mybatis-generator自定义注释生成

最近做的项目发现没有中文注释，故查找资料，特此记录。

本文所用的是基于mybatis-generator 1.3.2版本来完成的。

mybatis-generator 自动生成的代码注释是很反人类的,通常我们在使用的时候都是按照如下设置关闭注释:

<commentGenerator>
    <!--  关闭自动生成的注释  -->
    <property name="suppressAllComments" value="true" />
</commentGenerator>

不过在mybatis-generator官方文档中commentGenerator一节中有这么一段说明：The default implementation is org.mybatis.generator.internal.DefaultCommentGenerator. The default implementation is designed for extensibility if you only want to modify certain behaviors.

既然是可扩展的,那么该如何做呢?文档中也有说明,只需要实现 org.mybatis.generator.api.CommentGenerator接口,同时有一个public的构造函数,然后为commentGenerator添加属性type,并将其值设置为实现类的全路径即可。

1.实现CommentGenerator接口

当然首先你的工程中要有mybatis-generator-core这个jar包.相关pom如下:

<dependency>
    <groupId>org.mybatis.generator</groupId>
    <artifactId>mybatis-generator-core</artifactId>
    <!-- 注意版本.这里我使用的是1.3.2 -->
    <version>1.3.2</version>
</dependency>

正文,实现CommentGenerator接口,当然继承默认的实现DefaultCommentGenerator也行.然后实现或者是重写自己需要的方法.过程中最好是参照着DefaultCommentGenerator里面的代码来做.

没什么要多说的,下文是我的实现.

 package com.test.util;
 import org.mybatis.generator.api.CommentGenerator;
 import org.mybatis.generator.api.IntrospectedColumn;
 import org.mybatis.generator.api.IntrospectedTable;
 import org.mybatis.generator.api.dom.java.*;
 import org.mybatis.generator.api.dom.xml.XmlElement;
 import org.mybatis.generator.config.MergeConstants;
 import org.mybatis.generator.config.PropertyRegistry;

 import java.text.SimpleDateFormat;
 import java.util.Date;
 import java.util.Properties;

 import static org.mybatis.generator.internal.util.StringUtility.isTrue;

 /**
  * mybatis generator 自定义comment生成器.
  * 基于MBG 1.3.2.
  *
  */
 public class MyCommentGenerator implements CommentGenerator {

     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 addJavaFileComment(CompilationUnit compilationUnit) {
         // add no file level comments by default
         return;
     }

     /**
      * Adds a suitable comment to warn users that the element was generated, and
      * when it was generated.
      */
     public void addComment(XmlElement xmlElement) {
         return;
     }

     public void addRootComment(XmlElement rootElement) {
         // add no document level comments by default
         return;
     }

     public void addConfigurationProperties(Properties properties) {
         this.properties.putAll(properties);

         suppressDate = isTrue(properties.getProperty(PropertyRegistry.COMMENT_GENERATOR_SUPPRESS_DATE));

         suppressAllComments = isTrue(properties.getProperty(PropertyRegistry.COMMENT_GENERATOR_SUPPRESS_ALL_COMMENTS));
     }

     /**
      * This method adds the custom javadoc tag for. You may do nothing if you do
      * not wish to include the Javadoc tag - however, if you do not include the
      * Javadoc tag then the Java merge capability of the eclipse plugin will
      * break.
      *
      * @param javaElement the java element
      */
     protected void addJavadocTag(JavaElement javaElement, boolean markAsDoNotDelete) {
         javaElement.addJavaDocLine(" *");
         StringBuilder sb = new StringBuilder();
         sb.append(" * ");
         sb.append(MergeConstants.NEW_ELEMENT_TAG);
         if (markAsDoNotDelete) {
             sb.append(" do_not_delete_during_merge");
         }
         String s = getDateString();
         if (s != null) {
             sb.append(' ');
             sb.append(s);
         }
         javaElement.addJavaDocLine(sb.toString());
     }

     /**
      * This method returns a formated date string to include in the Javadoc tag
      * and XML comments. You may return null if you do not want the date in
      * these documentation elements.
      *
      * @return a string representing the current timestamp, or null
      */
     protected String getDateString() {
         String result = null;
         if (!suppressDate) {
             result = currentDateStr;
         }
         return result;
     }

     public void addClassComment(InnerClass innerClass, IntrospectedTable introspectedTable) {
         if (suppressAllComments) {
             return;
         }
         StringBuilder sb = new StringBuilder();
         innerClass.addJavaDocLine("/**");
         sb.append(" * ");
         sb.append(introspectedTable.getFullyQualifiedTable());
         sb.append(" ");
         sb.append(getDateString());
         innerClass.addJavaDocLine(sb.toString());
         innerClass.addJavaDocLine(" */");
     }

     public void addEnumComment(InnerEnum innerEnum, IntrospectedTable introspectedTable) {
         if (suppressAllComments) {
             return;
         }

