开发常见异常

常见异常总结：

问题：IllegalAgumentExecption

  

问题：内存溢出异常

这个一般报【http-8080-3】之类的

1.在eclipse安装目录中将eclipse的启动参数调大一些：

 

-startup plugins/org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar --launcher.library plugins/org.eclipse.equinox.launcher.win32.win32.x86_64_1.1.300.v20150602-1417 -product org.eclipse.epp.package.jee.product --launcher.defaultAction openFile --launcher.XXMaxPermSize 512M -showsplash org.eclipse.platform --launcher.XXMaxPermSize 512m --launcher.defaultAction openFile --launcher.appendVmargs -vmargs -Dosgi.requiredJavaVersion=1.7 -Xms512m -Xmx1024m

 

 

问题：BeanDefinitionParsingException

org.springframework.beans.factory.parsing.BeanDefinitionParsingException: Configuration problem: Failed to import bean definitions from URL location [classpath:applicationContext-service.xml]

 

原因：applicationContext-service.xml没有加进去总的spring配置文件，或者名字写错，或者配置文件内部程序错误。

 

 

问题：There is no Action mapped for namespace

There is no Action mapped for namespace [/sysadmin] and action name [deptAction_list] associated with context path [/qb_web]. - [unknown location]

 

原因：struts.xml文件不在src下，或者编译后不在classes下；

或者struts.xml配置文件内部错误；

或者有其他的struts-xxx.xml没有include到struts.xml中；

或者action与spring整合的时候出错，一些UserServie没有在struts配置文件中，或者写错，导致找不见struts.xml；

或者请求路径出错。

 

问题：action本身就在值栈中，但action不在值栈的栈顶；

 

问题：classpath

Classpath只能用在spring中，

 

问题：重定向和转发

问题：hibernate子配置文件Dept.hbm.xml问题

<property name="name" column="NAME">property>

01.name属性出错

报错：

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory' defined in class path resource [applicationContext.xml]: Invocation of init method failed; nested exception is Caused by: org.hibernate.property.access.spi.PropertyAccessBuildingException: Could not locate field nor getter method for property named [com.my.qb.domain.Userinfo#ne]

02.column属性出错

不会报错，但是加载运行的时候不行，这个要特别注意。

03.package出错

 

<hibernate-mapping package="com.my.qb.domain">

报错：

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory' defined in class path resource [applicationContext.xml]: Invocation of init method failed; nested exception is org.hibernate.MappingException: class cn.itcast.jk.domain.Dept not found while looking for property: id   Caused by: org.hibernate.MappingException: class cn.itcast.jk.domain.Dept not found while looking for property: id   Caused by: org.hibernate.boot.registry.classloading.spi.ClassLoadingException: Unable to load class [cn.itcast.jk.domain.Dept] Caused by: java.lang.ClassNotFoundException: Could not load requested class : cn.other.jk.domain.Dept

 

问题:数据库属性设为非空，但是没有赋值

Struts Problem Report

Struts has detected an unhandled exception:

 

Messages: ORA-01400: ??? NULL ?? ("ITQB"."USER_P"."CREATE_TIME")

could not execute statement

could not execute statement; SQL [n/a]; constraint [null]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute statement

 

File: oracle/jdbc/driver/DatabaseError.java

Line number: 112

 

 

java.sql.SQLException: ORA-01400: ??? NULL ?? ("ITQB"."USER_P"."CREATE_TIME")

 

 

问题：

新建jsp页面老提示： Multiple annotations found at this line:   - The superclass "javax.servlet.http.HttpServlet" was not found on the Java   Build Path 解决步骤： 1、右键项目-build path 2、选择configure build path... 3、选择 Javabuild path 4、Add Library –> server Runtime -> Click Next 5、选择  Server runtime (我的是 Tomcat 7.0) –>完成