Exceptions - Java Software Solutions: Foundations of Program Design - page 579

Summary of Key Concepts

Errors and exceptions are objects that represent unusual or invalid
processing.

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The messages printed when an exception is thrown provide a method call
stack trace.

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Each catch clause handles a particular kind of exception that may be
thrown within the try block.

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The finally clause is executed whether the try block is exited normally
or because of a thrown exception.

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If an exception is not caught and handled where it occurs, it is propagated
to the calling method.

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A programmer must carefully consider how and where exceptions should
be handled, if at all.

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A new exception is defined by deriving a new class from the Exception
class or one of its descendants.

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The throws clause on a method header must be included for checked
exceptions that are not caught and handled in the method.

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A stream is a sequential sequence of bytes; it can be used as a source of
input or a destination for output.

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Three public reference variables in the System class represent the standard
I/O streams.

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Output file streams should be explicitly closed or they may not correctly
retain the data written to them.

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The Java class library contains many classes for defining I/O streams with
various characteristics.

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Tool tips and mnemonics can enhance the functionality of a graphical user
interface.

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Components should be disabled when their use is inappropriate.

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A combo box provides a drop down menu of options for the user.

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A scroll pane is useful for viewing large objects or large amounts of data.

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A split pane displays two components side by side or one on top of the
other.

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