AboutException.java package main; import javax.swing.*; public class AboutException { public static void main(String[] a) { int i=1, j=0, k; k=i/j; try { k = i/j; // Causes division-by-zero exception //throw new Exception("Hello.Exception!"); } catch ( ArithmeticException e) { System.out.println("被0除. "+ e.getMessage()); } catch (Exception e) { if (e instanceof ArithmeticException) System.out.println("被0除"); else { System.out.println(e.getMessage()); } } finally { JOptionPane.showConfirmDialog(null,"OK"); } } }
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CatchWho 。Java public class CatchWho { public static void main(String[] args) { try { try { throw new ArrayIndexOutOfBoundsException(); } catch(ArrayIndexOutOfBoundsException e) { System.out.println( "ArrayIndexOutOfBoundsException" + "/内层try-catch"); } throw new ArithmeticException(); } catch(ArithmeticException e) { System.out.println("发生ArithmeticException"); } catch(ArrayIndexOutOfBoundsException e) { System.out.println( "ArrayIndexOutOfBoundsException" + "/外层try-catch"); } }
CatchWho2。Java public class CatchWho2 { public static void main(String[] args) { try { try { throw new ArrayIndexOutOfBoundsException(); } catch(ArithmeticException e) { System.out.println( "ArrayIndexOutOfBoundsException" + "/内层try-catch"); } throw new ArithmeticException(); } catch(ArithmeticException e) { System.out.println("发生ArithmeticException"); } catch(ArrayIndexOutOfBoundsException e) { System.out.println( "ArrayIndexOutOfBoundsException" + "/外层try-catch"); } }
EmbededFinally。Java public class EmbededFinally { public static void main(String args[]) { int result; try { System.out.println("in Level 1"); try { System.out.println("in Level 2"); // result=100/0; //Level 2 try { System.out.println("in Level 3"); result=100/0; //Level 3 } catch (Exception e) { System.out.println("Level 3:" + e.getClass().toString()); } finally { System.out.println("In Level 3 finally"); } // result=100/0; //Level 2 } catch (Exception e) { System.out.println("Level 2:" + e.getClass().toString()); } finally { System.out.println("In Level 2 finally"); } // result = 100 / 0; //level 1 } catch (Exception e) { System.out.println("Level 1:" + e.getClass().toString()); } finally { . System.out.println("In Level 1 finally"); } } }
SystemExitAndFinally.java public class SystemExitAndFinally { public static void main(String[] args) { try{ System.out.println("in main"); throw new Exception("Exception is thrown in main"); //System.exit(0); } catch(Exception e) { System.out.println(e.getMessage()); System.exit(0); } finally { System.out.println("in finally"); } } }
PrintExpressionStack.java // UsingExceptions.java // Demonstrating the getMessage and printStackTrace // methods inherited into all exception classes. public class PrintExceptionStack { public static void main( String args[] ) { try { method1(); } catch ( Exception e ) { System.err.println( e.getMessage() + " " ); e.printStackTrace(); } } public static void method1() throws Exception { method2(); } public static void method2() throws Exception { method3(); } public static void method3() throws Exception { throw new Exception( "Exception thrown in method3" ); } }
ThrowMultiExceptionsDemo.java import java.io.*; public class ThrowMultiExceptionsDemo { public static void main(String[] args) { try { throwsTest(); } catch(IOException e) { System.out.println("捕捉异常"); } } private static void throwsTest() throws ArithmeticException,IOException { System.out.println("这只是一个测试"); // 程序处理过程假设发生异常 throw new IOException(); //throw new ArithmeticException(); } }
OverrideThrows.java import java.io.*; public class OverrideThrows { public void test()throws IOException { FileInputStream fis = new FileInputStream("a.txt"); } } class Sub extends OverrideThrows { //如果test方法声明抛出了比父类方法更大的异常,比如Exception //则代码将无法编译…… public void test() throws FileNotFoundException { //... } }
ExceptionLinkInRealWorld.java /** * 自定义的异常类 * @author JinXuLiang * */ class MyException extends Exception { public MyException(String Message) { super(Message); } public MyException(String message, Throwable cause) { super(message, cause); } public MyException( Throwable cause) { super(cause); } } public class ExceptionLinkInRealWorld { public static void main( String args[] ) { try { throwExceptionMethod(); //有可能抛出异常的方法调用 } catch ( MyException e ) { System.err.println( e.getMessage() ); System.err.println(e.getCause().getMessage()); } catch ( Exception e ) { System.err.println( "Exception handled in main" ); } doesNotThrowException(); //不抛出异常的方法调用 } public static void throwExceptionMethod() throws MyException { try { System.out.println( "Method throwException" ); throw new Exception("系统运行时引发的特定的异常"); // 产生了一个特定的异常 } catch( Exception e ) { System.err.println( "Exception handled in method throwException" ); //转换为一个自定义异常,再抛出 throw new MyException("在方法执行时出现异常",e); } finally { System.err.println( "Finally executed in throwException" ); } // any code here would not be reached } public static void doesNotThrowException() { try { System.out.println( "Method doesNotThrowException" ); } catch( Exception e ) { System.err.println( e.toString() ); } finally { System.err.println( "Finally executed in doesNotThrowException" ); } System.out.println( "End of method doesNotThrowException" ); } }