實習小結（四）--- MyBatis Generator使用
阿新 • • 發佈：2018-04-06
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第一次聽聞MyBatis Generator插件很是驚訝，已經有這麽便捷方式的工具通過數據庫表來自動生成實體類，映射文件，接口以及幫助類，而且可以通過自己寫方法來增加中文註釋，遂來學習一波。首先先建一個Maven的java項目
項目的目錄結構
1、首先是pom.xml中的配置
<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"
2、MyCommentGenerator.java為生成中文註釋的方法
package com.mybatis.generator;
import static org.mybatis.generator.internal.util.StringUtility.isTrue;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Properties;
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.CompilationUnit;
import org.mybatis.generator.api.dom.java.Field;
import org.mybatis.generator.api.dom.java.InnerClass;
import org.mybatis.generator.api.dom.java.InnerEnum;
import org.mybatis.generator.api.dom.java.JavaElement;
import org.mybatis.generator.api.dom.java.Method;
import org.mybatis.generator.api.dom.java.Parameter;
import org.mybatis.generator.api.dom.xml.XmlElement;
import org.mybatis.generator.config.MergeConstants;
import org.mybatis.generator.config.PropertyRegistry;
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().replace("\n", " "));
innerClass.addJavaDocLine(" */");
}
public void addEnumComment(InnerEnum innerEnum, IntrospectedTable introspectedTable) {
if (suppressAllComments) {
return;
}
StringBuilder sb = new StringBuilder();
innerEnum.addJavaDocLine("/**");
sb.append(" * ");
sb.append(introspectedTable.getFullyQualifiedTable());
innerEnum.addJavaDocLine(sb.toString().replace("\n", " "));
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().replace("\n", " "));
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().replace("\n", " "));
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(" * ");
sb.append(introspectedColumn.getRemarks());
method.addJavaDocLine(sb.toString().replace("\n", " "));
sb.setLength(0);
sb.append(" * @return ");
sb.append(introspectedColumn.getActualColumnName());
sb.append(" ");
sb.append(introspectedColumn.getRemarks());
method.addJavaDocLine(sb.toString().replace("\n", " "));
method.addJavaDocLine(" */");
}
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().replace("\n", " "));
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().replace("\n", " "));
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().replace("\n", " "));
sb.setLength(0);
sb.append(" * @author ");
sb.append(systemPro.getProperty("user.name"));
sb.append(" ");
sb.append(currentDateStr);
innerClass.addJavaDocLine(" */");
}
}
View Code
3、在resources下增加配置信息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>
<context id="context1" targetRuntime="MyBatis3" >
<!-- 指定生成的java文件的編碼,沒有直接生成到項目時中文可能會亂碼 -->
<property name="javaFileEncoding" value="UTF-8"/>
<!-- 生成的pojo，將implements Serializable-->
<plugin type="org.mybatis.generator.plugins.SerializablePlugin"></plugin>
<!-- 註釋, 這裏的type裏寫的是你的實現類的類全路徑 -->
<commentGenerator type="com.mybatis.generator.MyCommentGenerator"></commentGenerator>
<!-- 數據庫連接 mysql配置 -->
<jdbcConnection driverClass="com.mysql.jdbc.Driver"
connectionURL="jdbc:mysql://localhost:3306/test" userId="root" password="root">
<property name="useInformationSchema" value="true"></property>
</jdbcConnection>
<!--
默認false，把JDBC DECIMAL 和 NUMERIC 類型解析為 Integer
true，把JDBC DECIMAL 和 NUMERIC 類型解析為java.math.BigDecimal
-->
<javaTypeResolver>
<property name="forceBigDecimals" value="false" />
</javaTypeResolver>
<!-- 生成model模型，對應的包路徑，以及文件存放路徑(targetProject)，targetProject可以指定具體的路徑
也可以使用“MAVEN”來自動生成，這樣生成的代碼會在target/generatord-source目錄下 -->
<javaModelGenerator targetPackage="model"
targetProject="I:\mybatisGenerator">
<property name="enableSubPackages" value="true" />
<!-- 從數據庫返回的值被清理前後的空格 -->
<property name="trimStrings" value="true" />
</javaModelGenerator>
<!--對應的mapper.xml文件 -->
<sqlMapGenerator targetPackage="dao"
targetProject="I:\mybatisGenerator">
<property name="enableSubPackages" value="true" />
</sqlMapGenerator>
<!-- 對應的Mapper接口類文件 -->
<javaClientGenerator type="XMLMAPPER"
targetPackage="dao" targetProject="I:\mybatisGenerator">
<property name="enableSubPackages" value="true" />
</javaClientGenerator>
<!-- 生成哪些些表，tableName對應數據庫表，domainObjectName對應實體類名 -->
<table schema="" tableName="power" domainObjectName="power"
enableCountByExample="true" enableUpdateByExample="true"
enableDeleteByExample="true" enableSelectByExample="true"
selectByExampleQueryId="true">
</table>
</context>
</generatorConfiguration>
4、最後編寫一個mian方法用來生成需要的文件
package com.mybatis.generator;
import java.io.IOException;
import java.io.InputStream;
import java.net.URISyntaxException;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
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;
public class StartUp {
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.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();
}
}
}
按理說運行StartUp就會生成所需要的實體類，映射文件等，
但是我目前遇到一個問題就是運行StartUp之後，會發生異常，內容如下：
異常的意思就是generatorConfig.xml配置文件中，context元素中的內容順序或其他內容不正確，我在核對了幾次之後依然沒有找到解決問題的方法，並且該項目是模仿園內其他大神的，不知為何在我這裏不能運行。
目前先把問題丟在這裏，等找到資料或者得到大神的解答後再來處理。。。。
參考博客
[1]Mybatis Generator的model生成中文註釋,支持oracle和mysql(通過實現CommentGenerator接口的方法來實現)
http://www.cnblogs.com/NieXiaoHui/p/6094144.html
[2]MyBatis Generator 配置詳解
https://blog.csdn.net/testcs_dn/article/details/79295065
實習小結（四）--- MyBatis Generator使用