推荐几个并发工具类
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本项目使用的环境：
- 开发工具：Intellij IDEA 2017.1.3
- springboot: 1.5.6
- jdk：1.8.0_161
- maven:3.3.9
额外功能
- PageHelper 分页插件
- mybatis generator 自动生成代码插件
步骤：
1. 创建一个springboot项目：
2. 创建项目的文件结构以及jdk的版本
3. 选择项目所需要的依赖
然后点击finish
4. 看一下文件的结构：
5. 查看一下pom.xml：
1 <?xml version="1.0" encoding="UTF-8"?> 2 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 3 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> 4 <modelVersion>4.0.0</modelVersion> 5 6 <groupId>com.winter</groupId> 7 <artifactId>springboot-mybatis-demo</artifactId> 8 <version>0.0.1-SNAPSHOT</version> 9 <packaging>jar</packaging> 10 11 <name>springboot-mybatis-demo</name> 12 <description>Demo project for Spring Boot</description> 13 14 <parent> 15 <groupId>org.springframework.boot</groupId> 16 <artifactId>spring-boot-starter-parent</artifactId> 17 <version>1.5.6.RELEASE</version> 18 <relativePath/> <!-- lookup parent from repository --> 19 </parent> 20 21 <properties> 22 <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> 23 <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> 24 <java.version>1.7</java.version> 25 </properties> 26 27 <dependencies> 28 <dependency> 29 <groupId>org.mybatis.spring.boot</groupId> 30 <artifactId>mybatis-spring-boot-starter</artifactId> 31 <version>1.3.0</version> 32 </dependency> 33 <dependency> 34 <groupId>org.springframework.boot</groupId> 35 <artifactId>spring-boot-starter-thymeleaf</artifactId> 36 </dependency> 37 <dependency> 38 <groupId>org.springframework.boot</groupId> 39 <artifactId>spring-boot-starter-web</artifactId> 40 </dependency> 41 42 <dependency> 43 <groupId>org.springframework.boot</groupId> 44 <artifactId>spring-boot-starter-test</artifactId> 45 <scope>test</scope> 46 </dependency> 47 <dependency> 48 <groupId>mysql</groupId> 49 <artifactId>mysql-connector-java</artifactId> 50 <version>5.1.35</version> 51 </dependency> 52 53 54 <dependency> 55 <groupId>com.fasterxml.jackson.core</groupId> 56 <artifactId>jackson-core</artifactId> 57 </dependency> 58 <dependency> 59 <groupId>com.fasterxml.jackson.core</groupId> 60 <artifactId>jackson-databind</artifactId> 61 </dependency> 62 <dependency> 63 <groupId>com.fasterxml.jackson.datatype</groupId> 64 <artifactId>jackson-datatype-joda</artifactId> 65 </dependency> 66 <dependency> 67 <groupId>com.fasterxml.jackson.module</groupId> 68 <artifactId>jackson-module-parameter-names</artifactId> 69 </dependency> 70 <!-- 分页插件 --> 71 <dependency> 72 <groupId>com.github.pagehelper</groupId> 73 <artifactId>pagehelper-spring-boot-starter</artifactId> 74 <version>1.1.2</version> 75 </dependency> 76 <!-- alibaba的druid数据库连接池 --> 77 <dependency> 78 <groupId>com.alibaba</groupId> 79 <artifactId>druid-spring-boot-starter</artifactId> 80 <version>1.1.0</version> 81 </dependency> 82 </dependencies> 83 84 <build> 85 <plugins> 86 <plugin> 87 <groupId>org.springframework.boot</groupId> 88 <artifactId>spring-boot-maven-plugin</artifactId> 89 </plugin> 90 <!-- mybatis generator 自动生成代码插件 --> 91 <plugin> 92 <groupId>org.mybatis.generator</groupId> 93 <artifactId>mybatis-generator-maven-plugin</artifactId> 94 <version>1.3.2</version> 95 <configuration> 96 <configurationFile>${basedir}/src/main/resources/generator/generatorConfig.xml</configurationFile> 97 <overwrite>true</overwrite> 98 <verbose>true</verbose> 99 </configuration> 100 </plugin> 101 </plugins> 102 </build> 103 104 105 </project>
6. 项目不使用application.properties文件 而使用更加简洁的application.yml文件：
将原有的resource文件夹下的application.properties文件删除，创建一个新的application.yml配置文件，
