What are the differences between length and length () in Java?

The length is an instance variable of an array in Java whereas length() is a method of String class.

length

• An array is an object that holds a fixed number of values of the same type.
• The length variable in an array returns the length of an array i.e. a number of elements stored in an array.
• Once arrays are initialized, its length cannot be changed, so the length variable can directly be used to get the length of an array.
• The length variable is used only for an array.

Example

public class ArrayLengthTest {
   public static void main(String args[]) {
      int array[] = {1, 2, 3, 4, 5, 6, 7};
      System.out.println("Length of an array is: " + array.length);
   }
}

Output

Length of an array is: 7

length()

• The length() method is a static method of String class.
• The length() returns the length of a string object i.e. the number of characters stored in an object.
• String class uses this method because the length of a string can be modified using the various operations on an object.
• The String class internally uses a char[] array that it does not expose to the outside world.

Example

public class StringLengthMethodTest {
   public static void main(String args[]) {
      String str = "Welcome to Tutorials Point";
      System.out.println("Length of String using length() method is: " + str.length());
   }
}

Output

Length of String using length() method is: 26