[groovy] Converting a string to int in Groovy

I have a String that represents an integer value and would like to convert it to an int. Is there a groovy equivalent of Java's Integer.parseInt(String)?

toInteger() method is available in groovy, you could use that.

Well, Groovy accepts the Java form just fine. If you are asking if there is a Groovier way, there is a way to go to Integer.

Both are shown here:

String s = "99"
assert 99 == Integer.parseInt(s)
Integer i = s as Integer
assert 99 == i

Several ways to do it, this one's my favorite:

def number = '123' as int

Several ways to achieve this. Examples are as below

a. return "22".toInteger()
b. if("22".isInteger()) return "22".toInteger()
c. return "22" as Integer()
d. return Integer.parseInt("22")

Hope this helps

The way to use should still be the toInteger(), because it is not really deprecated.

int value = '99'.toInteger()

The String version is deprecated, but the CharSequence is an Interface that a String implements. So, using a String is ok, because your code will still works even when the method will only work with CharSequence. Same goes for isInteger()

See this question for reference : How to convert a String to CharSequence?

I commented, because the notion of deprecated on this method got me confuse and I want to avoid that for other people.

The Simpler Way Of Converting A String To Integer In Groovy Is As Follows...

String aa="25"
int i= aa.toInteger()

Now "i" Holds The Integer Value.

def str = "32"

int num = str as Integer

also you can make static import

import static java.lang.Integer.parseInt as asInteger

and after this use

String s = "99"
asInteger(s)

I'm not sure if it was introduced in recent versions of groovy (initial answer is fairly old), but now you can use:

def num = mystring?.isInteger() ? mystring.toInteger() : null

or

def num = mystring?.isFloat() ? mystring.toFloat() : null

I recommend using floats or even doubles instead of integers in the case if the provided string is unreliable.

Here is the an other way. if you don't like exceptions.

def strnumber = "100"
def intValue = strnumber.isInteger() ?  (strnumber as int) : null

As an addendum to Don's answer, not only does groovy add a .toInteger() method to Strings, it also adds toBigDecimal(), toBigInteger(), toBoolean(), toCharacter(), toDouble(), toFloat(), toList(), and toLong().

In the same vein, groovy also adds is* eqivalents to all of those that return true if the String in question can be parsed into the format in question.

The relevant GDK page is here.

Groovy Style conversion:

Integer num = '589' as Integer

If you have request parameter:

Integer age = params.int('age')