问题描述
在同一个包下，我建立了两个Java文件(做Javabean的)，分别为UserBean.java和UserCheckBean.java。（UserCheckBean调用UserBean）先编译好UserBean成功后，再编译UserCheckBean.java时却出现cannotfindsymbol（UserBean）字样。后来，我没有按照先后顺序编译，而是直接Java*.java这样就都编译成功了。这是为什么呢？因为我的两个源码存在明显的先后关系（UserCheckBean调用UserBean），那为什么分开编译后就不可以了呢？？？？？谢谢UserBean.java代码：packagecom.itzcn.jack.chapter2;publicclassUserBean{privateStringname;privateStringpassword;publicStringgetName(){returnname;}publicvoidsetName(Stringname){this.name=name;}publicStringgetPassword(){returnpassword;}publicvoidsetPassword(Stringpassword){this.password=password;}}UserCheckBean.java代码：packagecom.itzcn.jack.chapter2;publicclassUserCheckBean{protectedUserBeanuser;publicUserCheckBean(){}publicUserCheckBean(UserBeanuser){this.user=user;}publicUserBeangetUser(){returnuser;}publicbooleancheckUser(){Stringname=user.getName();Stringpassword=user.getPassword();if(name.equals("赵兴")&&password.equals("123"))returntrue;elsereturnfalse;}}错误：UserCheckBean.java:4:cannotfindsymbolsymbol:classUserBeanlocation:classcom.itzcn.jack.chapter2.UserCheckBeanprotectedUserBeanuser;^UserCheckBean.java:8:cannotfindsymbolsymbol:classUserBeanlocation:classcom.itzcn.jack.chapter2.UserCheckBeanpublicUserCheckBean(UserBeanuser)^UserCheckBean.java:12:cannotfindsymbolsymbol:classUserBeanlocation:classcom.itzcn.jack.chapter2.UserCheckBeanpublicUserBeangetUser()^3errors
解决方案
解决方案二：
我的jdk版本是1.5的，是不是版本低了环境变量设置：.;D:Javajdk1.5.0libdt.jar;D:Javajdk1.5.0libtools.jar
解决方案三：
UserCheckBean.java中引用了UserBean，他们之间存在编译依赖关系，应该一起编译，编译器将处理它们之间的依赖关系。
解决方案四：
在同一个包下又写了个servletcheckUserServlet.java使用javac*.java编译报错：checkUserServlet.java:25:cannotfindsymbolsymbol:methodUserCheckBean(com.itzcn.jack.chapter2.UserBean)location:classcom.itzcn.jack.chapter2.checkUserServletUserCheckBeanucb=UserCheckBean(user);^1error代码如下：packagecom.itzcn.jack.chapter2;importjava.io.*;importjava.util.*;importjavax.servlet.*;importjavax.servlet.http.*;importjava.lang.*;publicclasscheckUserServletextendsHttpServlet{publicvoidservice(HttpServletRequestrequest,HttpServletResponseresponse)throwsServletException,IOException{request.setCharacterEncoding("GBK");response.setContentType("text/html;chart=GBL");Stringaction=request.getParameter("action");if(!isValidated(request)&&!("login".equals(action))){gotoPage("login1.html",request,response);return;}if("login".equals(action)){UserBeanuser=newUserBean();user.setName(request.getParameter("name"));user.setPassword(request.getParameter("password"));UserCheckBeanucb=UserCheckBean(user);if(ucb.checkUser()){HttpSessionsession=request.getSession();session.setAttribute("user",user);gotoPage("start.jsp",request,response);}elsegotoPage("error.jsp",request,response);}}privatebooleanisValidated(HttpServletRequestrequest){HttpSessionsession=request.getSession();if(session.getAttribute("user")!=null)returntrue;elsereturnfalse;}privatevoidgotoPage(StringtUrl,HttpServletRequestrequest,HttpServletResponseresponse)throwsServletException,IOException{RequestDispatcherrd=request.getRequestDispatcher(tUrl);rd.forward(request,response);}}
解决方案五：
if("login".equals(action)){UserBeanuser=newUserBean();user.setName(request.getParameter("name"));user.setPassword(request.getParameter("password"));UserCheckBeanucb=UserCheckBean(user);//1）1）这句你是想实例化一个UserCheckBean(user)，但你没有加new关键字，怎么可能成功UserCheckBeanucb=newUserCheckBean(user);