Springboot整合（2）——MyBatis整合

1. 配置

1. 1 在pom文件中添加依赖

        <!-- mysql 驱动-->

        <dependency>

            <groupId>mysql</groupId>

            <artifactId>mysql-connector-java</artifactId>

        </dependency>

       

        <!-- Mybatis 包-->

        <dependency>

            <groupId>org.mybatis.spring.boot</groupId>

            <artifactId>mybatis-spring-boot-starter</artifactId>

            <version>1.3.1</version>

        </dependency>

 

        <!-- Mybatis代码自动生成-->

        <dependency>

            <groupId>org.mybatis.generator</groupId>

            <artifactId>mybatis-generator-core</artifactId>

            <version>1.3.2</version>

        </dependency>

 

1.2 在application.yml文件中增加数据库和mybatis的配置

spring:

  datasource:

    url: jdbc:mysql://localhost:3306/knowledgeisland?useUnicode=true&characterEncoding=UTF-8&autoReconnect=true&allowMultiQueries=true

    username: root

    password: root

    driver-class-name: com.mysql.jdbc.Driver

 

mybatis:

  ##配置mapper.xml扫描路径

  mapper-locations: classpath:mapper/*Mapper.xml,classpath:mapper/auto/*Mapper.xml

  ##配置实体类所在的包

  type-aliases-package: tect.luoyu.ki.entity

 

1.3 在启动类Application里配置mapper接口的扫描路径

@MapperScan("tech.luoyu.ki.mapper")

 

2. 使用mybatis-generator生成代码

mybatis官方提供的代码生成工具可以为我们自动生成entity，mapper接口类以及mapper.xml。 本节将使用基类产生相应的代码。

 

2.1  创建表并插入一条数据

CREATE TABLE `sys_user` (

  `id` varchar(36) NOT NULL COMMENT '主键uuid',

  `userName` varchar(30) NOT NULL COMMENT '用户名',

  `mobilephone` varchar(11) DEFAULT NULL COMMENT '联系电话',

  `loginName` varchar(30) NOT NULL COMMENT '登录账号',

  `loginPassword` varchar(50) NOT NULL COMMENT '登录密码',

  `creater` varchar(36) NOT NULL COMMENT '创建人',

  `createTime` datetime NOT NULL,

  `updater` varchar(36) NOT NULL COMMENT '更新人',

  `updateTime` datetime NOT NULL,

  `dataStatus` tinyint(4) NOT NULL,

  PRIMARY KEY (`id`)

) ENGINE=InnoDB DEFAULT CHARSET=utf8;

 

INSERT INTO `sys_user` VALUES ('1', '风木羽', '18666666666', 'admin', 'admin', '1', '2018-01-01 10:52:00', '1', '2018-01-01 10:52:00', '1');

 

 

 

2.2 创建基类，基类包含以下6个基本属性（具体情况按需）。

    private String id;

    private String creater;

    private Date createTime;

    private String updater;

    private Date updateTime;

    private Byte dataStatus;

    ...getter,setter,toString,equals,hashCode...

注：创建基类的目的在于可以为所有的entity对象添加一些通用方法，如preInsert（插入前做预插入工作：生成ID，设置creater，设置createTime），preUpdate（更新前做预更新工作：生成ID，设置updater，设置updateTime）

    publicvoid preInsert() {

        setId(UUID.randomUUID().toString());

        this.updater = "1";

        this.creater = "1";

        this.updateTime = new Date();

        this.createTime = this.updateTime;

        bytedataStatus = 1;

        setDataStatus(dataStatus);

    }

 

    publicvoid preUpdate() {

        this.updater = "1";

        this.updateTime = new Date();

    }

 

2.3 创建generatorConfig.xml

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

<!DOCTYPE generatorConfiguration

  PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"

  "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd">

 

<generatorConfiguration>

 

  <!-- 指定生成一组对象的环境 -->

  <context id="mysql" targetRuntime="MyBatis3">

    <!-- 自动识别数据库关键字，默认false，如果设置为true，根据SqlReservedWords中定义的关键字列表；

        一般保留默认值，遇到数据库关键字（Java关键字），使用columnOverride覆盖

     -->

    <property name="autoDelimitKeywords" value="false"/>

    <!-- 生成的Java文件的编码 -->

    <property name="javaFileEncoding" value="UTF-8"/>

    <!-- 格式化java代码 -->

    <property name="javaFormatter" value="org.mybatis.generator.api.dom.DefaultJavaFormatter"/>

    <!-- 格式化XML代码 -->

    <property name="xmlFormatter" value="org.mybatis.generator.api.dom.DefaultXmlFormatter"/>

 

    <!-- beginningDelimiter和endingDelimiter：指明数据库的用于标记数据库对象名的符号，比如ORACLE就是双引号，MYSQL默认是`反引号； -->

