The java.lang.Long.compareTo() is a built-in method in java that compares two Long objects numerically. This method returns 0 if this object is equal to the argument object, it returns less than 0 if this object is numerically less than the argument object and a value greater than 0 if this object is numerically greater than the argument object.
Syntax:
public int compareTo(Object obj) Parameter: obj - The object which is to be compared to.
Returns: The function returns three values:
- equal to 0: Object is equal to the argument object
- less than 0: Object is less than the argument object
- greater than 0: Object is greater than the argument object
Program 1: The program below demonstrates the working of function.
// Java program to demonstrate// of java.lang.Long.compareTo() methodimport java.lang.Math;  class Gfg1 {      // driver code    public static void main(String args[])    {          // when two objects are different        Long obj1 = new Long(124);        Long obj2 = new Long(167);        int compareValue = obj1.compareTo(obj2);          if (compareValue == 0)            System.out.println("object1 and object2 are equal");        else if (compareValue < 0)            System.out.println("object1 is less than object2");        else            System.out.println("object1 is greater than object2");    }} |
Output:
object1 is less than object2
Program 2: The program below demonstrates the working of function when no argument is passed
// Java program to demonstrate// of java.lang.Long.compareTo() methodimport java.lang.Math;  class Gfg1 {      // driver code    public static void main(String args[])    {        // when no argument is passed        Long obj1 = new Long(124);        Long obj2 = new Long(167);          int compareValue = obj1.compareTo();          if (compareValue == 0)            System.out.println("object1 and object2 are equal");        else if (compareValue < 0)            System.out.println("object1 is less than object2");        else            System.out.println("object1 is greater than object2");    }} |
Output:
prog.java:14: error: method compareTo in class Long cannot be applied to given types;
int compareValue = obj1.compareTo();
^
required: Long
found: no arguments
reason: actual and formal argument lists differ in length
1 error
Program 3: The program below demonstrates the working of function when anything other than object is passed in an argument
// Java program to demonstrate// of java.lang.Long.compareTo() methodimport java.lang.Math;  class Gfg1 {      // driver code    public static void main(String args[])    {          // when anything other than object        // argument is passed        Long obj1 = new Long(124);          int compareValue = obj1.compareTo("gfg");          if (compareValue == 0)            System.out.println("object1 and object2 are equal");        else if (compareValue < 0)            System.out.println("object1 is less than object2");        else            System.out.println("object1 is greater than object2");    }} |
Output:
prog.java:14: error: incompatible types: String cannot be converted to Long
int compareValue = obj1.compareTo("gfg");
^
Note: Some messages have been simplified; recompile with -Xdiags:verbose to get full output
1 error
