mybatis generator为实体类生成自定义注释

悠悠 2022-12-17 01:26 194阅读 0赞

# [mybatis generator为实体类生成自定义注释（读取数据库字段的注释添加到实体类，不修改源码） ][mybatis generator_] #

我们都知道mybatis generator自动生成的注释没什么实际作用，而且还增加了代码量。如果能将注释从数据库中捞取到，不仅能很大程度上增加代码的可读性，而且减少了后期手动加注释的工作量。

# 1、首先定义注释生成插件 #

MyCommentGenerator.java

package com.ilovey.mybatis.comment;
    
    
    import org.mybatis.generator.api.IntrospectedColumn;
    import org.mybatis.generator.api.IntrospectedTable;
    import org.mybatis.generator.api.dom.java.Field;
    import org.mybatis.generator.api.dom.java.InnerClass;
    import org.mybatis.generator.api.dom.java.Method;
    import org.mybatis.generator.internal.DefaultCommentGenerator;
    
    import java.text.SimpleDateFormat;
    import java.util.Date;
    import java.util.Properties;
    
    /**
     * mybatis generator生成注释插件
     * <p>
     * Created by huhaichao on 2017/5/15.
     */
    public class MyCommentGenerator extends DefaultCommentGenerator {
        private Properties properties;
        private Properties systemPro;
        private boolean suppressDate;
        private boolean suppressAllComments;
        private String currentDateStr;
    
        public MyCommentGenerator() {
            super();
            properties = new Properties();
            systemPro = System.getProperties();
            suppressDate = false;
            suppressAllComments = false;
            currentDateStr = (new SimpleDateFormat("yyyy-MM-dd")).format(new Date());
        }
    
    
        public void addFieldComment(Field field, IntrospectedTable introspectedTable,
                                    IntrospectedColumn introspectedColumn) {
            if (suppressAllComments) {
                return;
            }
            StringBuilder sb = new StringBuilder();
            field.addJavaDocLine("/**");
            sb.append(" * ");
            sb.append(introspectedColumn.getRemarks());
            field.addJavaDocLine(sb.toString().replace("\n", " "));
            field.addJavaDocLine(" */");
        }
    
        public void addFieldComment(Field field, IntrospectedTable introspectedTable) {
    
        }
    
        public void addGeneralMethodComment(Method method, IntrospectedTable introspectedTable) {
    
        }
    
        public void addGetterComment(Method method, IntrospectedTable introspectedTable,
                                     IntrospectedColumn introspectedColumn) {
    
        }
    
        public void addSetterComment(Method method, IntrospectedTable introspectedTable,
                                     IntrospectedColumn introspectedColumn) {
    
        }
    
        public void addClassComment(InnerClass innerClass, IntrospectedTable introspectedTable, boolean markAsDoNotDelete) {
    
        }
    
        public void addClassComment(InnerClass innerClass, IntrospectedTable introspectedTable) {
        }
    
    
    }

# 2、然后为mybatisgenerator配置插件 #

<?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>
        <context id="context1">
            <plugin type="org.mybatis.generator.plugins.SerializablePlugin"/>
        
            
            <commentGenerator type="com.ilovey.mybatis.comment.MyCommentGenerator">
    
            </commentGenerator>
    
    
            <jdbcConnection driverClass="com.mysql.jdbc.Driver"
             connectionURL="jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=UTF8"
             userId="root" password="123456">
            </jdbcConnection>
            
            <javaModelGenerator targetPackage="com.ilovey.biz.entity.base"
             targetProject="ilovey.biz/src/main/java"/>
            <sqlMapGenerator targetPackage="com.ilovey.biz.mapper.base"
             targetProject="ilovey.biz/src/main/resources"/>
            <javaClientGenerator targetPackage="com.ilovey.biz.mapper.base"
             targetProject="ilovey.biz/src/main/java" type="XMLMAPPER"/>
            
            <table tableName="us_user_info"  domainObjectName="UsUserInfo">
                <generatedKey column="id" sqlStatement="MySql" identity="true"/>
            </table>
    
    
        </context>
    </generatorConfiguration>

# 3、使用mybatis generator自动生成代码 #

由于使用的是maven项目，而且使用了了自定义的插件，所以采用 main方法启动，适用场景更对，而且能将代码生成到对应的工程目录下，免去拷贝的过程（当然也可以用maven插件、控制台、eclipse插件等多种方式启动）。

注意：当前类所在的工程要添加mybatis generator的依赖包

启动类如下

package com.ilovey.mybatis;
    
    import org.mybatis.generator.api.MyBatisGenerator;
    import org.mybatis.generator.config.Configuration;
    import org.mybatis.generator.config.xml.ConfigurationParser;
    import org.mybatis.generator.internal.DefaultShellCallback;
    
    import java.io.InputStream;
    import java.util.ArrayList;
    import java.util.List;
    
    /**
     * 运行此方法生成mybatis代码
     * 生成代码自动放入对应目录
     * 配置文件targetProject应从项目名称开始到要生成到的classpath
     * Created by huhaichao on 2017/5/15.
     */
    public class MyBatisGeneratorRun {
    
        public static void main(String[] args) throws Exception{
            MyBatisGeneratorRun app = new MyBatisGeneratorRun();
    
            System.out.println(app.getClass().getResource("/").getPath());
            app.generator();
            System.out.println(System.getProperty("user.dir"));
        }
    
        public void generator() throws Exception{
    
            List<String> warnings = new ArrayList<String>();
            boolean overwrite = true;
            InputStream resourceAsStream = this.getClass().getClassLoader().getResourceAsStream("generatorConfig.xml");
            ConfigurationParser cp = new ConfigurationParser(warnings);
            Configuration config = cp.parseConfiguration(resourceAsStream);
            DefaultShellCallback callback = new DefaultShellCallback(overwrite);
            MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config, callback, warnings);
            myBatisGenerator.generate(null);
    
            for(String warning:warnings){
                System.out.println(warning);
            }
        }
    }

再贴下项目的maven依赖，有需要的可以看下

<?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>party.lovey</groupId>
        <artifactId>generator</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <packaging>jar</packaging>
    
        <dependencies>
            <dependency>
                <groupId>org.mybatis.generator</groupId>
                <artifactId>mybatis-generator-core</artifactId>
                <version>1.3.6</version>
            </dependency>
    
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>5.1.29</version>
            </dependency>
        </dependencies>
        
    </project>

# 4、生成效果 #

package com.ilovey.biz.entity.base;
    
    import java.io.Serializable;
    import java.util.Date;
    
    public class UsUserInfo implements Serializable {
        /**
         * 
         */
        private Integer id;
    
        /**
         * 用户id
         */
        private Integer userId;
    
        /**
         * 昵称
         */
        private String nickName;
    
        /**
         * 头像
         */
        private String headImage;
    
        /**
         * 手机号码
         */
        private String mobile;
    
        /**
         * 性别（0保密，1男，2女）
         */
        private Integer sex;
    
        /**
         * 地区
         */
        private Integer region;
    
        /**
         * 个性签名
         */
        private String signature;
    
        /**
         * 创建时间
         */
        private Date createTime;
    
        /**
         * 更新时间
         */
        private Date updateTime;
    
        //setter 和 getter方法省略
    }

此外，mybatis的插件还有着更强大的功能，比如支持分页功能，修复因别名造成的delete语句错误等，需要这些插件的朋友可以在底部留言。

[mybatis generator_]: https://www.cnblogs.com/cblogs/p/9432129.html