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# Integer reverseBytes() Method in Java

• Last Updated : 07 Jul, 2018

The java.lang.Integer.reverseBytes(int a) is a built-in method which returns the value obtained by reversing the order of the bytes in the two’s complement representation of the specified int value.

Syntax :

`public static int reverseBytes(int a)`

Parameter: The method takes one parameter a of integer type whose bytes are to be reversed.

Return Value: The method will return the value obtained by reversing the bytes in the specified int value.

Examples:

```Input: 75
Output: 1258291200
Explanation:
Consider an integer a = 75
Binary Representation = 1001011
Number of one bit = 4
After reversing the bytes we get = 1258291200

Input: -43
Output: -704643073
```

Below programs illustrate the java.lang.Integer.reverseBytes() method:
Program 1: For a positive number.

 `// Java program to illustrate the``// Java.lang.Integer.reverseBytes() method``import` `java.lang.*;`` ` `public` `class` `Geeks {`` ` `    ``public` `static` `void` `main(String[] args)``    ``{`` ` `        ``int` `a = ``61``;``        ``System.out.println(``" Integral Number = "` `+ a);`` ` `        ``// It will return the value obtained by reversing the bytes in the``        ``// specified int value``        ``System.out.println(``"After reversing the bytes we get = "` `+ ``        ``Integer.reverseBytes(a));``    ``}``}`
Output:
```Integral Number = 61
After reversing the bytes we get = 1023410176
```

Program 2: For a negative number.

 `// Java program to illustrate the``// Java.lang.Integer.reverseBytes() method``import` `java.lang.*;`` ` `public` `class` `Geeks {`` ` `    ``public` `static` `void` `main(String[] args)``    ``{`` ` `        ``int` `a = -``43``;``        ``System.out.println(``" Integral Number = "` `+ a);`` ` `        ``// It will return the value obtained by reversing the bytes in the``        ``// specified int value``        ``System.out.println(``"After reversing the bytes we get = "` `+ ``        ``Integer.reverseBytes(a));``    ``}``}`
Output:
```Integral Number = -43
After reversing the bytes we get = -704643073
```

Program 3: For a decimal value and string.
Note: It returns an error message when a decimal value and string is passed as an argument.

 `// Java program to illustrate the``// Java.lang.Integer.reverseBytes() method``import` `java.lang.*;`` ` `public` `class` `Geeks {`` ` `    ``public` `static` `void` `main(String[] args)``    ``{`` ` `        ``int` `a = ``37.81``;``        ``System.out.println(``" Integral Number = "` `+ a);``        ``// It will return the value obtained by reversing the bytes in the``        ``// specified int value``        ``System.out.println(``"After reversing the bytes we get = "` `+ ``        ``Integer.reverseBytes(a));`` ` `        ``a = ``"81"``; ``// compile time error will be generated``        ``System.out.println(``" Integral Number = "` `+ a);``        ``System.out.println(``"After reversing the bytes we get = "` `+ ``        ``Integer.reverseBytes(a));``    ``}``}`
Output:
```prog.java:9: error: incompatible types: possible lossy conversion from double to int
int a = 37.81;
^
prog.java:18: error: incompatible types: String cannot be converted to int
a = "81";
^
2 errors

```

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