Java String compareTo()

Syntax of compareTo()

The syntax of the compareTo() method is:

string.compareTo(String str)

Here, string is an object of the String class.

compareTo() Parameters

The compareTo() method takes a single parameter.

• str - the string to be compared

compareTo() Return Value

• returns 0 if the strings are equal
• returns a negative integer if the string comes before the str argument in the dictionary order
• returns a positive integer if the string comes after the str argument in the dictionary order

Example: Java String compareTo()

Here,

• str1 and str2 are equal. Hence, str1.compareTo(str2) returns 0.
• str1 comes before str3 in the dictionary order. Hence, str1.compareTo(str3) returns negative, and str3.compareTo(str1) returns positive.

Example 2: Check if Two Strings are Equal

Output

str1 and str2 are not equal

Example 3: compareTo() With Case

The compareTo() method takes the letter case (uppercase and lowercase) into consideration.

When "Learn Java" is compared to "learn Java", we do not get 0. It is because compareTo() takes the letter case into consideration.

Related Tutorial: Java String equals()