javaweb编程中常见的异常及处理方法.doc

1. 严重: Servlet.service() for servlet action threw exceptionjava.lang.IllegalArgumentException: argument type mismatch异常说明：参数类型不匹配原因：Struts框架中的ActionForm，主要有三大作用：给属性赋值,自动转型和数据的验证。其中，在数据类型的自动转换中，简化了程序员的代码量，但是，以Struts 1.2为例:ActionForm对java.util.Date类型的数据(但是默认有java.sql.Date)没提供转型。解决办法：1.Form中的日期类型使用String类型，在Action中自己处理类型转换（即在Action中对Form-POJO转换时手工处理）。2.Form中使用java.util.Date类型，自定义一个日期转换类DateConverter（需要实现Converter接口），然后在自定义的ActionServlet或者Action基类中注册DateConverter：ConvertUtils.register(new DateConverter(), Date.class)。方法二具体处理办法：1.先申明一个转换类package yg.util;import java.text.ParseException;import java.text.SimpleDateFormat;import java.util.Date;import mons.beanutils.ConversionException;import mons.beanutils.Converter;public class UtilDateConverter implements Converter Overridepublic Object convert(Class type, Object value) / TODO Auto-generated method stub System.out.println(UtilDateConverter.value= + value); if (value = null) return value; if (value instanceof Date) return value; Date d=null; if (value instanceof String) SimpleDateFormat sdf = new SimpleDateFormat(yyyy-MM-dd); try d = sdf.parse(String)value); catch (ParseException e) / TODO Auto-generated catch block e.printStackTrace(); return d;2.再使服务器启动设使给类注册进去方法1.使用servlet注册package yg.util;import java.util.Date;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import mons.beanutils.ConvertUtils;/* 注册java.util.date转换器* author Administrator*/public class UtilDateConverterInitWithServlet extends HttpServlet Overridepublic void init() throws ServletException System.out.println(UtilDateConverterInitWithServlet.init(); ConvertUtils.register(new UtilDateConverter(), Date.class);其中web.xml文件加上UtilDateConverterInitWithServletcom.bjsxt.struts.UtilDateConverterInitWithServlet3方法2.使用struts中的plug-in进行注册package yg.util;import java.util.Date;import javax.servlet.ServletException;import mons.beanutils.ConvertUtils;import org.apache.struts.action.ActionServlet;import org.apache.struts.action.PlugIn;import org.apache.struts.config.ModuleConfig;public class UtilDateConverterInitWithPlugin implements PlugIn public void destroy() public void init(ActionServlet servlet, ModuleConfig config) throws ServletException System.out.println(UtilDateConverterInitWithPlugin.init(); ConvertUtils.register(new UtilDateConverter(), Date.class);其中struts-config.xml文件加上2. 严重: Servlet.service() for servlet jsp threw exceptionorg.apache.jasper.JasperException: Unable to compile class for JSP: An error occurred at line: 22 in the generated java fileThe method getJspApplicationContext(ServletContext) is undefined for the type JspFactoryStacktrace:at piler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:92)at piler.ErrorDispatcher.javacError(ErrorDispatcher.java:330)at piler.JDTCompiler.generateClass(JDTCompiler.java:439)at piler.Cpile(Compiler.java:334)at piler.Cpile(Compiler.java:312)at piler.Cpile(Compiler.java:299)at org.apache.jasper.JspCompilationCpile(JspCompilationContext.java:586)at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:317)at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)at org.apache.catalina.core.ApplicationFilterCernalDoFilter(ApplicationFilterChain.java:290)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)at filter.MyFilter.doFilter(MyFilter.java:31)at org.apache.catalina.core.ApplicationFilterCernalDoFilter(ApplicationFilterChain.java:235)at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)at org.apache.coyote.http11.Http11Pcess(Http11Processor.java:849)at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHcess(Http11Protocol.java:583)at .JIoEndpoint$Worker.run(JIoEndpoint.java:454)at java.lang.Thread.run(Thread.java:619)2013-3-26 9:04:56 org.apache.catalina.core.ApplicationContext log信息: HTMLManager: init: Associated with Deployer Catalina:type=Deployer,host=localhost2013-3-26 9:04:56 org.apache.catalina.core.ApplicationContext