Mybatis反向生成模型带中文注释
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2022-03-08 18:29:15
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mybatis可以通过数据库表直接替我们生成模型类和mappper文件。
这里说一下怎么配置，尤其是如何加上中文注释。当前前提是数据表和字段有中文注释。
比如这样的：
下面配置自动生成模型类和mapper类还有mapper的xml文件。
网上关于如何使用mybatis-generator生成Java对象的文章很多，这里不详细说了。大家可以到百度上so一下，比如http://www.cnblogs.com/smileberry/p/4145872.html，http://www.cnblogs.com/yjmyzz/p/4210554.html
假设我们已经设计好了表结构，表和字段都有自己的注释（其实中英文倒无所谓）。
下面是反向生成的过程：
在类路径下新建generatorConfig.xml，配置如下
<?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>
<!--指定特定数据库的jdbc驱动jar包的位置-->
<classPathEntry location="${jdbc.driverLocation}"/>
<context id="default" targetRuntime="MyBatis3">
<!--jdbc的数据库连接 -->
<jdbcConnection
driverClass="${jdbc.driverClass}"
connectionURL="${jdbc.connectionURL}"
userId="${jdbc.userId}"
password="${jdbc.password}">
</jdbcConnection>
<javaTypeResolver>
<property name="forceBigDecimals" value="true"/>
</javaTypeResolver>
<javaModelGenerator targetPackage="comxxx.model"
targetProject="src/main/java">
<property name="enableSubPackages" value="false"/>
<property name="constructorBased" value="true"/>
<property name="trimStrings" value="true"/>
<property name="immutable" value="false"/>
</javaModelGenerator>
<sqlMapGenerator targetPackage="com.xxx.mapper"
targetProject="src/main/resources">
<property name="enableSubPackages" value="true"/>
</sqlMapGenerator>
<javaClientGenerator targetPackage="com.xxx.mapper"
targetProject="src/main/java"
type="XMLMAPPER">
<property name="enableSubPackages" value="false"/>
</javaClientGenerator>
<table tableName="import_goods_quantity"
enableCountByExample="false" enableUpdateByExample="false"
enableDeleteByExample="false" enableSelectByExample="false"
selectByExampleQueryId="false">
<!--<generatedKey identity="true" sqlStatement="MySql" column="id"/>-->
</table>
</context>
</generatorConfiguration>
generatorConfiguration 有一个子标签
<properties resource="xxx.properties"></properties>
可以引入配置变量。
配置好以后就可以使用插件mybatis-generator-maven-plugin生成了。
<plugin> <groupId>org.mybatis.generator</groupId> <artifactId>mybatis-generator-maven-plugin</artifactId> <version>1.3.5</version> <configuration> <verbose>true</verbose> <overwrite>true</overwrite> </configuration> </plugin>
我们这里使用的是1.3.5版本。
现在用mybatis-generator:generate就可以生成Java类和xml文件到指定目录了。
这样生成的类注释是自动的、毫无意义的时间描述，类似于
@mbg.generated
我们希望数据库里的注释能够拿过来，怎么搞呢？
新建一个maven工程，坐标比如是
<groupId>com.xxx</groupId> <artifactId>comment_generator</artifactId> <version>1.0-SNAPSHOT</version>
引入依赖
<dependency>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-core</artifactId>
<version>1.3.5</version>
</dependency>
新建注释配置类
public class MybatisCommentGenerator implements CommentGenerator {
private Properties properties;
private Properties systemPro;
private boolean suppressDate;
private boolean suppressAllComments;
private String currentDateStr;
public MybatisCommentGenerator() {
super();
properties = new Properties();
systemPro = System.getProperties();
suppressDate = false;
suppressAllComments = false;
currentDateStr = (new SimpleDateFormat("yyyy-MM-dd")).format(new Date());
}
/**
* Adds properties for this instance from any properties configured in the
* CommentGenerator configuration.
* <p> * This method will be called before any of the other methods.
*
* @param properties All properties from the configuration
*/
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));
}
/** *
* @param field the field
* @param introspectedTable the introspected table
* @param introspectedColumn
*/
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(" */");
}
/**
* Adds the field comment.
*
* @param field the field
* @param introspectedTable
*/
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 addModelClassComment(TopLevelClass topLevelClass, IntrospectedTable introspectedTable) {
if (suppressAllComments) {
return;
}
StringBuilder sb = new StringBuilder();
topLevelClass.addJavaDocLine("/**");
sb.append(" * ");
sb.append(introspectedTable.getRemarks());
sb.append(" ");
sb.append(introspectedTable.getTableType());
sb.append(" ");
sb.append(getDateString());
topLevelClass.addJavaDocLine(sb.toString());
topLevelClass.addJavaDocLine(" */");
}
/**
* Adds the inner class comment.
*
* @param innerClass the inner class
* @param introspectedTable
*/
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(" */");
}
/**
* Adds the inner class comment.
*
* @param innerClass the inner class
* @param introspectedTable the introspected table
* @param markAsDoNotDelete
*/
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(" */");
}
/**
* Adds the enum comment.
*
* @param innerEnum the inner enum
* @param introspectedTable
*/
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(" */");
}
/**
* Adds the getter comment.
*
* @param method the method
* @param introspectedTable the introspected table
* @param introspectedColumn
*/
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(" */");
}
/**
* Adds the setter comment.
*
* @param method the method
* @param introspectedTable the introspected table
* @param introspectedColumn
*/
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(" */");
}
/**
* Adds the general method comment.
*
* @param method the method
* @param introspectedTable
*/
public void addGeneralMethodComment(Method method, IntrospectedTable introspectedTable) {
if (suppressAllComments) {
return;
}
method.addJavaDocLine("/**");
// addJavadocTag(method, false);
StringBuilder sb = new StringBuilder();
sb.append(" * ");
sb.append(MergeConstants.NEW_ELEMENT_TAG);
String s = method.getName();
sb.append(' ');
sb.append(s);
method.addJavaDocLine(sb.toString());
method.addJavaDocLine(" */");
}
public void addJavaFileComment(CompilationUnit compilationUnit) {
}
public void addComment(XmlElement xmlElement) {
}
public void addRootComment(XmlElement rootElement) {
}
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());
}
protected String getDateString() {
String result = null;
if (!suppressDate) {
result = currentDateStr;
}
return result;
}
}
将这个工程install一下。（可以关闭了，除非你要继续修改）
回到前面需要反向生成的工程。
在generatorConfig.xml中，修改
commentGenerator
元素为
<commentGenerator type="com.xxx.mybatis.MybatisCommentGenerator">
<property name="suppressDate" value="false"/>
<property name="suppressAllComments" value="false"/>
</commentGenerator>
其中type指向刚才工程里的注释配置类。suppressDate依个人喜好可有可无。
修改generator插件，引入刚才新建的工程依赖：
<plugin>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-maven-plugin</artifactId>
<version>1.3.5</version>
<configuration>
<verbose>true</verbose>
<overwrite>true</overwrite>
</configuration>
<dependencies>
<dependency>
<groupId>com.xxx</groupId>
<artifactId>comment_generator</artifactId>
<version>1.0-SNAPSHOT</version>
</dependency>
</dependencies>
</plugin>
再次运行插件，可以看到模型类上有了我们在数据库里写好的注释。
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