Created attachment 32888 [details]
Apache Tomcat_7.0.61 - Error report.html

I forgot to delete the last return "" statement, and JSP compile point error to line number #8 which is same as the last return statement.

Code:
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<%@ page pageEncoding='UTF-8' contentType='text/html'%>
<%@ page import = 'java.util.*' %>
<%!
String test ()
{
	List<Object> listObjectClasses = null;
	if (listObjectClasses==null || listObjectClasses.size()==0)
		return "";

	String sImageIconFile = null;
	for (Object objectClass : listObjectClasses)
	{
		//sImageIconFile = "active-directory-objectClass-" + (String)objectClass + ".png";
	}
	boolean isImageIconFileExist = false;
	if (! (sImageIconFile==null || sImageIconFile.isEmpty()))
	{
		sImageIconFile = "images/" + sImageIconFile;
		//File fileImageIcon = new File (application.getRealPath (sImageIconFile));
		//isImageIconFileExist = fileImageIcon.exists ();
	}
	return (sImageIconFile==null || sImageIconFile.isEmpty()) ? "" : "<img src='" + sImageIconFile + "'/>";
	return "";
		// This statement above will cause tomcat JDT compiler point error to line #8。 But if move this line into the above line, then compiler will point error to the right line number #23
}
%>
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JSP compile exception
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org.apache.jasper.JasperException: Unable to compile class for JSP: 

An error occurred at line: 8 in the jsp file: /test.jsp
Unreachable code
5: {
6: 	List<Object> listObjectClasses = null;
7: 	if (listObjectClasses==null || listObjectClasses.size()==0)
8: 		return "1";
9: 
10: 	String sImageIconFile = null;
11: 	for (Object objectClass : listObjectClasses)


Stacktrace:
	org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:103)
	org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:366)
	org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:485)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:379)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:354)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:341)
	org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:657)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:357)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:395)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:339)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
	org.apache.catalina.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:108)
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If I put the test() function into a .java file and use javac to compile it, javac will point error to right line number.
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$ javac Test.java 
Picked up _JAVA_OPTIONS: -Dawt.useSystemAAFontSettings=lcd
Test.java:24: 错误: 无法访问的语句
		return "";
		^
1 个错误
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