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Exception handling is the process of responding to the occurrence, during computation, of ''exceptions'' – anomalous or exceptional conditions requiring special processing – often changing the normal flow of program execution. It is provided by specialized programming language constructs or computer hardware mechanisms. In general, an exception is ''handled'' (resolved) by saving the current state of execution in a predefined place and switching the execution to a specific subroutine known as an ''exception handler''. If exceptions are ''continuable'', the handler may later resume the execution at the original location using the saved information. For example, a floating point divide by zero exception will typically, by default, allow the program to be resumed, while an out of memory condition might not be resolvable transparently. Alternative approaches to exception handling in software are error checking, which maintains normal program flow with later explicit checks for contingencies reported using special return values or some auxiliary global variable such as C's or floating point status flags; or input validation to preemptively filter exceptional cases. Some programmers write software with error reporting features that collect details that may be helpful in fixing the problem, and display those details on the screen, or store them to a file such as a core dump, or in some cases an automatic error reporting system such as Windows Error Reporting can automatically phone home and email those details to the programmers. == Exception handling in hardware == Hardware exception mechanisms are processed by the CPU. It is intended to support error detection and redirects the program flow to error handling service routines. The state before the exception is saved on the stack. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Exception handling」の詳細全文を読む スポンサード リンク
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