[DS-2058] More documentation, small cleanups.

dspace-api/src/main/java/org/dspace/content/DSpaceObject.java

@@ -53,10 +53,10 @@ public abstract class DSpaceObject implements Serializable, ReloadableEntity<jav
     private List<MetadataValue> metadata = new ArrayList<>();
 
     @OneToMany(fetch = FetchType.LAZY, mappedBy = "dso")
-    // Order by is here to ensure that the oldest handle is retrieved first,
+    // OrderBy is here to ensure that the oldest handle is retrieved first.
-    // multiple handles are assigned to the latest version of an item the original handle will have the lowest
+    // Multiple handles are assigned to the latest version of an item.
-    // identifier
+    // The original handle will have the lowest identifier.  This handle is the
-    // This handle is the preferred handle.
+    // preferred handle.
     @OrderBy("id ASC")
     private List<Handle> handles = new ArrayList<>();
 
@@ -122,6 +122,7 @@ public abstract class DSpaceObject implements Serializable, ReloadableEntity<jav
      *
      * @return internal ID of object
      */
+    @Override
     public UUID getID() {
         return id;
     }
@@ -142,6 +143,10 @@ public abstract class DSpaceObject implements Serializable, ReloadableEntity<jav
         this.handles = handle;
     }
 
+    /**
+     * Append to this object's list of Handles.
+     * @param handle the new Handle to be added.
+     */
     public void addHandle(Handle handle) {
         this.handles.add(handle);
     }

dspace-api/src/main/java/org/dspace/workflow/CurationTaskConfig.java

@@ -38,6 +38,7 @@ import org.xml.sax.SAXException;
  * @author mwood
  */
 public class CurationTaskConfig {
+    /** Name of the TaskSet that matches an unconfigured {@link TaskSet} name. */
     public static final String DEFAULT_TASKSET_NAME = "default";
 
     private final Map<String, TaskSet> collectionTasksetMap;

dspace-api/src/main/java/org/dspace/workflow/FlowStep.java

@@ -15,8 +15,13 @@ import javax.validation.constraints.NotNull;
  * Linkage between a workflow step and some {@link org.dspace.curate.CurationTask}s.
  */
 public class FlowStep {
+    /** Name of this workflow step. */
     public final String step;
+
+    /** Queue on which to run curation tasks, or {@code null} for immediate run. */
     public final String queue;
+
+    /** Curation tasks to be run in this workflow step. */
     public final List<Task> tasks = new ArrayList<>();
 
     /**

dspace-api/src/main/java/org/dspace/workflow/Task.java

@@ -26,8 +26,13 @@ import javax.validation.constraints.NotNull;
  * (email addresses) to be notified when the curation task returns a given status.
  */
 public class Task {
+    /** Name of the curation task. */
     public final String name;
+
+    /** Effects of curation task completion on the workflow step. */
     public final List<String> powers = new ArrayList<>();
+
+    /** Contacts to be notified on a given completion status. */
     public final Map<String, List<String>> contacts = new HashMap<>();
 
     /**

dspace-api/src/main/java/org/dspace/workflow/TaskSet.java

@@ -15,7 +15,10 @@ import javax.validation.constraints.NotNull;
  * attached to a workflow.
  */
 public class TaskSet {
+    /** Name of this TaskSet. */
     public final String name;
+
+    /** The {@link FlowStep}s assigned to this TaskSet. */
     public final List<FlowStep> steps;
 
     /**