HTTP Status 500 – Internal Server Error


Type Exception Report

Message An exception occurred processing [/index.jsp] at line [3]

Description The server encountered an unexpected condition that prevented it from fulfilling the request.

Exception

org.apache.jasper.JasperException: An exception occurred processing [/index.jsp] at line [3]

1: <%@ include file="header.jsp" %>
2: 
3: <b><%=usernames.get(uid - 1)%></b><br/>
4: User ID: <%=uid%><br/><br/>
5: 
6: 


Stacktrace:
	org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:593)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:482)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:386)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:330)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)

Root Cause

java.lang.IndexOutOfBoundsException: Index -2 out of bounds for length 787
	java.base/jdk.internal.util.Preconditions.outOfBounds(Preconditions.java:64)
	java.base/jdk.internal.util.Preconditions.outOfBoundsCheckIndex(Preconditions.java:70)
	java.base/jdk.internal.util.Preconditions.checkIndex(Preconditions.java:248)
	java.base/java.util.Objects.checkIndex(Objects.java:372)
	java.base/java.util.ArrayList.get(ArrayList.java:459)
	org.apache.jsp.index_jsp._jspService(index_jsp.java:348)
	org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:444)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:386)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:330)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)

Note The full stack trace of the root cause is available in the server logs.


Apache Tomcat/9.0.10