Try -Catch - Finally 流程

 

1)try中代码执行并返回：

public class TryCatchFinally {
	
	public static void main(String[] args){  
        System.out.println("return value of x:=" + inc());  
    }  
  
    public static int inc() {  
        int x;  
          
        try{  
        //normal process  
            System.out.println("normal process");     
            x=1;  
            return x;  
        }catch(Exception e){  
            //Exception Process  
            System.out.println("Catch Process");      
            x=2;  
            return x;  
        }finally{  
            //process that catch process can not be trigger   
            x=3;  
            System.out.println("Fianlly and x : =" + x);  
        }  
        
    } 
}

 

    返回结果：

    

normal process
Fianlly and x : =3
return value of x:=1

 2）执行Catch中代码并返回

public static void main(String[] args) {
		System.out.println("return value of x:=" + inc());
	}

	public static int inc() {
		int x;

		try {
			// normal process
			System.out.println("normal process");  
			x = 1;
			throw new Exception("error");
		} catch (Exception e) {
			// Exception Process
			System.out.println("Catch Process");      
			x = 2;
			return x;
		} finally {
			// process that catch process can not be trigger
			x = 3;
			System.out.println("Fianlly and x : =" + x);  
		}
	}

    执行结果：

    

normal process
Catch Process
Fianlly and x : =3
return value of x:=2

 3）抛出异常，不执行catch块，直接执行finally快

    

	public static void main(String[] args) throws Exception {
		System.out.println("return value of x:=" + inc());
	}

	public static int inc() throws Exception {
		int x;

		try {
			// normal process
			System.out.println("normal process");
			x = 1;
			throw new Exception("error");
		} catch (RuntimeException e) {
			// Exception Process
			System.out.println("Catch Process");    
			x = 2;
			return x;
		} finally {
			// process that catch process can not be trigger
			x = 3;
			System.out.println("Fianlly and x : =" + x);  
		}
	}

     结果：

     

normal process
Exception in thread "main" Fianlly and x : =3
java.lang.Exception: error
	at ClassStructure.TryCatchFinally.inc(TryCatchFinally.java:16)
	at ClassStructure.TryCatchFinally.main(TryCatchFinally.java:6)

   4）try-catch-finally执行之后x的值是多少

      

package ClassStructure;

public class TryCatchFinally {

	private static int x;

	public static void main(String[] args) {
		System.out.println("return value of x:=" + inc());
		System.out.println("process the method x : " + x);
	}

	public static int inc() {
		// int x;

		try {
			// normal process
			System.out.println("normal process");
			x = 1;
			return x;
		} catch (RuntimeException e) {
			// Exception Process
			System.out.println("Catch Process");
			x = 2;
			return x;
		} finally {
			// process that catch process can not be trigger
			x = 3;
			System.out.println("Fianlly and x : =" + x);
		}

	}
}

    执行结果：

    

normal process
Fianlly and x : =3
return value of x:=1
process the method x : 3