An exception handler designed to handle a specific type of object may be pre-empted by another handler whose exception type is a superclass of that type. This happens if the exception handler for that exception type appears earlier in the list of exception handlers.

For example:

try {
my $result = $self->divide($value, 0);
# divide() throws DivideByZeroException
return $result;
}
catch MathException with {
my $ex = shift;
print "Error: Caught MathException occurred\n";
return;
}
catc h DivideByZeroException with {
my $ex = shift;
print "Error: Caught DivideByZeroException\n";
ret urn 0;
};

Only instances of the System.Exception classes, or classes derived from System.Exception. This is in sharp contrast with C++ where instances of almost any type can be thrown.

Answered by Raksha , an ibibo Master, at 8:21 AM on June 17, 2008

hello radhe Hi,

An exception handler designed to handle a specific type of object may be pre-empted by another handler whose exception type is a superclass of that type.

This happens if the exception handler for that exception type appears earlier in the list of exception handlers.

For example:

try {
my $result = $self->divide($value, 0);
# divide() throws DivideByZeroException
return $result;
}
catch MathException with {
my $ex = shift;
print "Error: Caught MathException occurred\n";
return;
}
catc h DivideByZeroException with {
my $ex = shift;
print "Error: Caught DivideByZeroException\n";
ret urn 0;
};

Only instances of the System.Exception classes, or classes derived from System.Exception.

This is in sharp contrast with C++ where instances of almost any type can be thrown

Answered by raj u , an ibibo Master, at 1:08 PM on June 04, 2008

Most programs throw and catch objects that derive from the Exception class. An Exception indicates that a problem occurred, but it is not a serious system problem. Most programs you write will throw and catch Exceptions as opposed to Errors.

The Java platform defines the many descendants of the Exception class. These descendants indicate various types of exceptions that can occur. For example, IllegalAccessException signals that a particular method could not be found, and NegativeArraySizeException indicates that a program attempted to create an array with a negative size.

One Exception subclass, RuntimeException, is reserved for exceptions that indicate incorrect use of an API. An example of a runtime exception is NullPointerException, which occurs when a method tries to access a member of an object through a null reference. The section Unchecked Exceptions — The Controversy discusses why most applications shouldn't throw runtime exceptions or subclass RuntimeException.

Answered by Romi , an ibibo Master, at 6:27 PM on June 03, 2008

Hi,

An exception handler designed to handle a specific type of object may be pre-empted by another handler whose exception type is a superclass of that type.

This happens if the exception handler for that exception type appears earlier in the list of exception handlers.

For example:

try {
my $result = $self->divide($value, 0);
# divide() throws DivideByZeroException
return $result;
}
catch MathException with {
my $ex = shift;
print "Error: Caught MathException occurred\n";
return;
}
catc h DivideByZeroException with {
my $ex = shift;
print "Error: Caught DivideByZeroException\n";
ret urn 0;
};

Only instances of the System.Exception classes, or classes derived from System.Exception.

This is in sharp contrast with C++ where instances of almost any type can be thrown.

Answered by Ajay Pal , an ibibo Master, at 2:54 PM on June 02, 2008

well Radhe, Most programs throw and catch objects that derive from the Exception class. An Exception indicates that a problem occurred, but it is not a serious system problem. Most programs you write will throw and catch Exceptions as opposed to Errors.

The Java platform defines the many descendants of the Exception class. These descendants indicate various types of exceptions that can occur. For example, IllegalAccessException signals that a particular method could not be found, and NegativeArraySizeException indicates that a program attempted to create an array with a negative size. Only instances of the System.Exception classes, or classes derived from System.Exception. This is in sharp contrast with C++ where instances of almost any type can be thrown.

Answered by satyaiitk , an ibibo Master, at 11:16 AM on June 02, 2008

well, Most programs throw and catch objects that derive from the Exception class. An Exception indicates that a problem occurred, but it is not a serious system problem. Most programs you write will throw and catch Exceptions as opposed to Errors.

