spring mybatis with external jar dao答案

【问题标题】：spring mybatis with external jar daospring mybatis with external jar dao
【发布时间】：2015-10-29 13:25:10
【问题描述】：

我正在开发两个 Spring-Mybatis 项目，它们需要相同的 DAO 类，因为它们连接到同一个数据库。

我为 DAO 类生成了 jar 并将其放入类路径中。

但是 Mybatis 找不到类，因为 Tomcat 和 Spring 在 Mybatis 的初始化生命周期中还没有加载 DAO jar。

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in ServletContext resource [/WEB-INF/database-context.xml]: Invocation of init method failed; nested exception is org.springframework.core.NestedIOException: Failed to parse config resource: class path resource [com/test/ca/mybatis-config.xml]; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing SQL Mapper Configuration. Cause: org.apache.ibatis.builder.BuilderException: Error registering typeAlias for 'AgentInfo'. Cause: java.lang.ClassNotFoundException: Cannot find class: com.test.ca.domain.AgentInfo
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1512)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:521)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:296)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:293)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:610)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:932)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:479)
    at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:410)
    at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306)
    at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:112)
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:5017)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5531)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1574)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1564)
    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
    at java.util.concurrent.FutureTask.run(FutureTask.java:166)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:724)
Caused by: org.springframework.core.NestedIOException: Failed to parse config resource: class path resource [com/test/ca/mybatis-config.xml]; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing SQL Mapper Configuration. Cause: org.apache.ibatis.builder.BuilderException: Error registering typeAlias for 'AgentInfo'. Cause: java.lang.ClassNotFoundException: Cannot find class: com.test.ca.domain.AgentInfo
    at org.mybatis.spring.SqlSessionFactoryBean.buildSqlSessionFactory(SqlSessionFactoryBean.java:434)
    at org.mybatis.spring.SqlSessionFactoryBean.afterPropertiesSet(SqlSessionFactoryBean.java:340)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1571)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1509)
    ... 22 more
Caused by: org.apache.ibatis.builder.BuilderException: Error parsing SQL Mapper Configuration. Cause: org.apache.ibatis.builder.BuilderException: Error registering typeAlias for 'AgentInfo'. Cause: java.lang.ClassNotFoundException: Cannot find class: com.test.ca.domain.AgentInfo
    at org.apache.ibatis.builder.xml.XMLConfigBuilder.parseConfiguration(XMLConfigBuilder.java:106)
    at org.apache.ibatis.builder.xml.XMLConfigBuilder.parse(XMLConfigBuilder.java:89)
    at org.mybatis.spring.SqlSessionFactoryBean.buildSqlSessionFactory(SqlSessionFactoryBean.java:428)
    ... 25 more
Caused by: org.apache.ibatis.builder.BuilderException: Error registering typeAlias for 'AgentInfo'. Cause: java.lang.ClassNotFoundException: Cannot find class: com.test.ca.domain.AgentInfo
    at org.apache.ibatis.builder.xml.XMLConfigBuilder.typeAliasesElement(XMLConfigBuilder.java:127)
    at org.apache.ibatis.builder.xml.XMLConfigBuilder.parseConfiguration(XMLConfigBuilder.java:96)
    ... 27 more
Caused by: java.lang.ClassNotFoundException: Cannot find class: com.test.ca.domain.AgentInfo
    at org.apache.ibatis.io.ClassLoaderWrapper.classForName(ClassLoaderWrapper.java:188)
    at org.apache.ibatis.io.ClassLoaderWrapper.classForName(ClassLoaderWrapper.java:87)
    at org.apache.ibatis.io.Resources.classForName(Resources.java:254)
    at org.apache.ibatis.builder.xml.XMLConfigBuilder.typeAliasesElement(XMLConfigBuilder.java:120)

所以我把jar放在tomcat/lib文件夹下，但是为了避免ClassNotFoundException，我需要把所有的依赖jar都添加到这个文件夹中。

我正在尝试这个，因为我不想两次创建相同的 DAO 类。

谁能帮帮我？

【问题讨论】：

您需要澄清您的问题。现在太宽泛了。

标签： java spring tomcat jvm mybatis

【解决方案1】：

将所有依赖 jar 放入项目中是非常繁琐的。

我建议你将 maven 集成到你现有的项目中，并依赖你的 dao jar。

如果你的 dao jar 依赖于其他一些类，maven 会为你下载它。

【讨论】：