使用Mybatis-Generator自动生成文件

前言：Mybatis属于半自动ORM，我们可以利用Mybatis-Generator来帮我们自动生成相关文件。此处以mysql为例.

mybatis-generator + tk.mybatis

pom.xml

maven 依赖

<!-- mybatis-generator -->
<dependency>
  <groupId>org.mybatis.generator</groupId>
  <artifactId>mybatis-generator-core</artifactId>
  <version>1.3.7</version>
</dependency>
<!-- tk.mybatis -->
<dependency>
  <groupId>tk.mybatis</groupId>
  <artifactId>mapper</artifactId>
  <version>4.1.5</version>
</dependency>

插件

<plugin>
  <groupId>org.mybatis.generator</groupId>
  <artifactId>mybatis-generator-maven-plugin</artifactId>
  <version>1.3.7</version>
  <configuration>
    <!-- mybatis用于生成代码的配置文件 -->
    <configurationFile>src/main/resources/generatorConfig.xml</configurationFile>
    <verbose>true</verbose>
    <overwrite>true</overwrite>
  </configuration>

  <dependencies>
    <dependency>
      <groupId>org.mybatis.generator</groupId>
      <artifactId>mybatis-generator-core</artifactId>
      <version>1.3.7</version>
    </dependency>
    <dependency>
      <groupId>tk.mybatis</groupId>
      <artifactId>mapper</artifactId>
      <version>4.1.5</version>
    </dependency>
  </dependencies>
</plugin>

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>
    <classPathEntry location="E:\repository\mysql\mysql-connector-java\8.0.16\mysql-connector-java-8.0.16.jar"/>

    <context id="Mysql" targetRuntime="MyBatis3Simple" defaultModelType="flat">
        <property name="javaFileEncoding" value="UTF-8"/>
        <plugin type="tk.mybatis.mapper.generator.MapperPlugin">
            <property name="mappers" value="tk.mybatis.mapper.common.Mapper"/>
            <!-- caseSensitive默认false，当数据库表名区分大小写时，可以将该属性设置为true -->
            <property name="caseSensitive" value="true"/>
        </plugin>

        <!-- 配置jdbc连接信息 -->
        <jdbcConnection driverClass="com.mysql.cj.jdbc.Driver"
                        connectionURL="jdbc:mysql://127.0.0.1:3306/ssm"
                        userId="root"
                        password="123456">
            <!-- 防止生成不同库的同名表 -->
            <property name="nullCatalogMeansCurrent" value="true"/>
        </jdbcConnection>

        <!-- 配置model包名和输出路径 -->
        <javaModelGenerator targetPackage="com.husky.ssm.dao.entity" targetProject="src/main/java"/>

        <!-- 配置mapper.xml的生成目录和输出路径， 如mybatis.mapper.matrix 代表将生成的mapper.xml -->
        <sqlMapGenerator targetPackage="mapper" targetProject="src/main/resources"/>

        <!-- 配置mapper.java的包名和输出路径 -->
        <javaClientGenerator targetPackage="com.husky.ssm.dao.mapper" targetProject="src/main/java"
                             type="XMLMAPPER"/>

        <!-- 配置需要自动生成mapper的表名， 一个table标签配置一张表，可同时配置个table标签 -->
        <table tableName="book"></table>
    </context>
</generatorConfiguration>

配置启动

运行，就能自动mapper与entity

mybatis-generator自定义注释

这个没有什么用，可以跳过,但既然研究了一下，就做个笔记

mybatis-generator自带的注释非常差，使用时需要增加配置去除自动生成的注释

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

实现CommentGenerator接口

package org.mybatis.generator.internal;

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 java.util.Set;

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

/**
 * @author xxx
 * @description: 参考大佬
 * @date: 2019/11/11
 */
public class DefaultCommentGenerator implements CommentGenerator {
    private Properties properties;
    private Properties systemPro;
    private boolean suppressDate;
    private boolean suppressAllComments;
    private String currentDateStr;

    public DefaultCommentGenerator() {
        super();
        properties = new Properties();
        systemPro = System.getProperties();
        suppressDate = false;
        suppressAllComments = false;
        currentDateStr = (new SimpleDateFormat("yyyy-MM-dd")).format(new Date());
    }