         StringBuilder sb = new StringBuilder();

         innerEnum.addJavaDocLine("/**");
         //      addJavadocTag(innerEnum, false);
         sb.append(" * ");
         sb.append(introspectedTable.getFullyQualifiedTable());
         innerEnum.addJavaDocLine(sb.toString());
         innerEnum.addJavaDocLine(" */");
     }

     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());

         //      addJavadocTag(field, false);

         field.addJavaDocLine(" */");
     }

     public void addFieldComment(Field field, IntrospectedTable introspectedTable) {
         if (suppressAllComments) {
             return;
         }

         StringBuilder sb = new StringBuilder();

         field.addJavaDocLine("/**");
         sb.append(" * ");
         sb.append(introspectedTable.getFullyQualifiedTable());
         field.addJavaDocLine(sb.toString());
         field.addJavaDocLine(" */");
     }

     public void addGeneralMethodComment(Method method, IntrospectedTable introspectedTable) {
         if (suppressAllComments) {
             return;
         }
         //      method.addJavaDocLine("/**");
         //      addJavadocTag(method, false);
         //      method.addJavaDocLine(" */");
     }

     public void addGetterComment(Method method, IntrospectedTable introspectedTable,
                                  IntrospectedColumn introspectedColumn) {
         if (suppressAllComments) {
             return;
         }

         method.addJavaDocLine("/**");

         StringBuilder sb = new StringBuilder();
         sb.append(" * 获取");
         sb.append(introspectedColumn.getRemarks());
         method.addJavaDocLine(sb.toString());

         sb.setLength(0);
         sb.append(" * @return ");
         sb.append(introspectedColumn.getActualColumnName());
         sb.append(" ");
         sb.append(introspectedColumn.getRemarks());
         method.addJavaDocLine(sb.toString());

         //      addJavadocTag(method, false);

         method.addJavaDocLine(" */");
     }

     public void addSetterComment(Method method, IntrospectedTable introspectedTable,
                                  IntrospectedColumn introspectedColumn) {
         if (suppressAllComments) {
             return;
         }

         method.addJavaDocLine("/**");
         StringBuilder sb = new StringBuilder();
         sb.append(" * 设置");
         sb.append(introspectedColumn.getRemarks());
         method.addJavaDocLine(sb.toString());

         Parameter parm = method.getParameters().get(0);
         sb.setLength(0);
         sb.append(" * @param ");
         sb.append(parm.getName());
         sb.append(" ");
         sb.append(introspectedColumn.getRemarks());
         method.addJavaDocLine(sb.toString());

         //      addJavadocTag(method, false);

         method.addJavaDocLine(" */");
     }

     public void addClassComment(InnerClass innerClass, IntrospectedTable introspectedTable, boolean markAsDoNotDelete) {
         if (suppressAllComments) {
             return;
         }

         StringBuilder sb = new StringBuilder();

         innerClass.addJavaDocLine("/**");
         sb.append(" * ");
         sb.append(introspectedTable.getFullyQualifiedTable());
         innerClass.addJavaDocLine(sb.toString());

         sb.setLength(0);
         sb.append(" * @author ");
         sb.append(systemPro.getProperty("user.name"));
         sb.append(" ");
         sb.append(currentDateStr);

         //      addJavadocTag(innerClass, markAsDoNotDelete);

         innerClass.addJavaDocLine(" */");
     }
 }

但是，通过实现CommentGenerator接口的一些不足,毕竟只是实现了CommentGenerator接口,在里面的方法再怎么改,有效的也只是针对model类,并且使用的人大概也发现了,里面的addClassComment方法都知道是在类文件上面生成注释,但是无论我们在这个方法实现里写什么都没有效果,其实因为MGB默认是没有调用这个方法的,这个时候如果有需求希望生成的类文件自动加了类文档说明就办不到了,而如果在源代码的基础上修改,就好办多了,想怎么改就怎么改,只要找对地方,什么样的需要都可以自己写代码来实现.

