java.lang.Object | +----java.lang.Throwable
public class Throwable
extends Object
implements Serializable
The Throwable class is the superclass of all errors and exceptions in the Java language. Only objects that are instances of this class (or of one of its subclasses) are thrown by the Java Virtual Machine or can be thrown by the Java throw statement. Similarly, only this class or one of its subclasses can be the argument type in a catch clause.
A Throwable class contains a snapshot of the execution stack of its thread at the time it was created. It can also contain a message string that gives more information about the error.
Here is one example of catching an exception:
try {
int a[] = new int[2];
a[4];
} catch (ArrayIndexOutOfBoundsException e) {
System.out.println("exception: " + e.getMessage());
e.printStackTrace();
}