Spring与C3p0连接数据库对事务操作

maven包：

 <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <maven.compiler.source>1.7</maven.compiler.source>
     <maven.compiler.target>1.7</maven.compiler.target>
     <spring.version>4.3.24.RELEASE</spring.version>
   </properties>

   <dependencies>
     <dependency>
       <groupId>junit</groupId>
       <artifactId>junit</artifactId>
       <version>4.11</version>
       <scope>test</scope>
     </dependency>
     <!-- Spring -->
     <dependency>
       <groupId>org.springframework</groupId>
       <artifactId>spring-core</artifactId>
       <version>${spring.version}</version>
     </dependency>
     <dependency>
       <groupId>org.springframework</groupId>
       <artifactId>spring-context</artifactId>
       <version>${spring.version}</version>
     </dependency>
     <dependency>
       <groupId>org.springframework</groupId>
       <artifactId>spring-web</artifactId>
       <version>${spring.version}</version>
     </dependency>
     <dependency>
       <groupId>org.springframework</groupId>
       <artifactId>spring-context-support</artifactId>
       <version>${spring.version}</version>
     </dependency>
     <dependency>
       <groupId>org.springframework</groupId>
       <artifactId>spring-webmvc</artifactId>
       <version>${spring.version}</version>
     </dependency>
     <dependency>
       <groupId>org.springframework</groupId>
       <artifactId>spring-test</artifactId>
       <version>${spring.version}</version>
     </dependency>
     <!-- aop -->
     <dependency>
       <groupId>org.springframework</groupId>
       <artifactId>spring-aop</artifactId>
       <version>${spring.version}</version>
     </dependency>
     <dependency>
       <groupId>org.aspectj</groupId>
       <artifactId>aspectjweaver</artifactId>
       <version>1.8.13</version>
     </dependency>
     <dependency>
       <groupId>cglib</groupId>
       <artifactId>cglib</artifactId>
       <version>3.2.4</version>
     </dependency>
     <!-- spring jdbc -->
     <dependency>
       <groupId>mysql</groupId>
       <artifactId>mysql-connector-java</artifactId>
       <version>5.1.47</version>
     </dependency>
     <dependency>
       <groupId>org.springframework</groupId>
       <artifactId>spring-jdbc</artifactId>
       <version>${spring.version}</version>
     </dependency>
     <dependency>
       <groupId>org.springframework</groupId>
       <artifactId>spring-tx</artifactId>
       <version>${spring.version}</version>
     </dependency>
     <!-- C3p0-->
     <dependency>
       <groupId>com.mchange</groupId>
       <artifactId>c3p0</artifactId>
       <version>0.9.5.4</version>
     </dependency>
   </dependencies>

applicationContext.xml：

C3p0连接配置：

 <?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:tx="http://www.springframework.org/schema/tx"
        xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/aop https://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd">

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

     <bean id="userDao" class="com.etc.dao.UserDAO">
         <property name="jdbcTemplate" ref="jdbcTemplate"></property>
     </bean>

     <bean id="bankDao" class="com.etc.dao.BankDao">
         <property name="jdbcTemplate" ref="jdbcTemplate"></property>
     </bean>

     <bean id="bankServiceImpl" class="com.etc.service.serviceImpl.BankServiceImpl">
         <property name="bankDao" ref="bankDao"></property>
     </bean>

     <!--基于数据源的事务管理器，通过属性引用数据源-->
     <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
         <property name="dataSource" ref="dataSource"></property>
     </bean>
     <aop:config>
         <aop:pointcut expression="execution(* com.etc.service.*.*(..))" id="pc"/>
         <aop:advisor advice-ref="txAdvice" pointcut-ref="pc"/>
     </aop:config>

     <tx:advice id="txAdvice" transaction-manager="transactionManager">
         <tx:attributes>
             <tx:method name="*"/>
         </tx:attributes>
     </tx:advice>