 <?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">

 <!-- 配置Run As Maven build : Goals 参数 : mybatis-generator:generate -Dmybatis.generator.overwrite=true -->
 <!-- 配置 tableName,使用 Run As Maven build 生成 dao model 层 -->
 <generatorConfiguration>
     <!-- 配置文件路径 -->
     <properties resource="generatorConfig.properties"/>

     <context id="DB2Tables" targetRuntime="MyBatis3">
         <!-- 指定生成的java文件的编码,没有直接生成到项目时中文可能会乱码 -->
         <property name="javaFileEncoding" value="UTF-8"/>

         <!-- 生成的pojo，将implements Serializable -->
         <plugin type="org.mybatis.generator.plugins.SerializablePlugin"></plugin>
         <!-- 这里的type里写的是你的实现类的类全路径 -->
         <commentGenerator type="com.test.util.MyCommentGenerator">
         </commentGenerator>
      <!--   <commentGenerator>
             <property name="suppressDate" value="true"/>
             &lt;!&ndash;关闭注释&ndash;&gt;
             <property name="suppressAllComments" value="true"/>
         </commentGenerator>-->

         <!--数据库连接信息 -->
         <jdbcConnection driverClass="${jdbc.driver}" connectionURL="${jdbc.url}" userId="${jdbc.username}"
                         password="${jdbc.password}">
         </jdbcConnection>

         <!--生成的model 包路径 -->
        <javaModelGenerator targetPackage="${model.package}" targetProject="${target.project}">
             <property name="enableSubPackages" value="ture"/>
             <property name="trimStrings" value="true"/>
         </javaModelGenerator>

         <!--生成xml mapper文件 路径 -->
         <sqlMapGenerator targetPackage="${xml.mapper.package}" targetProject="${target.project}">
             <property name="enableSubPackages" value="true"/>
         </sqlMapGenerator>

         <!-- 生成的Dao接口 的包路径 -->
         <javaClientGenerator type="XMLMAPPER" targetPackage="${dao.package}" targetProject="${target.project}">
             <property name="enableSubPackages" value="true"/>
         </javaClientGenerator>

         <!--对应数据库表名 -->
         <table tableName="t_user" domainObjectName="User">
             <property name="enableCountByExample" value="false"/>
             <property name="enableDeleteByExample" value="false"/>
             <property name="enableDeleteByPrimaryKey" value="false"/>
             <property name="enableInsert" value="false"/>
             <property name="enableSelectByPrimaryKey" value="false"/>
             <property name="enableUpdateByExample" value="false"/>
             <property name="enableUpdateByPrimaryKey" value="false"/>
             <property name="selectByExampleQueryId" value="true"/>
             <property name="selectByPrimaryKeyQueryId" value="false"/>
             <!--自动生成主键，可以代替useGeneratedKeys，大家不用删-->
             <generatedKey column="id" sqlStatement="Mysql" type="post" identity="true"/>
         </table>
     </context>
 </generatorConfiguration>

# \u6570\u636E\u5E93\u9A71\u52A8jar \u8DEF\u5F84
drive.class.path=E:\\maven-repository\\reps\\mysql\\mysql-connector-java\\5.1.29\\mysql-connector-java-5.1.29.jar

# \u6570\u636E\u5E93\u8FDE\u63A5\u53C2\u6570
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8
jdbc.username=root
jdbc.password=root

# \u5305\u8DEF\u5F84\u914D\u7F6E
model.package=com.test.model
dao.package=com.test.dao
xml.mapper.package=com.test.dao
target.project=src/main/java

2.使用Java方式运行MBG

 package com.test.util;

 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 java.io.IOException;
 import java.io.InputStream;
 import java.net.URISyntaxException;
 import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.List;

 /**
  * 描述：使用Java方式运行MBG
  *
  *
  */
 public class GeneratorStartUp {
     public static void main(String[] args) throws URISyntaxException {
         try {
             List<String> warnings = new ArrayList<String>();
             boolean overwrite = true;
             ClassLoader classloader = Thread.currentThread().getContextClassLoader();
             InputStream is = classloader.getResourceAsStream("generatorConfig-Java.xml");
             ConfigurationParser cp = new ConfigurationParser(warnings);
             Configuration config = cp.parseConfiguration(is);
             DefaultShellCallback callback = new DefaultShellCallback(overwrite);
             MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config, callback, warnings);
             myBatisGenerator.generate(null);
         } catch (SQLException e) {
             e.printStackTrace();
         } catch (IOException e) {
             e.printStackTrace();
         } catch (InterruptedException e) {
             e.printStackTrace();
         } catch (InvalidConfigurationException e) {
             e.printStackTrace();
         } catch (XMLParserException e) {
             e.printStackTrace();
         }
     }
 }