异常处理五个关键字:try,catch,finally,throw,throws
捕获异常
try、catch、finally
package oop.demo10; public class Outer { public static void main(String[] args) { int a = 1; int b =0; //捕获多个异常:范围从小到大 try {//try监控区域 System.out.println(a/b); } catch (Error e) {//catch(想要捕获的异常类型)捕获异常 System.out.println("Error"); } catch (Exception e) { System.out.println("Exception"); }catch (Throwable e) { System.out.println("Throwable"); }finally {//处理善后工作 System.out.println("finally"); } } }
选中代码:Ctrl+Alt+T快捷键
抛出异常
throw:一般用于方法中抛出异常
throws:在方法上抛出异常
package oop.demo10; public class Outer { public static void main(String[] args) { new Outer().test(1,0); } //假设方法中,处理不了这个异常。那就通过throws在方法上抛出异常 public void test(int a,int b) throws ArithmeticException{ if (b==0){ throw new ArithmeticException();//throw 主动抛出异常 }else{ System.out.println(a/b); } } }