Cleaned up some PMD and compile warnings.

core/src/main/java/gov/nist/secauto/metaschema/core/metapath/function/FunctionLibrary.java

@@ -58,7 +58,7 @@ public void registerFunction(@NonNull IFunction function) {
     registerFunctionByName(function);
   }
 
-  protected void registerFunctionByQName(@NonNull IFunction function) {
+  private void registerFunctionByQName(@NonNull IFunction function) {
     QName qname = function.getQName();
     IFunction duplicate;
     synchronized (this) {
@@ -75,7 +75,7 @@ protected void registerFunctionByQName(@NonNull IFunction function) {
     }
   }
 
-  protected void registerFunctionByName(@NonNull IFunction function) {
+  private void registerFunctionByName(@NonNull IFunction function) {
     String name = function.getName();
     synchronized (this) {
       NamedFunctionSet functions = libraryByName.get(name);

core/src/main/java/gov/nist/secauto/metaschema/core/metapath/item/node/AbstractInstanceNodeItem.java

@@ -32,7 +32,7 @@
 
 import edu.umd.cs.findbugs.annotations.NonNull;
 
-public abstract class AbstractInstanceNodeItem<
+abstract class AbstractInstanceNodeItem<
     D extends IDefinition,
     I extends INamedInstance,
     P extends IModelNodeItem<? extends IModelDefinition, ? extends INamedInstance>>

core/src/main/java/gov/nist/secauto/metaschema/core/model/AbstractModuleLoader.java

@@ -52,7 +52,6 @@
  * @param <M>
  *          the Java type of the Metaschema module loaded by this loader
  */
-// REFACTOR: make an IModuleLoader interface
 public abstract class AbstractModuleLoader<T, M extends IModuleExtended<M, ?, ?, ?, ?>>
     extends AbstractLoader<M>
     implements IModuleLoader<M> {
@@ -119,7 +118,8 @@ protected M parseResource(@NonNull URI resource, @NonNull Deque<URI> visitedReso
 
     // now check if this Metaschema imports other metaschema
     List<URI> imports = getImports(binding);
-    @NonNull Map<URI, M> importedModules;
+    @NonNull
+    Map<URI, M> importedModules;
     if (imports.isEmpty()) {
       importedModules = ObjectUtils.notNull(Collections.emptyMap());
     } else {

core/src/main/java/gov/nist/secauto/metaschema/core/model/IAttributable.java

@@ -40,7 +40,7 @@
  */
 public interface IAttributable {
   @NonNull
-  String DEFAULT_PROPERY_NAMESPACE = MetaschemaModelConstants.XML_NAMESPACE;
+  String DEFAULT_PROPERY_NAMESPACE = IModule.XML_NAMESPACE;
 
   @NonNull
   Map<Key, Set<String>> EMPTY = CollectionUtil.emptyMap();

core/src/main/java/gov/nist/secauto/metaschema/core/model/IChoiceGroupInstance.java

@@ -28,11 +28,27 @@
 
 import gov.nist.secauto.metaschema.core.datatype.markup.MarkupMultiline;
 
+import java.util.Locale;
+
 import edu.umd.cs.findbugs.annotations.NonNull;
 
 public interface IChoiceGroupInstance
     extends IModelInstanceAbsolute, IContainerModelGrouped {
 
+  int DEFAULT_CHOICE_GROUP_GROUP_AS_MAX_OCCURS = -1;
+  @NonNull
+  String DEFAULT_JSON_DISCRIMINATOR_PROPERTY_NAME = "object-type";
+
+  /**
+   * {@inheritDoc}
+   *
+   * @see #DEFAULT_CHOICE_GROUP_GROUP_AS_MAX_OCCURS
+   */
+  @Override
+  default int getMaxOccurs() {
+    return DEFAULT_CHOICE_GROUP_GROUP_AS_MAX_OCCURS;
+  }
+
   /**
    * Retrieve the Metaschema assembly definition on which this instance is
    * declared.
@@ -58,6 +74,7 @@ default ModelType getModelType() {
    * Get the JSON property to use to discriminate between JSON objects.
    *
    * @return the discriminator property
+   * @see #DEFAULT_JSON_DISCRIMINATOR_PROPERTY_NAME
    */
   @NonNull
   String getJsonDiscriminatorProperty();
@@ -72,4 +89,15 @@ default MarkupMultiline getRemarks() {
     // no remarks
     return null;
   }
+
+  @SuppressWarnings("null")
+  @Override
+  default String toCoordinates() {
+    return String.format("%s:%s-instance:%s/%s@%d",
+        getContainingDefinition().getContainingModule().getShortName(),
+        getModelType().toString().toLowerCase(Locale.ROOT),
+        getContainingDefinition().getName(),
+        getGroupAsName(),
+        hashCode());
+  }
 }

