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How to solve java.lang.NullPointerException error? [duplicate]

When I run my Java program, it gives me an error on this line

compiler.getTask(null, null, new DiagnosticCollector<JavaFileObject>(), null, null, compilationUnits);

Error I am getting is:

Exception in thread "main" java.lang.NullPointerException     at AnotherClassLoader.loadClass(test.java:58)     at test.main(test.java:30)     at Main.main(Main.java:68) 

Can you please tell me how can I solve this error?

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Justin k Avatar asked May 05 '12 18:05

Justin k


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2 Answers

A NullPointerException means that one of the variables you are passing is null, but the code tries to use it like it is not.

For example, If I do this:

Integer myInteger = null; int n = myInteger.intValue(); 

The code tries to grab the intValue of myInteger, but since it is null, it does not have one: a null pointer exception happens.

What this means is that your getTask method is expecting something that is not a null, but you are passing a null. Figure out what getTask needs and pass what it wants!

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Jeremy Avatar answered Sep 23 '22 10:09

Jeremy


This error occures when you try to refer to a null object instance. I can`t tell you what causes this error by your given information, but you can debug it easily in your IDE. I strongly recommend you that use exception handling to avoid unexpected program behavior.

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Ehsan Khodarahmi Avatar answered Sep 22 '22 10:09

Ehsan Khodarahmi