    <property name="beginningDelimiter" value="`"/>

    <property name="endingDelimiter" value="`"/>

    <!-- 这个plugin是手写的一个用于生成hibernate校验注释的插件，会在下文说明其效果 -->

    <plugin type="tech.luoyu.ki.generator.JSR303Plugin"></plugin>

    <!-- generate entity时，生成serialVersionUID -->

    <plugin type="org.mybatis.generator.plugins.SerializablePlugin" />

    <plugin type="org.mybatis.generator.plugins.EqualsHashCodePlugin"></plugin>

    <plugin type="org.mybatis.generator.plugins.ToStringPlugin"></plugin>

    <plugin type="org.mybatis.generator.plugins.CaseInsensitiveLikePlugin"></plugin>

   

    <commentGenerator>

        <!-- 是否去除自动生成的注释 true：是： false:否 -->

        <property name="suppressAllComments" value="true" />

    </commentGenerator>

       

    <jdbcConnection driverClass="com.mysql.jdbc.Driver"

        connectionURL="jdbc:mysql://localhost:3306/knowledgeisland"

        userId="root"

        password="root">

    </jdbcConnection>

 

    <!-- 定义Java类型解析器的属性 -->

    <javaTypeResolver >

      <!-- 指定MyBatis发生器是否应该强迫java.math的使用。BigDecimal十进制数值字段,而不是代替积分类型 -->

      <property name="forceBigDecimals" value="false" />

    </javaTypeResolver>

   

    <!-- 定义属性的Java模型生成器；包生成的类将被放置的地方;指定一个目标项目生成的对象 -->

    <javaModelGenerator targetPackage="tech.luoyu.ki.entity.auto" targetProject="src/main/java">

      <property name="enableSubPackages" value="true" />

      <property name="immutable" value="false"/>

      <property name="trimStrings" value="true" />

    <!-- 设置entity的基类 -->

      <property name="rootClass" value="tech.luoyu.ki.entity.BaseEntity"/>

    </javaModelGenerator>

   

    <!-- 定义SQL映射生成器的属性 -->

    <sqlMapGenerator targetPackage="mapper.auto"  targetProject="src/main/resources"><!-- 放置生成的SQL映射文件;指定生成SQL映射的目标项目 -->

      <!-- 选择MGB是否根据基于目录和内省表来生成不同的Java包 -->

      <property name="enableSubPackages" value="true" />

    </sqlMapGenerator>

 

    <!-- 定义 Java 客户端代码生成器的属性；放置生成的接口和实现类;指定生成接口和类的目标项目 -->

    <javaClientGenerator type="XMLMAPPER" targetPackage="tech.luoyu.ki.mapper.auto"  targetProject="src/main/java">

      <property name="enableSubPackages" value="true" />

    </javaClientGenerator>

 

    <!-- 选择一个table来生成相关文件。必须要有table元素；tableName（必要）：要生成对象的表名-->

    <table schema="" tableName="sys_%">

    <property name="useActualColumnNames" value="true"/>

    </table>

 

  </context>

</generatorConfiguration>

注：红色字体为重点和需要按实际分包修改的内容，注意包名需要与1.2和1.3配置的内容一致，本章末尾会给出当前已分包的结构目录截图

附：JSR303Plugin类的代码

package tech.luoyu.ki.generator;

 

import java.sql.Types;

import java.util.List;

 

import org.mybatis.generator.api.IntrospectedColumn;

import org.mybatis.generator.api.IntrospectedTable;

import org.mybatis.generator.api.PluginAdapter;

import org.mybatis.generator.api.dom.java.Field;

import org.mybatis.generator.api.dom.java.TopLevelClass;

 

publicclass JSR303Plugin extends PluginAdapter {

 

    @Override

    publicboolean validate(List<String> warnings) {

        returntrue;

    }

 

    @Override

    publicboolean modelFieldGenerated(Field field, TopLevelClass topLevelClass, IntrospectedColumn introspectedColumn,

            IntrospectedTable introspectedTable, ModelClassType modelClassType) {

        if (true == introspectedColumn.isStringColumn()) {

            if (false == introspectedColumn.isNullable()) {

                topLevelClass.addImportedType("org.hibernate.validator.constraints.NotBlank");

                field.addAnnotation("@NotBlank");

            }

            topLevelClass.addImportedType("javax.validation.constraints.Size");

            field.addAnnotation(

                    "@Size(min = 0, max = " + introspectedColumn.getLength() + " , message = \"长度必须在{min}和{max}之间\")");

        }

 

        if (introspectedColumn.getJdbcType() == Types.INTEGER) {

            if (false == introspectedColumn.isNullable()) {

                topLevelClass.addImportedType("javax.validation.constraints.NotNull");

                field.addAnnotation("@NotNull");

            }

            topLevelClass.addImportedType("javax.validation.constraints.Max");

            field.addAnnotation("@Max(value=2147483647,message=\"最大值不能高于{value}\")");

            topLevelClass.addImportedType("javax.validation.constraints.Min");

            field.addAnnotation("@Min(value=-2147483648,message=\"最小值不能低于{value}\")");

        }

 

        returnsuper.modelFieldGenerated(field, topLevelClass, introspectedColumn, introspectedTable, modelClassType);

    }

 

}

2.4 编写生成代码类：Generator.java，该类里用到一个FileTool工具类，就是一个删除文件夹和删除文件的功能，此处就不贴出代码了

/*

 * To change this license header, choose License Headers in Project Properties.

