打印 Hello World!

题目：在if()里添加任意代码 使之打印出 Hello World!

 

public static void main(String[] args){  
		try { 
			if(){  
				System.out.print("Hello ");  
			}else{  
				System.out.println("world!");  
            }  
         } catch (Exception e) {  
            e.printStackTrace();  
        }   
	}  
 

 

(一)匿名类

解答1（qrh's idea）

if(new Callable<Boolean>() {
    public Boolean call() {
        System.out.print("Hello ");  
        return false;
    }
}.call()){  
    System.out.print("Hello ");  
}else{  
    System.out.println("world!");  
}  

 

解答2

if(new Object(){{System.out.print("Hello ");}} == null){  
    System.out.print("Hello ");  
}else{  
    System.out.println("world!");  
}  

 

 

解答3

if(true)System.out.print("Hello "); if(false){    
     System.out.print("Hello ");    
}else{    
    System.out.println("world!");    
}    

 

解答4

if (System.out.append("Hello ")== null) {  
    System.out.print("Hello ");  
} else {  
     System.out.println("world!");  
} 

 

  （三）反射

解答5

if(System.out.getClass().getDeclaredMethod("print", String.class).invoke(System.out, "Hello ") == null){  
	System.out.print("Hello ");  
}else{  
	System.out.println("world!");  
}