文件的内容如下：
1 server: 2 port: 8080 3 4 spring: 5 datasource: 6 name: test 7 url: jdbc:mysql://127.0.0.1:3306/depot 8 username: root 9 password: root 10 # 使用druid数据源 11 type: com.alibaba.druid.pool.DruidDataSource 12 driver-class-name: com.mysql.jdbc.Driver 13 filters: stat 14 maxActive: 20 15 initialSize: 1 16 maxWait: 60000 17 minIdle: 1 18 timeBetweenEvictionRunsMillis: 60000 19 minEvictableIdleTimeMillis: 300000 20 validationQuery: select ‘x‘ 21 testWhileIdle: true 22 testOnBorrow: false 23 testOnReturn: false 24 poolPreparedStatements: true 25 maxOpenPreparedStatements: 20 26 27 ## 该配置节点为独立的节点，有很多同学容易将这个配置放在spring的节点下，导致配置无法被识别 28 mybatis: 29 mapper-locations: classpath:mapping/*.xml #注意：一定要对应mapper映射xml文件的所在路径 30 type-aliases-package: com.winter.model # 注意：对应实体类的路径 31 32 #pagehelper分页插件 33 pagehelper: 34 helperDialect: mysql 35 reasonable: true 36 supportMethodsArguments: true 37 params: count=countSql
7. 创建数据库：
1 CREATE DATABASE mytest; 2 3 CREATE TABLE t_user( 4 user_id INT NOT NULL PRIMARY KEY AUTO_INCREMENT, 5 user_name VARCHAR(255) NOT NULL , 6 password VARCHAR(255) NOT NULL , 7 phone VARCHAR(255) NOT NULL 8 ) ENGINE=INNODB AUTO_INCREMENT=1000 DEFAULT CHARSET=utf8;
8. 使用mybatis generator 自动生成代码：
- 配置pom.xml中generator 插件所对应的配置文件 ${basedir}/src/main/resources/generator/generatorConfig.xml
1 <?xml version="1.0" encoding="UTF-8"?> 2 <!DOCTYPE generatorConfiguration 3 PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN" 4 "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd"> 5 <generatorConfiguration> 6 <!-- 数据库驱动:选择你的本地硬盘上面的数据库驱动包--> 7 <classPathEntry location="E:developermybatis-generator-core-1.3.2libmysql-connector-java-5.1.25-bin.jar"/> 8 <context id="DB2Tables" targetRuntime="MyBatis3"> 9 <commentGenerator> 10 <property name="suppressDate" value="true"/> 11 <!-- 是否去除自动生成的注释 true：是 ： false:否 --> 12 <property name="suppressAllComments" value="true"/> 13 </commentGenerator> 14 <!--数据库链接URL，用户名、密码 --> 15 <jdbcConnection driverClass="com.mysql.jdbc.Driver" connectionURL="jdbc:mysql://127.0.0.1/mytest" userId="root" password="root"> 16 </jdbcConnection> 17 <javaTypeResolver> 18 <property name="forceBigDecimals" value="false"/> 19 </javaTypeResolver> 20 <!-- 生成模型的包名和位置--> 21 <javaModelGenerator targetPackage="com.winter.model" targetProject="src/main/java"> 22 <property name="enableSubPackages" value="true"/> 23 <property name="trimStrings" value="true"/> 24 </javaModelGenerator> 25 <!-- 生成映射文件的包名和位置--> 26 <sqlMapGenerator targetPackage="mapping" targetProject="src/main/resources"> 27 <property name="enableSubPackages" value="true"/> 28 </sqlMapGenerator> 29 <!-- 生成DAO的包名和位置--> 30 <javaClientGenerator type="XMLMAPPER" targetPackage="com.winter.mapper" targetProject="src/main/java"> 31 <property name="enableSubPackages" value="true"/> 32 </javaClientGenerator> 33 <!-- 要生成的表 tableName是数据库中的表名或视图名 domainObjectName是实体类名--> 34 <table tableName="t_user" domainObjectName="User" enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false" enableSelectByExample="false" selectByExampleQueryId="false"></table> 35 </context> 36 </generatorConfiguration>
- 点击run-Edit Configurations
- 添加配置
-
运行
注意！！！同一张表一定不要运行多次，因为mapper的映射文件中会生成多次的代码，导致报错，切记
最后生成的文件以及结构：
9. 生成的文件
UserMapper.java
1 package com.winter.mapper; 2 3 import com.winter.model.User; 4 5 public interface UserMapper { 6 int deleteByPrimaryKey(Integer userId); 7 8 int insert(User record); 9 10 int insertSelective(User record); 11 12 User selectByPrimaryKey(Integer userId); 13 14 int updateByPrimaryKeySelective(User record); 15 16 int updateByPrimaryKey(User record); 17 //这个方式我自己加的 18 List<User> selectAllUser(); 19 }
