Java String compareTo() Method

compareTo() method is used to compare the two specified Strings based on the alphabetical order(lexicographical order) of their characters.It returns positive number ,negative number or 0 Syntax:

public int compareTo(String anotherString)

Parameters: anotherString: the String to be compared with the current String Returns: An integer value based on the case. compare two Strings i.e. s1 and s2 if s1 > s2, it returns positive number if s1 < s2, it returns negative number if s1 == s2, it returns 0 Java String compareTo() Example 1:

public class CompareToEx1
{ 
public static void main(String args[]){ 
         String s1="tutorial"; 
         String s2="Tutorial"; 
         String s3="tootorial"; 
         String s4="tutorial"; 
        String s5="tooturial"; 
       System.out.println(s1.compareTo(s2));
       System.out.println(s1.compareTo(s3));
       System.out.println(s1.compareTo(s4));//0 because both are equal    
      System.out.println(s1.compareTo(s5));
}
}

Output:

32
6
0
6

Java String compareTo() Example 2:

public class CompareToEx2
{
    public static void main(String[] args)
    {
        //compare a String
        String str = "Java TutorialAndExample";
        System.out.println("Compare To : " + str.compareTo("JAVA TUTORIALANDEXAMPLE"));
        //Compare a String with Ignore case
        System.out.println("Compare To : " + str.compareToIgnoreCase("JAVA TUTORIALANDEXAMPLE"));
    }
}

OUTPUT:

Compare To : 32
Compare To : 0

Java String compareTo() Example 3:

public class CompareToEx3 {
    public static void main(String[] args) {
        String s1,s2,s3,s4;
         s1 = "tutorial";
         s2 = "tutorial2";
         s3 = "TUTORIAL";
        System.out.println("String 1: " + s1);
        System.out.println("String 2: " + s2);
        System.out.println("String 3: " + s3);        
        // Compare the strings s1 and s2.  
        int S = s1.compareTo(s2);
        // Show the results of the comparison.  
        if (S < 0) { 
             System.out.println(s1 +"  is lexicographically greater than  " +  s2 );
          //compare the string s1 and s3 
           int s = s1.compareTo(s3.toLowerCase());
             if (s < 0) { 
             System.out.println( s1 +  " is lexicographically greater than " + s3 );
            } else if (s == 0) {
            System.out.println(s1 + " is lexicographically  equal to " + s3 );
        } else if (s > 0) {
            System.out.println( s1 + " is lexicographically less than " + s3 );
        } 
          } else if (S == 0) {
            System.out.println(s1 + " is lexicographically  equal to " +  s2 );
        } else if (S > 0) {
            System.out.println( s1 + " is lexicographically less than " +  s2 );
        } 
  }

Output:

String 1: tutorial
String 2: tutorial2
String 3: TUTORIAL
"tutorial" is lexicographically greater than "tutorial2"
"tutorial" is lexicographically  equal to "TUTORIAL"