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1. RuntimeExceptionÓëException, Error²»Í¬µã£º µ±·½·¨ÌåÖÐÅ׳ö·ÇRuntimeException£¨¼°Æä×ÓÀࣩʱ£¬·½·¨Ãû±ØÐëÉùÃ÷Å׳öµÄÒì³££»µ«Êǵ±·½·¨ÌåÖÐÅ׳öRuntimeException£¨°üÀ¨RuntimeException×ÓÀࣩʱ£¬·½·¨Ãû²»±ØÉùÃ÷¸Ã¿ÉÄܱ»Å׳öµÄÒì³££¬¼´Ê¹ÉùÃ÷ÁË£¬JAVA³ÌÐòÔÚij¸öµ÷Óõĵط½£¬Ò²²»ÐèÒªtry-catch´Ó¾äÀ´´¦ÀíÒì³£¡£
class TestA{
//compiles fine.we don't need to claim the RuntimeException to be thrown here
void method(){
throw new RuntimeException();
}
}
class TestB{
void method() throws RuntimeException{
throw new RuntimeException();
}
void invokeMethod(){
//compiles fine. we don't need the try-catch clause here
method();
}
}
class TestC{
//compiles error.we need to claim the Exception to be thrown on the method name
void method(){
throw new Exception();
}
}
class TestD{
//compiles fine.
void method() throws Exception{
throw new Exception();
}
}
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2. ¼ÙÈçÒ»¸ö·½·¨ÔÚ¸¸ÀàÖÐûÓÐÉùÃ÷Å׳öÒì³££¬ÄÇô£¬×ÓÀา¸Ç¸Ã·½·¨µÄʱºò£¬²»ÄÜÉùÃ÷Òì³£¡£
class TestA{
void method(){}
}
class TestB extends TestA{
//complies error if the method overrided pertaining to the base class doesn't declare throwing exceptions
void method() throws Exception{
throw new Exception();
}
}
3. ¼ÙÈçÒ»¸ö·½·¨ÔÚ¸¸ÀàÖÐÉùÃ÷ÁËÅ׳öÒì³££¬×ÓÀา¸Ç¸Ã·½·¨µÄʱºò£¬ÒªÃ´²»ÉùÃ÷Å׳öÒì³££¬ÒªÃ´ÉùÃ÷±»Å׳öµÄÒì³£¼Ì³Ð×ÔËüËù¸²¸ÇµÄ¸¸ÀàÖеķ½·¨Å׳öµÄÒì³£¡£
class TestA{
void method() throws RuntimeException{}
}
class TestB extends TestA{
//compiles fine if current method does not throw any exceptions
void method(){}
}
class TestC extends TestA{
//compiles fine because NullPointerException is inherited from RuntimeException which is thrown by the overrided method of the base class
void method() throws NullPointerException{}
}
class TestD extends TestA{
//compiles error because Exception thrown by current method is not inherited from RuntimeException which is thr
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