An exception handler designed to handle a specific type of object may be pre-empted by another handler whose exception type is a superclass of that type. This happens if the exception handler for that exception type appears earlier in the list of exception handlers.

For example:

try {
my $result = $self->divide($value, 0);
# divide() throws DivideByZeroException
return $result;
}
catch MathException with {
my $ex = shift;
print "Error: Caught MathException occurred\n";
return;
}
catc h DivideByZeroException with {
my $ex = shift;
print "Error: Caught DivideByZeroException\n";
ret urn 0;
};

Only instances of the System.Exception classes, or classes derived from System.Exception. This is in sharp contrast with C++ where instances of almost any type can be thrown.

Answered by Saurabh , an ibibo Master, at 8:58 AM on June 02, 2008

An exception handler designed to handle a specific type of object may be pre-empted by another handler whose exception type is a superclass of that type. This happens if the exception handler for that exception type appears earlier in the list of exception handlers.

For example:

try {
my $result = $self->divide($value, 0);
# divide() throws DivideByZeroException
return $result;
}
catch MathException with {
my $ex = shift;
print "Error: Caught MathException occurred\n";
return;
}
catc h DivideByZeroException with {
my $ex = shift;
print "Error: Caught DivideByZeroException\n";
ret urn 0;
};

Only instances of the System.Exception classes, or classes derived from System.Exception. This is in sharp contrast with C++ where instances of almost any type can be thrown.

Answered by jaivir , an ibibo Master, at 8:11 AM on June 02, 2008

Most programs throw and catch objects that derive from the Exception class. An Exception indicates that a problem occurred, but it is not a serious system problem. Most programs you write will throw and catch Exceptions as opposed to Errors.

The Java platform defines the many descendants of the Exception class. These descendants indicate various types of exceptions that can occur. For example, IllegalAccessException signals that a particular method could not be found, and NegativeArraySizeException indicates that a program attempted to create an array with a negative size.

One Exception subclass, RuntimeException, is reserved for exceptions that indicate incorrect use of an API. An example of a runtime exception is NullPointerException, which occurs when a method tries to access a member of an object through a null reference. The section Unchecked Exceptions — The Controversy discusses why most applications shouldn't throw runtime exceptions or subclass RuntimeException.

Answered by Ram Singh , an ibibo Master, at 6:59 AM on June 02, 2008

Most programs throw and catch objects that derive from the Exception class. An Exception indicates that a problem occurred, but it is not a serious system problem. Most programs you write will throw and catch Exceptions as opposed to Errors.

The Java platform defines the many descendants of the Exception class. These descendants indicate various types of exceptions that can occur. For example, IllegalAccessException signals that a particular method could not be found, and NegativeArraySizeException indicates that a program attempted to create an array with a negative size.

One Exception subclass, RuntimeException, is reserved for exceptions that indicate incorrect use of an API. An example of a runtime exception is NullPointerException, which occurs when a method tries to access a member of an object through a null reference. The section Unchecked Exceptions — The Controversy discusses why most applications shouldn't throw runtime exceptions or subclass RuntimeException.

Answered by Anju Singh , an ibibo Master, at 6:11 AM on June 02, 2008

well;
An exception handler designed to handle a specific type of object may be pre-empted by another handler whose exception type is a superclass of that type. This happens if the exception handler for that exception type appears earlier in the list of exception handlers.

For example:

try {
my $result = $self->divide($value, 0);
# divide() throws DivideByZeroException
return $result;
}
catch MathException with {
my $ex = shift;
print "Error: Caught MathException occurred\n";
return;
}
catc h DivideByZeroException with {
my $ex = shift;
print "Error: Caught DivideByZeroException\n";
ret urn 0;
};

Only instances of the System.Exception classes, or classes derived from System.Exception. This is in sharp contrast with C++ where instances of almost any type can be thrown.

Answered by kishore , an ibibo Master, at 1:08 AM on June 02, 2008