Update #0 - First Release

sources/main/java/com/google/common/collect/SingletonImmutableTable.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2009 The Guava Authors
+ *
+ * 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 com.google.common.collect;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+import java.util.Map;
+
+import com.google.common.annotations.GwtCompatible;
+
+/**
+ * An implementation of {@link ImmutableTable} that holds a single cell.
+ *
+ * @author Gregory Kick
+ */
+@GwtCompatible
+class SingletonImmutableTable<R, C, V> extends ImmutableTable<R, C, V> {
+	final R singleRowKey;
+	final C singleColumnKey;
+	final V singleValue;
+
+	SingletonImmutableTable(R rowKey, C columnKey, V value) {
+		this.singleRowKey = checkNotNull(rowKey);
+		this.singleColumnKey = checkNotNull(columnKey);
+		this.singleValue = checkNotNull(value);
+	}
+
+	SingletonImmutableTable(Cell<R, C, V> cell) {
+		this(cell.getRowKey(), cell.getColumnKey(), cell.getValue());
+	}
+
+	@Override
+	public ImmutableMap<R, V> column(C columnKey) {
+		checkNotNull(columnKey);
+		return containsColumn(columnKey) ? ImmutableMap.of(singleRowKey, singleValue) : ImmutableMap.<R, V>of();
+	}
+
+	@Override
+	public ImmutableMap<C, Map<R, V>> columnMap() {
+		return ImmutableMap.of(singleColumnKey, (Map<R, V>) ImmutableMap.of(singleRowKey, singleValue));
+	}
+
+	@Override
+	public ImmutableMap<R, Map<C, V>> rowMap() {
+		return ImmutableMap.of(singleRowKey, (Map<C, V>) ImmutableMap.of(singleColumnKey, singleValue));
+	}
+
+	@Override
+	public int size() {
+		return 1;
+	}
+
+	@Override
+	ImmutableSet<Cell<R, C, V>> createCellSet() {
+		return ImmutableSet.of(cellOf(singleRowKey, singleColumnKey, singleValue));
+	}
+
+	@Override
+	ImmutableCollection<V> createValues() {
+		return ImmutableSet.of(singleValue);
+	}
+}