isEmpty Null 체크하기

 

 

String str1 = "JavaCodeGeeks isEmpty Example";
String str2 = "";
String str3 = " "; //this String is not considered as empty

      boolean check1 = str1.isEmpty(); 
      boolean check2 = str2.isEmpty();

      

System.out.println("Is str1 empty? The answer is: "+str1.isEmpty() );

System.out.println("Is str1 empty? The answer is: "+check1 );  

System.out.println("Is str2 empty? The answer is: "+str2.isEmpty() );

      System.out.println("Is str2 empty? The answer is: "+check2 );

      System.out.println("Is str3 empty? The answer is: "+str3.isEmpty() ); 

      System.out.println("Is str3 empty? The answer is: "+str3.trim().isEmpty() );

 

 

 

결과 :

 

Is str1 empty? The answer is: false Is str1 empty? The answer is: false Is str2 empty? The answer is: true Is str2 empty? The answer is: true Is str3 empty? The answer is: false Is str3 empty? The answer is: true