core/src/main/java/gov/nist/secauto/metaschema/core/model/IChoiceInstance.java

@@ -26,6 +26,8 @@
 
 package gov.nist.secauto.metaschema.core.model;
 
+import java.util.Locale;
+
 /**
  * A marker interface for a choice of allowed instances in a Metachema.
  */
@@ -71,4 +73,14 @@ default int getMaxOccurs() {
   default boolean isEffectiveValueWrappedInXml() {
     throw new UnsupportedOperationException("not applicable");
   }
+
+  @SuppressWarnings("null")
+  @Override
+  default String toCoordinates() {
+    return String.format("%s:%s-instance:%s@%d",
+        getContainingDefinition().getContainingModule().getShortName(),
+        getModelType().toString().toLowerCase(Locale.ROOT),
+        getContainingDefinition().getName(),
+        hashCode());
+  }
 }

core/src/main/java/gov/nist/secauto/metaschema/core/model/IContainerModel.java

@@ -47,7 +47,6 @@ default boolean hasChildren() {
    *
    * @return the containing Metaschema module definition
    */
-  // REFACTOR: can this be removed?
   @NonNull
   IAssemblyDefinition getOwningDefinition();
 

core/src/main/java/gov/nist/secauto/metaschema/core/model/IDefinition.java

@@ -28,6 +28,8 @@
 
 import gov.nist.secauto.metaschema.core.model.constraint.impl.IFeatureValueConstrained;
 
+import java.util.Locale;
+
 import edu.umd.cs.findbugs.annotations.NonNull;
 
 public interface IDefinition extends IModelElement, INamed, IAttributable, IFeatureValueConstrained {
@@ -81,9 +83,11 @@ default boolean isInline() {
   @SuppressWarnings("null")
   @Override
   default String toCoordinates() {
-    return String.format("%s:%s:%s(%d)",
+    return String.format("%s:%s-definition:%s(%d)",
         getContainingModule().getShortName(),
-        getModelType(),
-        getName(), hashCode());
+        getModelType().toString().toUpperCase(Locale.ROOT),
+        getName(),
+        hashCode());
   }
+
 }

core/src/main/java/gov/nist/secauto/metaschema/core/model/IFeatureInlinedDefinition.java → core/src/main/java/gov/nist/secauto/metaschema/core/model/IFeatureDefinitionInstanceInlined.java

@@ -28,6 +28,8 @@
 
 import gov.nist.secauto.metaschema.core.datatype.markup.MarkupLine;
 
+import java.util.Locale;
+
 import edu.umd.cs.findbugs.annotations.NonNull;
 import edu.umd.cs.findbugs.annotations.Nullable;
 
@@ -40,8 +42,7 @@
  * @param <INSTANCE>
  *          the associated instance Java type
  */
-// REFACTOR: rename to IFeatureInlinedDefinitionInstance
-public interface IFeatureInlinedDefinition<DEFINITION extends IDefinition, INSTANCE extends INamedInstance>
+public interface IFeatureDefinitionInstanceInlined<DEFINITION extends IDefinition, INSTANCE extends INamedInstance>
     extends IDefinition, INamedInstance {
   @Override
   default boolean isInline() {
@@ -86,24 +87,26 @@ default Object getEffectiveDefaultValue() {
   }
 
