Address review comments

Addressed various review comments:

1) Added comments describing accessedContainer and valueClassUsedInCode
fields of ClassConfiguration;
2) Replaced line comments with block comments;
3) Replaced a call to ClassWriter.visitNestHost with a call to
ClassWriter.visitNestMember.

Signed-off-by:  Henry Zongaro <zongaro@ca.ibm.com>

test/functional/Valhalla/src/org/openj9/test/lworld/ValueTypeGenerator.java

@@ -53,7 +53,15 @@ private static class ClassConfiguration {
 		private String nestHost;
 		private boolean isVerifiable;
 		private boolean isReference;
+
+		/**
+		 * @see setAccessedContainer
+		 */
 		private ClassConfiguration accessedContainer;
+
+		/**
+		 * @see setValueClassUsedInCode
+		 */
 		private ClassConfiguration valueClassUsedInCode;
 
 		public ClassConfiguration(String name) {
@@ -97,18 +105,51 @@ public boolean isVerifiable() {
 			return this.isVerifiable;
 		}
 
+		/**
+		 * This method specifies a reference class - whose fields are expected to be of
+		 * value types - an instance of which will be an argument to the
+		 * {@code testUnresolvedValueTypePutField} and {@code testUnresolvedValueTypeGetField}
+		 * methods that will be generated for the current class.  Those methods will perform
+		 * {@code PUTFIELD} or {@code GETFIELD} operations, respectively, on the fields of
+		 * the {@code accessedContainer} instance.
+		 *
+		 * The intention is to test delaying resolution of the fields and their types,
+		 * particularly its effect on code generated by the JIT compiler.
+		 */
 		public void setAccessedContainer(ClassConfiguration accessedContainer) {
 			this.accessedContainer = accessedContainer;
 		}
 
+		/**
+		 * @see setAccessedContainer
+		 */
 		public ClassConfiguration getAccessedContainer() {
 			return accessedContainer;
 		}
 
+		/**
+		 * This method specifies a value type class that will be used in code generated
+		 * for the {@code testUnresolvedValueTypeDefaultValue} and
+		 * {@code testUnresolvedValueTypeWithField} methods of the current class.
+		 * The former will conditionally perform a {@code DEFAULTVALUE} operation on the
+		 * value type and the latter will conditionally perform a series of
+		 * {@code WITHFIELD} operations on the fields of an instance of the value type.
+		 * The instance should be passed to {@code testUnresolvedValueTypeWithField} via an
+		 * argument of type {@link java.lang.Object}.
+		 *
+		 * The value type class will be declared to be a {@code NestMember} of the current
+		 * class, and must in turn declare the current class to be its {@code NestHost}.
+		 *
+		 * The intention is to test delayed resolution of the value type class, particularly
+		 * its effect on code generated by the JIT compiler.
+		 */
 		public void setValueClassUsedInCode(ClassConfiguration valueClassUsedInCode) {
 			this.valueClassUsedInCode = valueClassUsedInCode;
 		}
 
+		/**
+		 * @see setValueClassUsedInCode
+		 */
 		public ClassConfiguration getValueClassUsedInCode() {
 			return valueClassUsedInCode;
 		}
@@ -149,7 +190,7 @@ private static byte[] generateClass(ClassConfiguration config) {
 		}
 
 		if (valueUsedInCode != null) {
-			cw.visitNestHost(valueUsedInCode);
+			cw.visitNestMember(valueUsedInCode);
 		}
 
 		int makeMaxLocal = 0;
@@ -1117,15 +1158,15 @@ public static void generateClassFile(String name, byte[] bytes) {
 	}
 
 	public static Class<?> generateValueClass(String name, String[] fields) throws Throwable {
-		ClassConfiguration classConfig = new ClassConfiguration(name, fields);
-
-		byte[] bytes = generateClass(classConfig);
-		return generator.defineClass(name, bytes, 0, bytes.length);
+		return generateValueClass(name, fields, null);
 	}
 
 	public static Class<?> generateValueClass(String name, String[] fields, String nestHost) throws Throwable {
 		ClassConfiguration classConfig = new ClassConfiguration(name, fields);
-		classConfig.setNestHost(nestHost);
+
+		if (nestHost != null) {
+			classConfig.setNestHost(nestHost);
+		}
 
 		byte[] bytes = generateClass(classConfig);
 		return generator.defineClass(name, bytes, 0, bytes.length);