User.java
1 package com.winter.model; 2 3 public class User { 4 private Integer userId; 5 6 private String userName; 7 8 private String password; 9 10 private String phone; 11 12 public Integer getUserId() { 13 return userId; 14 } 15 16 public void setUserId(Integer userId) { 17 this.userId = userId; 18 } 19 20 public String getUserName() { 21 return userName; 22 } 23 24 public void setUserName(String userName) { 25 this.userName = userName == null ? null : userName.trim(); 26 } 27 28 public String getPassword() { 29 return password; 30 } 31 32 public void setPassword(String password) { 33 this.password = password == null ? null : password.trim(); 34 } 35 36 public String getPhone() { 37 return phone; 38 } 39 40 public void setPhone(String phone) { 41 this.phone = phone == null ? null : phone.trim(); 42 } 43 }
对于sql语句这种黄色的背景，真心是看不下去了（解决方案）：
**UserMapper.xml **
1 <?xml version="1.0" encoding="UTF-8" ?> 2 <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" > 3 <mapper namespace="com.winter.mapper.UserMapper" > 4 <resultMap id="BaseResultMap" type="com.winter.model.User" > 5 <id column="user_id" property="userId" jdbcType="INTEGER" /> 6 <result column="user_name" property="userName" jdbcType="VARCHAR" /> 7 <result column="password" property="password" jdbcType="VARCHAR" /> 8 <result column="phone" property="phone" jdbcType="VARCHAR" /> 9 </resultMap> 10 <sql id="Base_Column_List" > 11 user_id, user_name, password, phone 12 </sql> 13 <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Integer" > 14 select 15 <include refid="Base_Column_List" /> 16 from t_user 17 where user_id = #{userId,jdbcType=INTEGER} 18 </select> 19 <!-- 这个方法是我自己加的 --> 20 <select id="selectAllUser" resultMap="BaseResultMap"> 21 select 22 <include refid="Base_Column_List" /> 23 from t_user 24 </select> 25 <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer" > 26 delete from t_user 27 where user_id = #{userId,jdbcType=INTEGER} 28 </delete> 29 <insert id="insert" parameterType="com.winter.model.User" > 30 insert into t_user (user_id, user_name, password, 31 phone) 32 values (#{userId,jdbcType=INTEGER}, #{userName,jdbcType=VARCHAR}, #{password,jdbcType=VARCHAR}, 33 #{phone,jdbcType=VARCHAR}) 34 </insert> 35 <insert id="insertSelective" parameterType="com.winter.model.User" > 36 insert into t_user 37 <trim prefix="(" suffix=")" suffixOverrides="," > 38 <if test="userId != null" > 39 user_id, 40 </if> 41 <if test="userName != null" > 42 user_name, 43 </if> 44 <if test="password != null" > 45 password, 46 </if> 47 <if test="phone != null" > 48 phone, 49 </if> 50 </trim> 51 <trim prefix="values (" suffix=")" suffixOverrides="," > 52 <if test="userId != null" > 53 #{userId,jdbcType=INTEGER}, 54 </if> 55 <if test="userName != null" > 56 #{userName,jdbcType=VARCHAR}, 57 </if> 58 <if test="password != null" > 59 #{password,jdbcType=VARCHAR}, 60 </if> 61 <if test="phone != null" > 62 #{phone,jdbcType=VARCHAR}, 63 </if> 64 </trim> 65 </insert> 66 <update id="updateByPrimaryKeySelective" parameterType="com.winter.model.User" > 67 update t_user 68 <set > 69 <if test="userName != null" > 70 user_name = #{userName,jdbcType=VARCHAR}, 71 </if> 72 <if test="password != null" > 73 password = #{password,jdbcType=VARCHAR}, 74 </if> 75 <if test="phone != null" > 76 phone = #{phone,jdbcType=VARCHAR}, 77 </if> 78 </set> 79 where user_id = #{userId,jdbcType=INTEGER} 80 </update> 81 <update id="updateByPrimaryKey" parameterType="com.winter.model.User" > 82 update t_user 83 set user_name = #{userName,jdbcType=VARCHAR}, 84 password = #{password,jdbcType=VARCHAR}, 85 phone = #{phone,jdbcType=VARCHAR} 86 where user_id = #{userId,jdbcType=INTEGER} 87 </update> 88 </mapper>
