, rw);
　　　　 //输出查看结果        
　　　　 System.out.println(data.getName());
    }

方法二：

public static void main(String[] args) throws Exception{
        ComboPooledDataSource ds = new ComboPooledDataSource();
        ds.setDriverClass("com.mysql.jdbc.Driver");
        ds.setJdbcUrl("jdbc:mysql://localhost:3306/mydb?characterEncoding");
        ds.setUser("root");
        ds.setPassword("");
        ds.setMinPoolSize(5);
        ds.setMaxPoolSize(15);
        
        NamedParameterJdbcTemplate j = new NamedParameterJdbcTemplate(ds);
        String sql = "select * from nation where code=:code";
        Map<String, String> paramMap = new HashMap<String,String>();
        paramMap.put("code", "n003");
        RowMapper<Nation> rm = new BeanPropertyRowMapper<Nation>(Nation.class);
        Nation data = j.queryForObject(sql, paramMap, rm);
        System.out.println(data.getName());
    }