Do one thing, the jsps are compiled into java servlets, so you can check the code and see at the appropriate line. The java files are I guess in work directory of tomcat.
Line of error
org.apache.jsp.index_jsp._jspInit(index_jsp.java:22)
Here is the file to look at.
index_jsp.java
solved getting org.apache.jasper.JasperException: java.lang.NullPointerException