Merge branch 'master' of github.com:bculkin2442/bjc-utils2

1 files changed, 23 insertions, 1 deletions

diff --git a/base/src/main/java/bjc/utils/funcutils/SetUtils.java b/base/src/main/java/bjc/utils/funcutils/SetUtils.java
index eac417c..d57ac00 100644
--- a/base/src/main/java/bjc/utils/funcutils/SetUtils.java
+++ b/base/src/main/java/bjc/utils/funcutils/SetUtils.java
@@ -5,10 +5,21 @@ import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
 
+/**
+ * Various utility functions dealing with sets.
+ * @author bjculkin
+ *
+ */
 public class SetUtils {
+	/**
+	 * Create a power-set (set of all subsets) of a given set.
+	 * @param originalSet The set to create a power-set of.
+	 * @return The power-set of the set.
+	 */
 	public static <T> Set<Set<T>> powerSet(Set<T> originalSet) {
 		Set<Set<T>> sets = new HashSet<Set<T>>();
 
+		// Special-case empty input
 		if (originalSet.isEmpty()) {
 			sets.add(new HashSet<T>());
 			return sets;
@@ -16,13 +27,18 @@ public class SetUtils {
 
 		List<T> list = new ArrayList<T>(originalSet);
 
+		// Add original set to list.
 		T head = list.get(0);
 
+		// Trim leading element from set.
 		Set<T> rest = new HashSet<T>(list.subList(1, list.size()));
 
-		for (Set<T> set : powerSet(rest)) {
+		Set<Set<T>> remSets = powerSet(rest);
+		
+		for (Set<T> set : remSets) {
 			Set<T> newSet = new HashSet<T>();
 
+			// Create a new set with the removed element.
 			newSet.add(head);
 			newSet.addAll(set);
 
@@ -33,6 +49,12 @@ public class SetUtils {
 		return sets;
 	}
 
+	/**
+	 * Utility method for set construction.
+	 * @param elms The elements to stick in the set.
+	 * @return A set containing the specified elements.
+	 */
+	@SafeVarargs
 	public static <T> Set<T> toSet(T... elms) {
 		Set<T> set = new HashSet<>();