一：準備工作

1.資料庫，資料表，例如：postgres spring(資料庫) user_t（表）
2.maven專案（例如：SSMLTest）

二:開始

第一步：配置Maven 的pom.xml檔案
也就是在pom.xml檔案中加入下面這一段程式碼

<plugin>
            <groupId>org.mybatis.generator</groupId>
            <artifactId>mybatis-generator-maven-plugin</artifactId>
 

            <version>1.3.2</version>
            <configuration>
                <verbose>true</verbose>
                <overwrite>true</overwrite>
            </configuration>
        </plugin>

第二步：generatorConfig.xml放置路徑

第三步：配置generatorConfig.xml檔案

<?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="C:/Users/witon/.m2/repository/org/postgresql/postgresql/9.4-1201-jdbc41/postgresql-9.4-1201-jdbc41.jar"
 
></classPathEntry>
        <context id="context" targetRuntime="MyBatis3" >  
            <commentGenerator>
                <property name="suppressDate" value="true"/>
                <!-- 是否去除自動生成的註釋true 是 FALSE 否 -->
                <property name="suppressAllComments" value="true"/>
            </commentGenerator>

            <!-- 資料庫連線URL 使用者名稱，密碼 -->
            <jdbcConnection driverClass="org.postgresql.Driver" connectionURL="jdbc:postgresql://127.0.0.1:5432/spring" userId="root" password="postgres"/>

            <javaTypeResolver>
                <property name="forceBigDecimals" value="false"/>
            </javaTypeResolver>

            <!-- 生成模型的包名和位置 -->
            <javaModelGenerator targetPackage="com.zoey.test.domain" targetProject="src/main/java">
            </javaModelGenerator>

            <!-- 生成對映檔案的包名和位置-->    
           <sqlMapGenerator targetPackage="com.zoey.test.mapping" targetProject="src/main/java">    
                <property name="enableSubPackages" value="true"/>    
           </sqlMapGenerator>   

            <!-- 生成Dao的包名和位置 -->
            <javaClientGenerator type="XMLMAPPER" targetPackage="com.zoey.test.Dao" targetProject="src/main/java">    
                <property name="enableSubPackages" value="true"/>    
            </javaClientGenerator> 

            <!-- 要生成的表tableName是資料庫中的表名和檢視名 domainobjectName是實體類名 -->
            <table tableName="user_t" domainObjectName="User"
             enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false"    
               enableSelectByExample="false" selectByExampleQueryId="false" >    
            <property name="useActualColumnNames" value="false"/>  
             </table>

        </context>

  </generatorConfiguration>

配置檔案中要注意的幾點：

1.驅動的地址，要注意，使用本地的jar包，所以需要絕對路徑
<classPathEntry location="C:/Users/witon/.m2/repository/org/postgresql/postgresql/9.4-1201-jdbc41/postgresql-9.4-1201-jdbc41.jar"></classPathEntry>

2.要注意生成的pojo的名稱domainObjectName屬性

第四步：執行mybatis-generator:generate命令

選擇專案，右鍵->Run As ->Maven Build->Goals輸入mybatis-generator:generate，點選apply，點選Run

結果：

[INFO] Scanning for projects...
[INFO] 
[INFO] Using the builder org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder with a thread count of 1
[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building SSMLTest Maven Webapp 0.0.1-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] --- mybatis-generator-maven-plugin:1.3.2:generate (default-cli) @ SSMLTest ---
[INFO] Connecting to the Database
[INFO] Introspecting table user_t
log4j:WARN No appenders could be found for logger (org.mybatis.generator.internal.db.DatabaseIntrospector).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
[INFO] Generating Record class for table user_t
[INFO] Generating Mapper Interface for table user_t
[INFO] Generating SQL Map for table user_t
[INFO] Saving file UserMapper.xml
[INFO] Saving file User.java
[INFO] Saving file UserMapper.java
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1.417 s
[INFO] Finished at: 2017-03-03T11:17:05+08:00
[INFO] Final Memory: 7M/116M
[INFO] ------------------------------------------------------------------------

為自己鼓掌，雖然中間出現好多問題，不過幸好都一一克服了！