关于try-catch、throw、finally在异常时的执行顺序

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package test;//jdk 1.8public class TestException1 {/** * catch中的return和throw是不能共存的(无论谁先谁后都编译不通过) * 如果只throw e，则必须try-catch捕捉异常e或用throws抛出异常e * 如果只return ，则在catch段正常返回值 */int testEx0(){boolean ret = true;try {int c = 12 / 0;System.out.println("testEx,successfully");return 0;} catch (Exception e) {System.out.println("testEx, catch exception");ret = false;return -1;throw e;}}/** * 在finally中的return和throw是不能共存的(无论谁先谁后都编译不通过) * 如果只throw e，则必须try-catch捕捉异常e或用throws抛出异常e * 如果只return ，则在catch段正常返回值 */int testEx00(){int  ret = 0;try {int c = 12 / 0;System.out.println("testEx,successfully");return ret;} catch (Exception e) {System.out.println("testEx, catch exception");ret = -1;}finally{ret = 1;System.out.println("testEx, finally; return value=" + ret);throw e;return ret;}}/** * 结果： testEx, catch exceptiontestEx, finally; return value=falsefalse结论：在finally里没有return的时候：先执行finally的语句，再执行catch的return */boolean testEx01(){boolean ret = true;try {int c = 12 / 0;System.out.println("testEx,successfully");return true;} catch (Exception e) {System.out.println("testEx, catch exception");ret = false;return ret;}finally{System.out.println("testEx, finally; return value=" + ret);}}/** * 结果： * testEx, catch exceptiontestEx, finally; return value=11结论：在finally里有return的时候：先执行finally的语句和return，忽略catch的return */int testEx02(){int ret = 0;try {int c = 12 / 0;System.out.println("testEx,successfully");return ret;} catch (Exception e) {ret = -1;System.out.println("testEx, catch exception");return ret;}finally{ret = 1;System.out.println("testEx, finally; return value=" + ret);return ret;}}/** * 编译能通过， * 但运行时抛异常（当然也没有返回值） * @return */boolean testEx03(){boolean ret = true;try {int c = 12 / 0;System.out.println("testEx,successfully");return true;} catch (Exception e) {System.out.println("testEx, catch exception");ret = false;throw e;}finally{System.out.println("testEx, finally; return value=" + ret);}}/** * 编译不能通过（必须加throws主动抛异常，或try-catch捕捉，） * 但运行时抛异常（当然也没有返回值） * @return * @throws Exception  */boolean testEx031(){boolean ret = true;try {int c = 12 / 0;System.out.println("testEx,successfully");return true;} catch (Exception e) {System.out.println("testEx, catch exception");ret = false;throw new Exception(e);}finally{System.out.println("testEx, finally; return value=" + ret);}}/** * 结果： * testEx, catch exceptiontestEx, finally; return value=11 结论：函数在finally里正常返回return的值，无异常，显然catch中的throw被忽略 */int testEx04(){int ret = 0;try {int c = 12 / 0;System.out.println("testEx,successfully");return ret;} catch (Exception e) {System.out.println("testEx, catch exception");ret = -1;throw e;}finally{ret = 1;System.out.println("testEx, finally; return value=" + ret);return ret;}}public static void main(String[] args) {try {System.out.println(new TestException1().testEx0());//System.out.println(new TestException1().testEx00());//System.out.println(new TestException1().testEx01());//System.out.println(new TestException1().testEx02());//System.out.println(new TestException1().testEx03());//System.out.println(new TestException1().testEx031());//System.out.println(new TestException1().testEx04());} catch (Exception e) {e.printStackTrace();}}}
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