Jsp NULL pointer

Java. lang. nullPointerException at org. apache. jsp. index_jsp. _ jspInit (index_jsp.java: 22) may be caused by many reasons. The most important reason is that the jar package in your project conflicts with the jar package in release, many solutions are to delete the jsp-api.jar and servlet-api.jar in the project two jar packages, this solution is correct, but after deleting these two jar packages, may still have a problem, in this case, you need to carefully check the information in your project. classpath file, pay special attention to kind = "lib" is not to reference the jsp-api.jar and servlet-api.jar these two jar packages, may reference the jar package in tomcat, if you find this situation, the two lines must be deleted. Restart tomcat. It should be okay! The deletion and modification of jar files must be reflected in the. classpath file. Otherwise, the above problems may occur.