J2ME in a Nutshell

Name

Throwable

Synopsis

Throwable is the base class from which all Java exception types are derived. Throwable objects may be constructed with an associated message that provides diagnostic information relating to the cause of the exception. The message, if it is set, can be retrieved using the getMessage() method.

Throwable has two subclasses that are base classes for different types of exceptions. The Error class and its subclasses describe errors that application code is not expected to recover from. J2SE has a large number of error subclasses; however, the CLDC supports only two of them. The Exception class is the base class for exceptions that an application can recover from. Application code is required to declare any Exceptions that it throws. It must also catch those exceptions thrown by methods that it invokes, apart from RuntimeException and its subclasses.

A Throwable contains a stack backtrace that contains the method call stack at the point at which the exception was thrown. The stack trace may be printed using the printStackTrace() method. Unlike J2SE, the CLDC Throwable class does not include a stack trace when it is created and does not provide a fillInStackTrace() method to force the stack trace to be written to it on demand. The CLDC reference implementation virtual machine fills in the stack trace only when the exception is thrown.

public class Throwable {  
// Public Constructors
   public Throwable();  
   public Throwable( String message);   // Public Instance Methods ...