Description and Symptoms
java.lang.NullPointerException is a very common Java exception that you can face when developing pure Java, Java EE
applications or executing Java programs & games. Exception in
thread "main" java.lang.NullPointerException has been around since
early JDK days e.g. JDK 1.0.
Sample
Error
java.lang.NullPointerException
at
org.ph.javaee.training1.CallerClassA.doSomething(CallerClassA.java:27)
at
org.ph.javaee.training1.NoClassDefFoundErrorSimulator.main(NoClassDefFoundErrorSimulator.java:28)
Possible
Causes
- Java programming problem.
- Java software (applications, games...) bug.
Troubleshooting and solutions
- Stack trace and root cause analysis of the affected code. Extra logging and debugging is also recommended.
- Java code review and bug identification. Addition of proper NULL validation to prevent the problem at the first place.
- Patch installation of the affected Java software.
References and Case Studies
