（025）Spring Boot之JdbcTemplate与Transactional事务处理

（一）springboot提供了JdbcTemplate类来快捷的实现操作数据库，记录如下：

　　pom.xml

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.edu.spring</groupId>
    <artifactId>springboot_web</artifactId>
    <version>1.0.0</version>

    <name>springboot_web</name>
    <!-- FIXME change it to the project's website -->
    <url>http://www.example.com</url>
    <parent> 
        <groupId>org.springframework.boot</groupId> 
        <artifactId>spring-boot-starter-parent</artifactId> 
        <version>2.0.4.RELEASE</version> 
    </parent>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
    </dependencies>

</project>

　　application.properties

spring.datasource.driverClassName=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://127.0.0.1:3309/springboot
spring.datasource.username=root
spring.datasource.password=123456

　　ProductDao.java

package com.edu.spring.springboot;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;

@Repository
public class ProductDao {

    @Autowired
    private JdbcTemplate jdbcTemplate;
    
    public void add(String name){
        String sql="insert into t_product(pname) values('"+name+"')";
        jdbcTemplate.execute(sql);
    }
    
}

　　App.java

package com.edu.spring.springboot;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;

@SpringBootApplication
public class App    
{ 
    public static void main(String[] args) throws Exception{
        ConfigurableApplicationContext context=SpringApplication.run(App.class, args); 
        context.getBean(ProductDao.class).add("测试1");
        context.close();
    }
} 

　　运行结果如下：

 （二）springboot中使用Transactional注解处理事务（其实是spring中的注解）

　　（1）默认运行时异常才会回滚，否需要rollbackFor指定：如@Transactional(rollbackFor=Exception.class)表示所有异常回滚。

　　App.java

package com.edu.spring.springboot;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;

@SpringBootApplication
public class App    
{ 
    public static void main(String[] args) throws Exception{
        ConfigurableApplicationContext context=SpringApplication.run(App.class, args); 
        context.getBean(ProductDao.class).addBitch("测试1","测试2","测试3","测试4");
        context.close();
    }
} 

　　1、测试不加注解的情况：

package com.edu.spring.springboot;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;

@Repository
public class ProductDao {

    @Autowired
    private JdbcTemplate jdbcTemplate;
    
    public void addBitch(String... names) throws Exception{
        for(String name:names){
            String sql="insert into t_product(pname) values('"+name+"')";
            jdbcTemplate.execute(sql);
            if("".equals("")){
                throw new NullPointerException();
            }
        }
    }
    
}

　　运行结果，没有回滚，如下：

　　2、测试添加默认注解，抛出运行时异常的情况：

package com.edu.spring.springboot;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;

@Repository
public class ProductDao {

    @Autowired
    private JdbcTemplate jdbcTemplate;
    
    @Transactional
    public void addBitch(String... names) throws Exception{
        for(String name:names){
            String sql="insert into t_product(pname) values('"+name+"')";
            jdbcTemplate.execute(sql);
            if("".equals("")){
                throw new NullPointerException();
            }
        }
    }
    
}

　　运行结果，回滚，如下：

 　　3、测试添加默认注解，抛出检查异常的情况：

package com.edu.spring.springboot;

import java.io.FileNotFoundException;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;

@Repository
public class ProductDao {

    @Autowired
    private JdbcTemplate jdbcTemplate;
    
    @Transactional
    public void addBitch(String... names) throws Exception{
        for(String name:names){
            String sql="insert into t_product(pname) values('"+name+"')";
            jdbcTemplate.execute(sql);
            if("".equals("")){
                throw new FileNotFoundException();
            }
        }
    }
    
}

　　运行结果，没有回滚，如下：

 　　4、测试添加rollbackFor的注解，抛出指定异常的情况：

package com.edu.spring.springboot;

import java.io.FileNotFoundException;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;

@Repository
public class ProductDao {

    @Autowired
    private JdbcTemplate jdbcTemplate;
    
    @Transactional(rollbackFor=Exception.class)
    public void addBitch(String... names) throws Exception{
        for(String name:names){
            String sql="insert into t_product(pname) values('"+name+"')";
            jdbcTemplate.execute(sql);
            if("".equals("")){
                throw new FileNotFoundException();
            }
        }
    }
    
}

　　运行结果，回滚，如下：

　　（2）Transactional注解加在直接调用的方法上面才可以，否则不会回滚

　　1、下面的代码会回滚

package com.edu.spring.springboot;

import java.io.FileNotFoundException;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;

@Repository
public class ProductDao {

    @Autowired
    private JdbcTemplate jdbcTemplate;
    
    @Transactional(rollbackFor=Exception.class)
    public void addBitch(String... names) throws Exception{
        actiontest(names);
    }
    
    private void actiontest(String...names) throws Exception{
        for(String name:names){
            String sql="insert into t_product(pname) values('"+name+"')";
            jdbcTemplate.execute(sql);
            if("".equals("")){
                throw new FileNotFoundException();
            }
        }
    }
    
}

　　下面的代码不会回滚

package com.edu.spring.springboot;

import java.io.FileNotFoundException;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;

@Repository
public class ProductDao {

    @Autowired
    private JdbcTemplate jdbcTemplate;
    
    public void addBitch(String... names) throws Exception{
        actiontest(names);
    }
    
    @Transactional(rollbackFor=Exception.class)
    private void actiontest(String...names) throws Exception{
        for(String name:names){
            String sql="insert into t_product(pname) values('"+name+"')";
            jdbcTemplate.execute(sql);
            if("".equals("")){
                throw new FileNotFoundException();
            }
        }
    }
    
}