   /**
-   * Generates a "coordinate" string for the provided information element
-   * instance.
+   * Generates a "coordinate" string for the provided inline definition instance.
    *
    * A coordinate consists of the element's:
    * <ul>
    * <li>containing Metaschema module's short name</li>
    * <li>model type</li>
-   * <li>name</li>
+   * <li>definition name</li>
+   * <li>hash code</li>
    * </ul>
    *
    * @return the coordinate
    */
+  @SuppressWarnings("null")
   @Override
   default String toCoordinates() {
     IModule module = getContainingModule();
-    return String.format("%s:%s:%s",
+    return String.format("%s:%s-inline-definition:%s@%d",
         module.getShortName(),
-        getModelType(),
-        getEffectiveName());
+        getModelType().toString().toLowerCase(Locale.ROOT),
+        getContainingDefinition().getName(),
+        hashCode());
   }
 }

core/src/main/java/gov/nist/secauto/metaschema/core/model/IFeatureDefinitionReferenceInstance.java

@@ -28,6 +28,8 @@
 
 import gov.nist.secauto.metaschema.core.datatype.markup.MarkupLine;
 
+import java.util.Locale;
+
 import edu.umd.cs.findbugs.annotations.NonNull;
 import edu.umd.cs.findbugs.annotations.Nullable;
 
@@ -39,6 +41,11 @@ public interface IFeatureDefinitionReferenceInstance<
   @Override
   DEFINITION getDefinition();
 
+  /**
+   * Get the instance this definition is combined with.
+   *
+   * @return the instance or {@code null} if the definition is not inline
+   */
   @Nullable
   default INSTANCE getInlineInstance() {
     return null;
@@ -107,7 +114,7 @@ default Object getEffectiveDefaultValue() {
    * <li>model type</li>
    * <li>name</li>
    * <li>hash code</li>
-   * <li>the hash code of the definition</li>
+   * <li>the hash code of the referenced definition</li>
    * </ul>
    *
    * @return the coordinate
@@ -116,11 +123,11 @@ default Object getEffectiveDefaultValue() {
   @Override
   default String toCoordinates() {
     IDefinition definition = getDefinition();
-    return String.format("%s:%s:%s@%d(%d)",
+    return String.format("%s:%s-instance:%s@%d(%d)",
         getContainingDefinition().getContainingModule().getShortName(),
-        getModelType(),
+        getModelType().toString().toLowerCase(Locale.ROOT),
         definition.getName(),
         hashCode(),
-        definition.isInline() ? 0 : definition.hashCode());
+        definition.hashCode());
   }
 }

core/src/main/java/gov/nist/secauto/metaschema/core/model/IFieldInstance.java

@@ -29,6 +29,8 @@
 import javax.xml.namespace.QName;
 
 public interface IFieldInstance extends IField, INamedModelInstance, IValuedInstance {
+  boolean DEFAULT_FIELD_IN_XML_WRAPPED = true;
+
   @Override
   default String getXmlNamespace() {
     return INamedModelInstance.super.getXmlNamespace();
@@ -47,6 +49,9 @@ default QName getXmlQName() {
    *
    * @return {@code true} if an XML wrapper is required, or {@code false}
    *         otherwise
+   * @see #DEFAULT_FIELD_IN_XML_WRAPPED
    */
-  boolean isInXmlWrapped();
+  default boolean isInXmlWrapped() {
+    return DEFAULT_FIELD_IN_XML_WRAPPED;
+  }
 }

core/src/main/java/gov/nist/secauto/metaschema/core/model/IFieldInstanceGrouped.java

@@ -26,7 +26,6 @@
 
 package gov.nist.secauto.metaschema.core.model;
 
-// REFACTOR: check that instances cannot have a data type that allows unwrapped
 public interface IFieldInstanceGrouped extends INamedModelInstanceGrouped, IFieldInstance {
 
   /**

core/src/main/java/gov/nist/secauto/metaschema/core/model/IFlagInstance.java

@@ -34,6 +34,8 @@
 
 public interface IFlagInstance extends IFlag, IValuedInstance, IInstanceAbsolute {
 
+  boolean DEFAULT_FLAG_REQUIRED = false;
+
   @Override
   IContainerFlag getParentContainer();
 
