Learn what causes null pointer exceptions in Java, how to identify them, and how to fix them with simple techniques and best practices. Also, learn how to test and learn more about them.

Ever come across the null pointer exception in Java? We explain what this error message means, why it happens, and how to avoid the billion-dollar mistake.

Null pointer exception is a commonly occurring error in Java programs, and many static analysis tools can identify such errors. However, most of existing tools ...