java 自定义异常

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java 语言针对常见异常状况已事先定义了相应的导常类型，并在程序运行出错时由系统自动创建相应异常对象并进行抛出、捕获和处理，当然我们也可以自己定义新的异常类型并人工抛出异常对象

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自己定义的类

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@SuppressWarnings("serial")public class MyException extends Exception {private int exceptionType;public MyException(String message, int exceptionType) {super(message);this.exceptionType = exceptionType;}public int getExceptionType() {return exceptionType;}}

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测试类如下

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public class TestMyException {public int testNum(int age) throws MyException {if (age >= 100 || age <= 0) {throw new MyException("   age is: " + age + " age is between 0 and 100", 4);} else {return age;}}public static void main(String[] args) {TestMyException my = new TestMyException();try {my.testNum(123);} catch (MyException e) {System.out.println(e.getMessage() + " " + e.getExceptionType());}}}

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运行结果如下

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  age is: 123 age is between 0 and 100 4

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