Help wanted with Java generics

from_AppleImage.java

/**
 * AppleImage is an abstract class that represents a generic interface
 * for handing graphic images.  This abstraction is needed because not
 * all graphic routines use BufferedImage.  AppleImage itself acts as
 * a factory for creating "the best" AppleImage subclass.
 * <p>
 * Date Created: Mar 25, 2003
 * @author Rob Greene
 */
public abstract class AppleImage {
	/**
	 * The specific file extension to use.
	 */
	private String fileExtension;
	/**
	 * All available image formats.  This is instance specific since
	 * (in theory) there could be different AppleImages being used.
	 */
	private String[] availableExtensions;
	/**
	 * Create a specific instance of AppleImage.  This has been coded
	 * using Reflection to ease native compilation for the most part.
	 */
	public static AppleImage create(int width, int height) {
		String[] classes = {
			"ImageIoImage", "SunJpegImage", "SwtImage" }; //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
		Class[] constructorArgClasses = new Class[] {
			int.class, int.class };
		Object[] constructorArgs = new Object[] {
			new Integer(width), new Integer(height) };
		for (int i=0; i<classes.length; i++) {
			try {
				Class appleImageClass = Class.forName(
					"com.webcodepro.applecommander.storage.filters.imagehandlers."  //$NON-NLS-1$
					+ classes[i]);
				Constructor constructor = 
					appleImageClass.getConstructor(constructorArgClasses);
				AppleImage appleImage = (AppleImage) 
					constructor.newInstance(constructorArgs);
				return appleImage;
			} catch (Exception ignored) {
				// There are multiple exceptions that can be thrown here.
				// For the most part, this is expected and simply means that
				// the image handler is not available on the platform.
			}
		}
		return null;
	}

Okay, the issue here is that this code is considered "unsafe" and if you specify -Xlint:unchecked it'll tell you what's wrong with it:

executableCmdJar:
    [javac] Compiling 1 source file to /srv/tjcarter/Source/iKarith/AppleCommander/work/classes
    [javac] /srv/tjcarter/Source/iKarith/AppleCommander/src/com/webcodepro/applecommander/storage/filters/imagehandlers/AppleImage.java:62: warning: [unchecked] unchecked call to getConstructor(Class<?>...) as a member of the raw type Class
    [javac]                                     appleImageClass.getConstructor(constructorArgClasses);
    [javac]                                                                   ^
    [javac]   where T is a type-variable:
    [javac]     T extends Object declared in class Class
    [javac] 1 warning
      [jar] Building jar: /srv/tjcarter/Source/iKarith/AppleCommander/work/dist/AppleCommander-1.3.5.14-ac.jar

BUILD SUCCESSFUL
Total time: 1 second

I've figured out how best to fix several of these, but not this one. Can anyone suggest how it ought to be fixed?

Apparently the solution looks something like this:

diff --git a/src/com/webcodepro/applecommander/storage/filters/imagehandlers/AppleImage.java b/src/com/webcodepro/applecommander/storage/filters/imagehandlers/AppleImage.java
index 5376ef1..540c15b 100644
--- a/src/com/webcodepro/applecommander/storage/filters/imagehandlers/AppleImage.java
+++ b/src/com/webcodepro/applecommander/storage/filters/imagehandlers/AppleImage.java
@@ -49,17 +49,17 @@ public abstract class AppleImage {
 	public static AppleImage create(int width, int height) {
 		String[] classes = {
 			"ImageIoImage", "SunJpegImage", "SwtImage" }; //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
-		Class[] constructorArgClasses = new Class[] {
-			int.class, int.class };
+		Class<?> constructorArgType = AppleImage.class;
+		Class<?>[] constructorArgClasses = new Class[] { AppleImage.class };
 		Object[] constructorArgs = new Object[] {
 			new Integer(width), new Integer(height) };
 		for (int i=0; i<classes.length; i++) {
 			try {
-				Class appleImageClass = Class.forName(
+				Class<?> appleImageClass = Class.forName(
 					"com.webcodepro.applecommander.storage.filters.imagehandlers."  //$NON-NLS-1$
 					+ classes[i]);
-				Constructor constructor = 
-					appleImageClass.getConstructor(constructorArgClasses);
+				Constructor constructor =
+					constructorArgType.getConstructor(constructorArgClasses);
 				AppleImage appleImage = (AppleImage) 
 					constructor.newInstance(constructorArgs);
 				return appleImage;

I can't say I fully understand that.