The java.lang.Math.ceil() returns the double value that is greater than or equal to the argument and is equal to the nearest mathematical integer.
Note:
- If the argument is Integer, then the result is Integer.
 - If the argument is NaN or an infinity or positive zero or negative zero, then the result is the same as the argument.
 - If the argument value is less than zero but greater than -1.0, then the result is negative zero.
 
Syntax:
public static double ceil(double a)
a : the argument whose ceil value is to be determinedReturns : This method returns the double value that is greater than or equal to the argument and is equal to the nearest mathematical integer.
Example 01:To show working of java.lang.Math.ceil() method.
java
// Java program to demonstrate working// of java.lang.Math.ceil() methodimport java.lang.Math;class Gfg {    // driver code    public static void main(String args[])    {        double a = 4.3;        double b = 1.0 / 0;        double c = 0.0;        double d = -0.0;        double e = -0.12;        System.out.println(Math.ceil(a));        // Input Infinity, Output Infinity        System.out.println(Math.ceil(b));        // Input Positive Zero, Output Positive Zero        System.out.println(Math.ceil(c));        // Input Negative Zero, Output Negative Zero        System.out.println(Math.ceil(d));        // Input  less than zero but greater than -1.0        // Output Negative zero        System.out.println(Math.ceil(e));    }} | 
Output:
5.0 Infinity 0.0 -0.0 -0.0
Example 02: To show the working of ceil() with a positive double value
Java
import java.io.*;class GFG {    public static void main (String[] args) {        double number = 3.5;        double result = Math.ceil(number);        System.out.println(result);  // Output: 4.0    }} | 
Output :
4.0
