Groovy map syntax error

If I have this code :

import javax.swing.*
import java.awt.image.*

def xMap = [
    BufferedImage.TYPE_3BYTE_BGR     : "3 byte BGR",
    BufferedImage.TYPE_4BYTE_ABGR    : "4 byte ABGR",
]

the IDE will generate this error :

illegal colon after argument expression;
   solution: a complex label expression before a colon must be parenthesized at

Is there another solution to this than to write :

def type_3byte_bgr = BufferedImage.TYPE_3BYTE_BGR

for all the constants?