1、在if括號填入boolean表示式

public class TestBoolean {
	public static void main(String[] args){
	      int x = 100;
	      if( x < 200 ){ 
	         System.out.print("boolean測試");
	      }
	   }
}

2、在if括號填入boolean型別

public class TestBoolean {
	public static void main(String[] args){
	      int x = 100;
	      if(true){ 
	         System.out.print("boolean測試");
	      }
	   }
}
 

3、邏輯運算

public static void main(String[] args){
		 if((10 > 5) && (19 > 6)){ //全部條件為true執行
	         System.out.print("&&");
	      }
	   }

public static void main(String[] args){
		 if((10 > 5) || (19 < 6)){ //其中一個為true執行
	         System.out.print("||");
	      }
	   }
 

4、if/else語句

public static void main(String[] args){
		int x = 10;
	      if( x < 20 ){
	         System.out.print("這是 if 語句");
	      }else{
	         System.out.print("這是 else 語句");
	      }
	}

public static void main(String[] args){
		  int x = 10;
	      if( x == 10 ){
	         System.out.print("Value of X is 10");
	      }else if( x == 10 ){
	         System.out.print("Value of X is 20");
	      }else if( x == 30 ){
	         System.out.print("Value of X is 30");
	      }else{
	         System.out.print("這是 else 語句");
	      }
	}