    @Override
    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.
     */
    @Override
    public void addComment(XmlElement xmlElement) {
        return;
    }

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

    @Override
    public void addGeneralMethodAnnotation(Method method, IntrospectedTable introspectedTable,
                                           Set<FullyQualifiedJavaType> set) {

    }

    @Override
    public void addGeneralMethodAnnotation(Method method, IntrospectedTable introspectedTable, IntrospectedColumn introspectedColumn, Set<FullyQualifiedJavaType> set) {

    }

    @Override
    public void addFieldAnnotation(Field field, IntrospectedTable introspectedTable, Set<FullyQualifiedJavaType> set) {

    }

    @Override
    public void addFieldAnnotation(Field field, IntrospectedTable introspectedTable, IntrospectedColumn introspectedColumn, Set<FullyQualifiedJavaType> set) {

    }

    @Override
    public void addClassAnnotation(InnerClass innerClass, IntrospectedTable introspectedTable, Set<FullyQualifiedJavaType> set) {

    }

    @Override
    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;
    }

    @Override
    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(" */");
    }

    @Override
    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(" */");
    }

    @Override
    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(" */");
    }

    @Override
    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(" */");
    }

    @Override
    public void addModelClassComment(TopLevelClass topLevelClass, IntrospectedTable introspectedTable) {

    }

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

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

        method.addJavaDocLine("/**");

        StringBuilder sb = new StringBuilder();
        sb.append(" * ");
        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(" */");
    }

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


        method.addJavaDocLine("/**");
        StringBuilder sb = new StringBuilder();
        sb.append(" * ");
        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(" */");
    }

    @Override
    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(" */");
    }
}

generatorConfig.xml

<commentGenerator type="org.mybatis.generator.internal.DefaultCommentGenerator">
</commentGenerator>

使用tk.mapper

https://github.com/abel533/Mapper

<!-- tk.mybatis -->
<dependency>
  <groupId>tk.mybatis</groupId>
  <artifactId>mapper</artifactId>
  <version>4.1.5</version>
</dependency>

generatorConfig.xml配置

<?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="Mysql" targetRuntime="MyBatis3Simple" defaultModelType="flat">
	<property name="javaFileEncoding" value="UTF-8"/>
    <plugin type="tk.mybatis.mapper.generator.MapperPlugin">
      <property name="mappers" value="tk.mybatis.mapper.common.Mapper"/>
      <!-- caseSensitive默认false，当数据库表名区分大小写时，可以将该属性设置为true -->
      <property name="caseSensitive" value="true"/>
    </plugin>

        <!-- 配置jdbc连接信息 -->
        <jdbcConnection driverClass="com.mysql.cj.jdbc.Driver"
                        connectionURL="jdbc:mysql://127.0.0.1:3306/ssm"
                        userId="root"
                        password="123456">
            <!-- 防止生成不同库的同名表 -->
            <property name="nullCatalogMeansCurrent" value="true"/>
        </jdbcConnection>

    <!-- 配置model包名和输出路径-->
    <javaModelGenerator targetPackage="com.husky.ssm.dao.entity" targetProject="../src/main/java"/>

    <!-- 配置mapper.xml的生成目录和输出路径， 如mybatis.mapper.matrix 代表将生成的mapper.xml -->
    <sqlMapGenerator targetPackage="mapper" targetProject="../src/main/resources"/>

    <!-- 配置mapper.java的包名和输出路径-->
    <javaClientGenerator targetPackage="com.husky.ssm.dao.mapper" targetProject="../src/main/java"
                         type="XMLMAPPER"/>

    <!-- 配置需要自动生成mapper的表名， 一个table标签配置一张表，可同时配置个table标签 -->
    <table tableName="book"></table>
  </context>
</generatorConfiguration>

运行脚本

@echo off

echo start to generate mapper ......
set "CURRENT_DIR=%cd%"
set "EXEC_JAR=%CURRENT_DIR%/lib/framework-mapper-generator-1.0.0-RELEASE.jar"
set "CONFIG_PATH=%CURRENT_DIR%/conf/generatorConfig-mysql.xml"
java -jar %EXEC_JAR% %CONFIG_PATH%

if %errorlevel% == 0 echo mapper generate successfully, press any key to exit.
if %errorlevel% == 1 echo mapper generate failed.
pause