帮我看下这个简单的JSP问题 问题是什么呢? 另外a, b , c 都必须大于0 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 运行不了 会抛出错误 HTTP STATUS 500错误 HTTP Status 500 - --------------------------------------------------------------------------------type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception org.apache.jasper.JasperException: Unable to compile class for JSPAn error occurred at line: 32 in the jsp file: /lx.jspGenerated servlet error: [javac] Compiling 1 source fileC:\Tomcat 5.0\work\Catalina\localhost\lx\org\apache\jsp\lx_jsp.java:82: ??? > ????? java.lang.String,java.lang.Stringif(a+b>c&&a+c>b&&b+c>a) ^An error occurred at line: 32 in the jsp file: /lx.jspGenerated servlet error:C:\Tomcat 5.0\work\Catalina\localhost\lx\org\apache\jsp\lx_jsp.java:82: ??? > ????? java.lang.String,java.lang.Stringif(a+b>c&&a+c>b&&b+c>a) ^An error occurred at line: 32 in the jsp file: /lx.jspGenerated servlet error:C:\Tomcat 5.0\work\Catalina\localhost\lx\org\apache\jsp\lx_jsp.java:82: ??? > ????? java.lang.String,java.lang.Stringif(a+b>c&&a+c>b&&b+c>a) ^An error occurred at line: 32 in the jsp file: /lx.jspGenerated servlet error:C:\Tomcat 5.0\work\Catalina\localhost\lx\org\apache\jsp\lx_jsp.java:84: ??? / ????? java.lang.String,doubledouble p=(a+b+c)/2.0; ^An error occurred at line: 32 in the jsp file: /lx.jspGenerated servlet error:C:\Tomcat 5.0\work\Catalina\localhost\lx\org\apache\jsp\lx_jsp.java:85: ??? - ????? double,java.lang.Stringdouble mianji=Math.sqrt(p*(p-a)*(p-b)*(p-c)); ^An error occurred at line: 32 in the jsp file: /lx.jspGenerated servlet error:C:\Tomcat 5.0\work\Catalina\localhost\lx\org\apache\jsp\lx_jsp.java:85: ??? - ????? double,java.lang.Stringdouble mianji=Math.sqrt(p*(p-a)*(p-b)*(p-c)); ^An error occurred at line: 32 in the jsp file: /lx.jspGenerated servlet error:C:\Tomcat 5.0\work\Catalina\localhost\lx\org\apache\jsp\lx_jsp.java:85: ??? - ????? double,java.lang.Stringdouble mianji=Math.sqrt(p*(p-a)*(p-b)*(p-c)); ^7 ?? org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:127) org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:351) org.apache.jasper.compiler.Compiler.generateClass(Compiler.java:415) org.apache.jasper.compiler.Compiler.compile(Compiler.java:458) org.apache.jasper.compiler.Compiler.compile(Compiler.java:439) org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:553) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:291) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248) javax.servlet.http.HttpServlet.service(HttpServlet.java:856) 1、你的form没有指定提交目标,都不知道提交到哪去2、你的form里的数据都没提交,你的js就从request里取数据,肯定是取不到的,所以你js里的a\b\c都是NULL,既然是null,你直接进行转换处理,当然会出错所以你的JSP运行不了很正常 按照你的想法 你想用aa bb cc 进行计算。可是 你是用的 a b c 再一个 a b c 是 String if(a+b> c&&a+c> b&&b+c> a) { double p=(a+b+c)/2.0; double mianji=Math.sqrt(p*(p-a)*(p-b)*(p-c)); out.print("面积:"+mianji); } 改为if(aa+bb>cc && aa+cc>bb && bb+cc>aa) { double p=(aa+bb+cc)/2.0; double mianji=Math.sqrt(p*(p-aa)*(p-bb)*(p-cc)); out.print("面积:"+mianji); } 字符串怎么不能用来做运算. JAVA internet js在火狐浏览器上不能运行,请高手指点? 请教Java urlrewrite 把目录改变时,图片等..的地址出错! jsp... 我是初学者,请问各位要得到字符a在字符串中的位置用什么函数? gzip与Cache-Control的一些问题? xml菜鸟问题 SelectMethod=direct 和SelectMethod=cursor有什么区别啊? 请问谁可以帮我!!!! hibernate查询不出数据 JAVA网络编程编程书籍推荐? 在线等 关于JSP与数据库连接问题 一个下午了 请高手指点!!!
[javac] Compiling 1 source fileC:\Tomcat 5.0\work\Catalina\localhost\lx\org\apache\jsp\lx_jsp.java:82: ??? > ????? java.lang.String,java.lang.String
if(a+b>c&&a+c>b&&b+c>a)
^An error occurred at line: 32 in the jsp file: /lx.jspGenerated servlet error:
C:\Tomcat 5.0\work\Catalina\localhost\lx\org\apache\jsp\lx_jsp.java:82: ??? > ????? java.lang.String,java.lang.String
if(a+b>c&&a+c>b&&b+c>a)
^An error occurred at line: 32 in the jsp file: /lx.jspGenerated servlet error:
C:\Tomcat 5.0\work\Catalina\localhost\lx\org\apache\jsp\lx_jsp.java:82: ??? > ????? java.lang.String,java.lang.String
if(a+b>c&&a+c>b&&b+c>a)
^An error occurred at line: 32 in the jsp file: /lx.jspGenerated servlet error:
C:\Tomcat 5.0\work\Catalina\localhost\lx\org\apache\jsp\lx_jsp.java:84: ??? / ????? java.lang.String,double
double p=(a+b+c)/2.0;
^An error occurred at line: 32 in the jsp file: /lx.jspGenerated servlet error:
C:\Tomcat 5.0\work\Catalina\localhost\lx\org\apache\jsp\lx_jsp.java:85: ??? - ????? double,java.lang.String
double mianji=Math.sqrt(p*(p-a)*(p-b)*(p-c));
^An error occurred at line: 32 in the jsp file: /lx.jspGenerated servlet error:
C:\Tomcat 5.0\work\Catalina\localhost\lx\org\apache\jsp\lx_jsp.java:85: ??? - ????? double,java.lang.String
double mianji=Math.sqrt(p*(p-a)*(p-b)*(p-c));
^An error occurred at line: 32 in the jsp file: /lx.jspGenerated servlet error:
C:\Tomcat 5.0\work\Catalina\localhost\lx\org\apache\jsp\lx_jsp.java:85: ??? - ????? double,java.lang.String
double mianji=Math.sqrt(p*(p-a)*(p-b)*(p-c));
^
7 ??
org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:127)
org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:351)
org.apache.jasper.compiler.Compiler.generateClass(Compiler.java:415)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:458)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:439)
org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:553)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:291)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
2、你的form里的数据都没提交,你的js就从request里取数据,肯定是取不到的,所以你js里的a\b\c都是NULL,既然是null,你直接进行转换处理,当然会出错
所以你的JSP运行不了很正常
可是 你是用的 a b c
{
double p=(a+b+c)/2.0;
double mianji=Math.sqrt(p*(p-a)*(p-b)*(p-c));
out.print("面积:"+mianji);
}
改为
if(aa+bb>cc && aa+cc>bb && bb+cc>aa)
{
double p=(aa+bb+cc)/2.0;
double mianji=Math.sqrt(p*(p-aa)*(p-bb)*(p-cc));
out.print("面积:"+mianji);
} 字符串怎么不能用来做运算.