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Comment: Migrated to Confluence 4.0

Groovy's static import capability allows you to reference imported classes as if they were static methods in your own class. This is similar to Java's static import capability but works with Java 1.4 and above and is a little more dynamic than Java in that it allows you to define methods with the same name as an imported method as long as you have different types. If you have the same types, the imported class takes precedence. Here is a sample of its usage:

Code Block
import static java.awt.Color.LIGHT_GRAY
import static Boolean.FALSE as F
import static Calendar.getInstance as now
import static Integer.*

println LIGHT_GRAY
// => java.awt.Color[r=192,g=192,b=192]

println !F
// => true

println now().time
// => Sun Apr 29 11:12:43 EST 2007

println "Integers are between $MIN_VALUE and $MAX_VALUE"
// => Integers are between -2147483648 and 2147483647

def toHexString(int val, boolean upperCase) {
    def hexval = upperCase ? toHexString(val).toUpperCase() : toHexString(val)
    return '0x' + hexval
println toHexString(15, true)
// => 0xF
println toHexString(15, false)
// => 0xf

The first static import illustrates defining LIGHT_GRAY as if it was defined locally as a static field.
The next two examples show renaming (called aliasing) of a field and a method respectively.
The final example illustrates wild-carding for fields and methods and also selecting between the locally defined toHexString and imported toHexString based on parameter matching.

As another example, here is how to statically import some of the Math functions:

Code Block
import static java.lang.Math.*
println sin(123.456) * cos(456.789)
// => 0.24733809349262376