@@ -57,6 +59,9 @@ default QName getXmlQName() {
    * Determines if a flag value is required to be provided.
    *
    * @return {@code true} if a value is required, or {@code false} otherwise
+   * @see #DEFAULT_FLAG_REQUIRED
    */
-  boolean isRequired();
+  default boolean isRequired() {
+    return DEFAULT_FLAG_REQUIRED;
+  }
 }

core/src/main/java/gov/nist/secauto/metaschema/core/model/IGroupable.java

@@ -38,12 +38,20 @@
 
 public interface IGroupable extends IInstanceAbsolute, IKeyed {
 
+  int DEFAULT_GROUP_AS_MIN_OCCURS = 0;
+  int DEFAULT_GROUP_AS_MAX_OCCURS = 1;
+  @NonNull
+  JsonGroupAsBehavior DEFAULT_JSON_GROUP_AS_BEHAVIOR = JsonGroupAsBehavior.SINGLETON_OR_LIST;
+  @NonNull
+  XmlGroupAsBehavior DEFAULT_XML_GROUP_AS_BEHAVIOR = XmlGroupAsBehavior.UNGROUPED;
+
   /**
    * Get the minimum cardinality for this associated instance. This value must be
    * less than or equal to the maximum cardinality returned by
    * {@link #getMaxOccurs()}.
    *
    * @return {@code 0} or a positive integer value
+   * @see #DEFAULT_GROUP_AS_MIN_OCCURS
    */
   int getMinOccurs();
 
@@ -53,6 +61,7 @@ public interface IGroupable extends IInstanceAbsolute, IKeyed {
    * {@link #getMinOccurs()}, or {@code -1} if unbounded.
    *
    * @return a positive integer value or {@code -1} if unbounded
+   * @see #DEFAULT_GROUP_AS_MAX_OCCURS
    */
   int getMaxOccurs();
 
@@ -118,9 +127,15 @@ default QName getEffectiveXmlGroupAsQName() {
   /**
    * Gets the configured JSON group-as strategy. A JSON group-as strategy is only
    * required when {@link #getMaxOccurs()} > 1.
+   * <p>
+   * The default for this method is {@link JsonGroupAsBehavior#NONE}, since the
+   * default behavior is to have no grouping. If {@link #getMaxOccurs()} is
+   * greater than {@code 1}, then the default behavior is
+   * {@code #DEFAULT_JSON_GROUP_AS_BEHAVIOR}.
    *
    * @return the JSON group-as strategy, or {@code JsonGroupAsBehavior#NONE} if
    *         {@link #getMaxOccurs()} = 1
+   * @see #DEFAULT_JSON_GROUP_AS_BEHAVIOR
    */
   @NonNull
   default JsonGroupAsBehavior getJsonGroupAsBehavior() {
@@ -133,10 +148,11 @@ default JsonGroupAsBehavior getJsonGroupAsBehavior() {
    *
    * @return the JSON group-as strategy, or {@code XmlGroupAsBehavior#UNGROUPED}
    *         if {@link #getMaxOccurs()} = 1
+   * @see #DEFAULT_XML_GROUP_AS_BEHAVIOR
    */
   @NonNull
   default XmlGroupAsBehavior getXmlGroupAsBehavior() {
-    return XmlGroupAsBehavior.UNGROUPED;
+    return DEFAULT_XML_GROUP_AS_BEHAVIOR;
   }
 
   /**

core/src/main/java/gov/nist/secauto/metaschema/core/model/IInstance.java

@@ -72,12 +72,5 @@ default IModule getContainingModule() {
    */
   @SuppressWarnings("null")
   @Override
-  default String toCoordinates() {
-    IModule module = getContainingModule();
-
-    // TODO: revisit this to add more context i.e. the containing definition
-    return String.format("%s:%s",
-        module.getShortName(),
-        getModelType());
-  }
+  String toCoordinates();
 }

core/src/main/java/gov/nist/secauto/metaschema/core/model/IModelElement.java

@@ -52,7 +52,6 @@ public interface IModelElement extends IDefaultable {
    *
    * @return the coordinates
    */
-  // REFACTOR: reduce implementations
   @NonNull
   String toCoordinates();
 

core/src/main/java/gov/nist/secauto/metaschema/core/model/IModule.java

@@ -40,6 +40,8 @@
 
 public interface IModule {
 
+  String XML_NAMESPACE = "http://csrc.nist.gov/ns/oscal/metaschema/1.0";
+
   /**
    * Retrieves the location where the Metaschema module was loaded from.
    *