10. 打开类SpringbootMybatisDemoApplication.java，这个是springboot的启动类。我们需要添加点东西：
1 package com.winter; 2 3 import org.mybatis.spring.annotation.MapperScan; 4 import org.springframework.boot.SpringApplication; 5 import org.springframework.boot.autoconfigure.SpringBootApplication; 6 7 @SpringBootApplication 8 @MapperScan("com.winter.mapper")//将项目中对应的mapper类的路径加进来就可以了 9 public class SpringbootMybatisDemoApplication { 10 11 public static void main(String[] args) { 12 SpringApplication.run(SpringbootMybatisDemoApplication.class, args); 13 } 14 }
注意：@MapperScan("com.winter.mapper")这个注解非常的关键，这个对应了项目中mapper（dao）所对应的包路径，很多同学就是这里忘了加导致异常的
11. 到这里所有的搭建工作都完成了，接下来就是测试的工作，没使用junit4进行测试：
首先看一下完成之后的文件的结构：
现在controller，service层的代码都写好：
UserController.java
1 package com.winter.Controller; 2 3 import com.winter.model.User; 4 import com.winter.service.UserService; 5 import org.springframework.beans.factory.annotation.Autowired; 6 import org.springframework.stereotype.Controller; 7 import org.springframework.web.bind.annotation.PathVariable; 8 import org.springframework.web.bind.annotation.RequestMapping; 9 import org.springframework.web.bind.annotation.ResponseBody; 10 11 /** 12 * Created by Administrator on 2017/8/16. 13 */ 14 @Controller 15 @RequestMapping(value = "/user") 16 public class UserController { 17 18 @Autowired 19 private UserService userService; 20 21 @ResponseBody 22 @RequestMapping(value = "/add", produces = {"application/json;charset=UTF-8"}) 23 public int addUser(User user){ 24 return userService.addUser(user); 25 } 26 27 @ResponseBody 28 @RequestMapping(value = "/all/{pageNum}/{pageSize}", produces = {"application/json;charset=UTF-8"}) 29 public Object findAllUser(@PathVariable("pageNum") int pageNum, @PathVariable("pageSize") int pageSize){ 30 31 return userService.findAllUser(pageNum,pageSize); 32 } 33 }
UserService.java
1 package com.winter.service; 2 3 import com.winter.model.User; 4 5 import java.util.List; 6 7 /** 8 * Created by Administrator on 2017/8/16. 9 */ 10 public interface UserService { 11 12 int addUser(User user); 13 14 List<User> findAllUser(int pageNum, int pageSize); 15 }
UserServiceImpl.java
1 package com.winter.service.impl; 2 3 import com.github.pagehelper.PageHelper; 4 import com.winter.mapper.UserMapper; 5 import com.winter.model.User; 6 import com.winter.service.UserService; 7 import org.springframework.beans.factory.annotation.Autowired; 8 import org.springframework.stereotype.Service; 9 10 import java.util.List; 11 12 /** 13 * Created by Administrator on 2017/8/16. 14 */ 15 @Service(value = "userService") 16 public class UserServiceImpl implements UserService { 17 18 @Autowired 19 private UserMapper userMapper;//这里会报错，但是并不会影响 20 21 @Override 22 public int addUser(User user) { 23 24 return userMapper.insertSelective(user); 25 } 26 27 /* 28 * 这个方法中用到了我们开头配置依赖的分页插件pagehelper 29 * 很简单，只需要在service层传入参数，然后将参数传递给一个插件的一个静态方法即可； 30 * pageNum 开始页数 31 * pageSize 每页显示的数据条数 32 * */ 33 @Override 34 public List<User> findAllUser(int pageNum, int pageSize) { 35 //将参数传给这个方法就可以实现物理分页了，非常简单。 36 PageHelper.startPage(pageNum, pageSize); 37 return userMapper.selectAllUser(); 38 } 39 }
如果强迫症看不下去那个报错：（解决方法）
测试我使用了idea一个很用心的功能。
可以发http请求的插件：
点击左侧的运行按钮就可以发送请求了；
如果返回值正确 说明你已经搭建成功了！！
ps：如果出现mapper注入不了的情况，请检查版本，当前博客的搭建方法只适合1.5.*版本的。
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