     <!-- 配置数据源 -->
     <bean id="dataSource"
           class="com.mchange.v2.c3p0.ComboPooledDataSource"
           destroy-method="close">
         <property name="driverClass">
             <value>com.mysql.jdbc.Driver</value>
         </property>
         <property name="jdbcUrl">
             <value>jdbc:mysql://localhost:3310/day07?characterEncoding=UTF-8</value>
         </property>
         <property name="user">
             <value>root</value>
         </property>
         <property name="password">
             <value>123456</value>
         </property>

         <!--连接池中保留的最小连接数。-->
         <property name="minPoolSize">
             <value>5</value>
         </property>

         <!--连接池中保留的最大连接数。Default: 15 -->
         <property name="maxPoolSize">
             <value>30</value>
         </property>

         <!--初始化时获取的连接数，取值应在minPoolSize与maxPoolSize之间。Default: 3 -->
         <property name="initialPoolSize">
             <value>10</value>
         </property>

         <!--最大空闲时间,60秒内未使用则连接被丢弃。若为0则永不丢弃。Default: 0 -->
         <property name="maxIdleTime">
             <value>60</value>
         </property>

         <!--当连接池中的连接耗尽的时候c3p0一次同时获取的连接数。Default: 3 -->
         <property name="acquireIncrement">
             <value>5</value>
         </property>

         <!--JDBC的标准参数，用以控制数据源内加载的PreparedStatements数量。但由于预缓存的statements
          属于单个connection而不是整个连接池。所以设置这个参数需要考虑到多方面的因素。
          如果maxStatements与maxStatementsPerConnection均为0，则缓存被关闭。Default: 0-->
         <property name="maxStatements">
             <value>0</value>
         </property>

         <!--每60秒检查所有连接池中的空闲连接。Default: 0 -->
         <property name="idleConnectionTestPeriod">
             <value>60</value>
         </property>

         <!--定义在从数据库获取新连接失败后重复尝试的次数。Default: 30 -->
         <property name="acquireRetryAttempts">
             <value>30</value>
         </property>

         <!--获取连接失败将会引起所有等待连接池来获取连接的线程抛出异常。但是数据源仍有效
          保留，并在下次调用getConnection()的时候继续尝试获取连接。如果设为true，那么在尝试
          获取连接失败后该数据源将申明已断开并永久关闭。Default: false-->
         <property name="breakAfterAcquireFailure">
             <value>true</value>
         </property>

         <!--因性能消耗大请只在需要的时候使用它。如果设为true那么在每个connection提交的
          时候都将校验其有效性。建议使用idleConnectionTestPeriod或automaticTestTable
          等方法来提升连接测试的性能。Default: false -->
         <property name="testConnectionOnCheckout">
             <value>false</value>
         </property>
     </bean>
 </beans>

userDao

 package com.etc.dao;

 import com.etc.entity.User;
 import org.springframework.jdbc.core.JdbcTemplate;
 import org.springframework.jdbc.core.RowMapper;

 import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.util.List;

 public class UserDAO {

     private JdbcTemplate jdbcTemplate;

     public void save() {
         jdbcTemplate.execute("insert into t_user (username,password) values ('3','4')");
     }

     public List<User> queryAll() {
         return jdbcTemplate.query("select * from t_user", new RowMapper<User>() {
             @Override
             public User mapRow(ResultSet resultSet, int i) throws SQLException {
                 return result(resultSet);
             }
         });
     }

     public User query(User user) {
         return jdbcTemplate.queryForObject("select * from t_user where id=?", new Object[]{user.getId()}, new RowMapper<User>() {
             @Override
             public User mapRow(ResultSet resultSet, int i) throws SQLException {
                 return result(resultSet);
             }
         });
     }

     public static User result(ResultSet resultSet) throws SQLException {
         User user = new User();
         user.setId(resultSet.getInt("id"));
         user.setUsername(resultSet.getString("username"));
         user.setPassword(resultSet.getString("password"));
         return user;
     }

     public JdbcTemplate getJdbcTemplate() {
         return jdbcTemplate;
     }

     public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
         this.jdbcTemplate = jdbcTemplate;
     }
 }