Introduction to Programming

throw

The throw statement consists of the keyword throw and either a variable or value of a reference type java.lang.Throwable, or the null reference. Since all the exceptions are children of java.lang.Throwable, any of the following throw statements is correct:

throw new Exception("Something happened");Exception ex = new Exception("Something happened");throw ex;Throwable thr = new Exception("Something happened");throw thr;throw null;

If null is thrown, as it is in the last statement, then JVM converts it to a NullPointerException, so these two statements are equivalent:

throw null;throw new NullPointerException;

And, just to remind you, the package java.lang does not need to be imported. You can refer to any of the package java.lang members—interface ...