 * To change this template file, choose Tools | Templates

 * and open the template in the editor.

 */

package tech.luoyu.ki.generator;

 

import java.io.File;

import java.io.IOException;

import java.io.InputStream;

import java.sql.SQLException;

import java.util.ArrayList;

import java.util.List;

import java.util.logging.Level;

import java.util.logging.Logger;

 

import org.mybatis.generator.api.MyBatisGenerator;

import org.mybatis.generator.config.Configuration;

import org.mybatis.generator.config.xml.ConfigurationParser;

import org.mybatis.generator.exception.InvalidConfigurationException;

import org.mybatis.generator.exception.XMLParserException;

import org.mybatis.generator.internal.DefaultShellCallback;

 

import tech.luoyu.ki.util.FileTool;

 

public class Generator {

 

         public static void main(String[] args) {

                   generate();

         }

 

         @SuppressWarnings(value = "all")

         private static void generate() {

                   String singleFileName = null;// single

                   // singleFileName = "SysUserMapper.xml";

 

                   // 1. 删除已经存在的mapper.xml

                   File file = new File(Generator.class.getResource("/").getFile());

                   File parentFile = file.getParentFile().getParentFile();

                   String autoMapperRelativePath = "src\\main\\resources\\mapper\\auto";

                   File autoMapperFile = new File(parentFile.getAbsolutePath() + File.separator + autoMapperRelativePath);

                   System.out.println(autoMapperFile.getAbsolutePath());

                   System.out.println(autoMapperFile.exists());

 

                   if (singleFileName == null) {

                            if (autoMapperFile.exists()) {

                                     FileTool.delDir(autoMapperFile.getAbsolutePath(), true);

                            }

 

                            autoMapperFile.mkdirs();

                   } else {

                            autoMapperFile = new File(parentFile.getAbsolutePath() + File.separator + autoMapperRelativePath

                                               + File.separator + singleFileName);

                            if (autoMapperFile.exists()) {

                                     FileTool.delFile(autoMapperFile.getAbsolutePath());

                            }

                   }

 

                   // 2. 重新生成mapper.xml

                   try {

                            List<String> warnings = new ArrayList<String>();

                            boolean overwrite = true;

                            ConfigurationParser cp = new ConfigurationParser(warnings);

                            InputStream stream = Generator.class.getClassLoader().getResourceAsStream("generatorConfig.xml");

                            Configuration config = cp.parseConfiguration(stream);

                            DefaultShellCallback callback = new DefaultShellCallback(overwrite);

                            MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config, callback, warnings);

                            myBatisGenerator.generate(null);

                   } catch (IOException ex) {

                            Logger.getLogger(Generator.class.getName()).log(Level.SEVERE, null, ex);

                   } catch (XMLParserException ex) {

                            Logger.getLogger(Generator.class.getName()).log(Level.SEVERE, null, ex);

                   } catch (InvalidConfigurationException ex) {

                            Logger.getLogger(Generator.class.getName()).log(Level.SEVERE, null, ex);

                   } catch (SQLException ex) {

                            Logger.getLogger(Generator.class.getName()).log(Level.SEVERE, null, ex);

                   } catch (InterruptedException ex) {

                            Logger.getLogger(Generator.class.getName()).log(Level.SEVERE, null, ex);

                   }

 

                   System.out.println("代码生成完毕");

         }

}

 

2.5 运行generator类，可以看到entity（且为每个entity生成了example），mapper接口，mapper.xml都已经生成

 

 

生成的entity里红框内容就是上文中提到的JSR303Plugin插件产生的内容，JSR303Plugin插件内的内容可以自己定制，本文的代码只对String和int做了处理

 

 

3. 测试

3.1 在controller里注入mapper，并添加映射方法，这里只是简单测试，就省略service层，直接在controller里调用mapper了

         @Resource

    SysUserMapper userMapper;

 

    @RequestMapping(value = "user/list")

    public ModelAndView showUsers() {

        Map<String, Object> model = new HashMap<String, Object>();

        model.put("user", userMapper.selectByPrimaryKey("1"));

        returnnew ModelAndView("user/list", model);

    }

3.2 编写user/list.jsp

<body>

${user.userName }

${user.mobilePhone }

</body>

 

 

 

3.3 运行测试，正常