在idea中用mybatis generator反向构建报空指针。

[午后慵懒咖啡]

问题情况：在idea中mybatis generator反向构建报空指针。

pom:
<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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.jcht</groupId>
<artifactId>ssm</artifactId>
<packaging>war</packaging>
<version>1.0-SNAPSHOT</version>
<name>ssm Maven Webapp</name>
<url>http://maven.apache.org</url>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<finalName>ssm</finalName>
<plugins>
<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>
</plugins>
</build>
</project>
generatorConfig.xml 用的本地的dtd文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE generatorConfiguration SYSTEM "file:///E:\program Files/mybatis-generator-config_1_0.dtd">
<generatorConfiguration>
<!--导入属性配置-->
<properties resource="generator.properties"></properties>
<!--指定特定数据库的jdbc驱动jar包的位置-->
<classPathEntry location="${jdbc.driverLocation}"/>
<context id="default" targetRuntime="MyBatis3">
<!-- optional，旨在创建class时，对注释进行控制 -->
<commentGenerator>
<property name="suppressDate" value="true"/>
<property name="suppressAllComments" value="true"/>
</commentGenerator>
<!--jdbc的数据库连接 -->
<jdbcConnection
driverClass="${jdbc.driverClass}"
connectionURL="${jdbc.connectionURL}"
userId="${jdbc.userId}"
password="${jdbc.password}">
</jdbcConnection>
<!-- 非必需，类型处理器，在数据库类型和java类型之间的转换控制-->
<!-- 默认false，把JDBC DECIMAL 和 NUMERIC 类型解析为 Integer
true，把JDBC DECIMAL 和 NUMERIC 类型解析为java.math.BigDecimal
-->
<javaTypeResolver>
<property name="forceBigDecimals" value="false"/>
</javaTypeResolver>
<javaModelGenerator targetPackage="com.jcht.ssm.model"
targetProject="src/main/java">
<!-- 是否允许子包，即targetPackage.schemaName.tableName -->
<property name="enableSubPackages" value="false"/>
<!-- 是否对model添加 构造函数 -->
<property name="constructorBased" value="true"/>
<!-- 是否对类CHAR类型的列的数据进行trim操作 -->
<property name="trimStrings" value="true"/>
<!-- 建立的Model对象是否 不可改变 即生成的Model对象不会有 setter方法，只有构造方法 -->
<property name="immutable" value="false"/>
</javaModelGenerator>
<!--Mapper映射文件生成所在的目录 为每一个数据库的表生成对应的SqlMap文件 -->
<sqlMapGenerator targetPackage="com.jcht.ssm.mapper"
targetProject="src/main/java">
<property name="enableSubPackages" value="false"/>
</sqlMapGenerator>
<!-- 客户端代码，生成易于使用的针对Model对象和XML配置文件 的代码
type="ANNOTATEDMAPPER",生成Java Model 和基于注解的Mapper对象
type="MIXEDMAPPER",生成基于注解的Java Model 和相应的Mapper对象
type="XMLMAPPER",生成SQLMap XML文件和独立的Mapper接口
-->
<javaClientGenerator targetPackage="com.jcht.ssm.dao"
targetProject="src/main/java" type="XMLMAPPER">
<property name="enableSubPackages" value="true"/>
</javaClientGenerator>
<table tableName="dept" domainObjectName="Depatement"
enableCountByExample="true" enableUpdateByExample="false"
enableDeleteByExample="false" enableSelectByExample="false"
selectByExampleQueryId="true">
</table>
<table tableName="emp" domainObjectName="Employee"
enableCountByExample="false" enableUpdateByExample="false"
enableDeleteByExample="false" enableSelectByExample="false"
selectByExampleQueryId="false">
</table>
</context>
</generatorConfiguration>

generator.properties

jdbc.driverLocation= E:\\program Files\\mysql-connector-java-5.1.32.jar
jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.connectionURL=jdbc:mysql://localhost:3306/demo?useUnicode=true&characterEncoding=utf-8&zeroDateTimeBehavior=convertToNull
jdbc.userId=root
jdbc.password=123456
错误信息

"C:\Program Files\Java\jdk1.8.0_141\bin\java" -Dmaven.multiModuleProjectDirectory=F:\JetBrains\IdeaProjects\Demo\ssm "-Dmaven.home=E:\program Files\maven\apache-maven-3.3.9" "-Dclassworlds.conf=E:\program Files\maven\apache-maven-3.3.9\bin\m2.conf" "-javaagent:E:\program Files\programs\JetBrains\IntelliJ IDEA 2017.2\lib\idea_rt.jar=56954:E:\program Files\programs\JetBrains\IntelliJ IDEA 2017.2\bin" -Dfile.encoding=UTF-8 -classpath "E:\program Files\maven\apache-maven-3.3.9\boot\plexus-classworlds-2.5.2.jar" org.codehaus.classworlds.Launcher -Didea.version=2017.2 -s "E:\program Files\maven\apache-maven-3.3.9\conf\settings.xml" "-Dmaven.repo.local=E:\program Files\maven\repository" mybatis-generator:generate -e
[INFO] Error stacktraces are turned on.
[INFO] Scanning for projects...
[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building ssm Maven Webapp 1.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] --- mybatis-generator-maven-plugin:1.3.2:generate (default-cli) @ ssm ---
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2.130 s
[INFO] Finished at: 2017-07-23T23:07:43+08:00
[INFO] Final Memory: 7M/155M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate (default-cli) on project ssm: Execution default-cli of goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate failed. NullPointerException -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate (default-cli) on project ssm: Execution default-cli of goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate failed.
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:212)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:116)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:80)
    at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:307)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:193)
    at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:106)
    at org.apache.maven.cli.MavenCli.execute(MavenCli.java:863)
    at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:288)
    at org.apache.maven.cli.MavenCli.main(MavenCli.java:199)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
    at org.codehaus.classworlds.Launcher.main(Launcher.java:47)
Caused by: org.apache.maven.plugin.PluginExecutionException: Execution default-cli of goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate failed.
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:145)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:207)
    ... 21 more
Caused by: java.lang.NullPointerException
    at org.mybatis.generator.config.xml.ConfigurationParser.parseConfiguration(ConfigurationParser.java:127)
    at org.mybatis.generator.config.xml.ConfigurationParser.parseConfiguration(ConfigurationParser.java:82)
    at org.mybatis.generator.config.xml.ConfigurationParser.parseConfiguration(ConfigurationParser.java:74)
    at org.mybatis.generator.maven.MyBatisGeneratorMojo.execute(MyBatisGeneratorMojo.java:196)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:134)
    ... 22 more
[ERROR] 
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/PluginExecutionException

Process finished with exit code 1
有知道的么，需要你们的帮助啊

[午后慵懒咖啡]

今天早上在公司解决了，还是dtd的问题，当时糊涂了

[RobinsonLuo]

什么玩意？ dtd? 唉

[RobinsonLuo]

我的是postgresql.jar包问题，所有其他都检测了,最后实在没办法尝试换jar包才好的； 非常很神奇的是： 我原来已经用postgresql.jar这个包生成很多mapper了； 但过了几天再次使用反向工程生成mapper报错和楼主一样； 最后实在没办法，碰运气换了个jar包；postgresql-42.2.12.jar 解决。