[New] Added new collection MapOfSets

li.strolch.utils/src/main/java/li/strolch/utils/collections/MapOfSets.java

@@ -0,0 +1,123 @@
+/*
+ * Copyright 2016 Robert von Burg <eitch@eitchnet.ch>
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package li.strolch.utils.collections;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
+
+/**
+ * @author Robert von Burg <eitch@eitchnet.ch>
+ */
+public class MapOfSets<T, U> {
+
+	private Map<T, Set<U>> mapOfSets;
+
+	public MapOfSets() {
+		this.mapOfSets = new HashMap<>();
+	}
+
+	public Set<T> keySet() {
+		return this.mapOfSets.keySet();
+	}
+
+	public Set<U> getSet(T t) {
+		return this.mapOfSets.get(t);
+	}
+
+	public boolean addElement(T t, U u) {
+		Set<U> set = this.mapOfSets.get(t);
+		if (set == null) {
+			set = new HashSet<>();
+			this.mapOfSets.put(t, set);
+		}
+		return set.add(u);
+	}
+
+	public boolean addSet(T t, Set<U> u) {
+		Set<U> set = this.mapOfSets.get(t);
+		if (set == null) {
+			set = new HashSet<>();
+			this.mapOfSets.put(t, set);
+		}
+		return set.addAll(u);
+	}
+
+	public boolean removeElement(T t, U u) {
+		Set<U> set = this.mapOfSets.get(t);
+		if (set == null) {
+			return false;
+		}
+		boolean removed = set.remove(u);
+		if (set.isEmpty()) {
+			this.mapOfSets.remove(t);
+		}
+
+		return removed;
+	}
+
+	public Set<U> removeSet(T t) {
+		return this.mapOfSets.remove(t);
+	}
+
+	public void clear() {
+		Set<Entry<T, Set<U>>> entrySet = this.mapOfSets.entrySet();
+		Iterator<Entry<T, Set<U>>> iter = entrySet.iterator();
+		while (iter.hasNext()) {
+			iter.next().getValue().clear();
+			iter.remove();
+		}
+	}
+
+	public boolean containsSet(T t) {
+		return this.mapOfSets.containsKey(t);
+	}
+
+	public boolean containsElement(T t, U u) {
+		Set<U> set = this.mapOfSets.get(t);
+		if (set == null)
+			return false;
+		return set.contains(u);
+	}
+
+	public int sizeKeys() {
+		return this.mapOfSets.size();
+	}
+
+	public int size() {
+		int size = 0;
+		Set<Entry<T, Set<U>>> entrySet = this.mapOfSets.entrySet();
+		Iterator<Entry<T, Set<U>>> iter = entrySet.iterator();
+		while (iter.hasNext()) {
+			size += iter.next().getValue().size();
+		}
+		return size;
+	}
+
+	public int size(T t) {
+		Set<U> set = this.mapOfSets.get(t);
+		if (set.size() == 0)
+			return 0;
+		return set.size();
+	}
+
+	public boolean isEmpty() {
+		return this.mapOfSets.isEmpty();
+	}
+}