Re: Creating a array class for a given class name

From:

Piotr Kobzda <pikob@gazeta.pl>

Newsgroups:

comp.lang.java.help

Date:

Sat, 28 Jun 2008 12:59:39 +0200

Message-ID:

<g455jg$kpu$1@inews.gazeta.pl>

Patricia Shanahan wrote:

I think this may work:

Class.forName("[L"+className+";");

For more dimensions, add leading "[" symbols. This calls forName on
the string that the array's class object's getName() returns.

And here is a bit extended use of your advice:

public class ArrayUtil {

     public static Class<?> arrayType(Class<?> componentType, int dims)
             throws ClassNotFoundException {
         char[] da = new char[dims];
         java.util.Arrays.fill(da, '[');
         return Class.forName(
                 new String(da) + nativeTypeDescriptor(componentType),
                 false, componentType.getClassLoader());
     }

     private static String nativeTypeDescriptor(Class<?> type) {
         String name = type.getName();
         char c = name.charAt(0);
         if (c == '[') {
             return name;
         }
         if (type.isPrimitive()) {
             if (c == 'l') { // long
                 return "J";
             } else if (c == 'b' && name.length() == 7) { // boolean
                 return "Z";
             } else {
                 return String.valueOf(Character.toUpperCase(c));
             }
         }
         return "L" + name + ";";
     }

}

piotr