Different ways for String to Integer Conversions in Java
Given a String in Java, the task is to convert this String into Integer.
Examples:
Input: str = "1234"
Output: 1234
Input: str = "456"
Output: 456
- Convert using Integer.parseInt(String)
The Integer class has a static method that returns an integer object representing the specified String parameter.
Syntax :
public static int parseInt(String str) throws NumberFormatException
or
public static int parseInt(String str, int radix) throws NumberFormatException
Parameters:
- str: A string which needs to be converted to the integer. It can also have the first character as a minus sign ‘-‘ (‘\u002D’) or plus sign ‘+’ (‘\u002B’) to represent the sign of the number.
- radix: The radix used while the string is being parsed. This parameter is only specific to the second variant of the method.
Exceptions: NumberFormatException is thrown by this method if any of the following situations occurs:
For both the variants:
- String is null or of zero length
- The value represented by the string is not a value of type int
- Specifically for the parseInt(String s, int radix) variant of the function:
- The second argument radix is either smaller than Character.MIN_RADIX or larger than Character.MAX_RADIX
- Any character of the string is not a digit of the specified radix, except that the first character may be a minus sign ‘-‘ (‘\u002D’) or plus sign ‘+’ (‘\u002B’) provided that the string is longer than length 1
Example:
class GfG {
public static void main(String args[])
{
String str = "1234" ;
int num1 = Integer.parseInt(str);
System.out.println( "Integer using "
+ "first variant of"
+ " praseInt = "
+ num1);
int num2 = Integer.parseInt(str, 16 );
System.out.println( "Integer using "
+ "second (radix) variant"
+ " of praseInt = "
+ num2);
}
}
|
Output:
Integer using first variant of praseInt = 1234
Integer using second (radix) variant of praseInt = 4660
- Convert using Integer.valueOf(String)
Syntax:
public static Integer valueOf(String str)
Parameters: This method accepts single parameter str of String type that is to be parsed.
Return Value: The method returns an Integer object holding the value represented by the string argument.
Example:
class GfG {
public static void main(String args[])
{
String str = "1234" ;
int num1 = Integer.valueOf(str);
System.out.println( "Integer using"
+ " valueOf() = "
+ num1);
}
}
|
Output:
Integer using valueOf() = 1234
Last Updated :
29 May, 2019
Like Article
Save Article
Share your thoughts in the comments
Please Login to comment...