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src/main/java/com/google/common/collect/Count.java

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+/*
+ * Copyright (C) 2011 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 java.io.Serializable;
+
+import javax.annotation.Nullable;
+
+import com.google.common.annotations.GwtCompatible;
+
+/**
+ * A mutable value of type {@code int}, for multisets to use in tracking counts
+ * of values.
+ *
+ * @author Louis Wasserman
+ */
+@GwtCompatible
+final class Count implements Serializable {
+	private int value;
+
+	Count(int value) {
+		this.value = value;
+	}
+
+	public int get() {
+		return value;
+	}
+
+	public int getAndAdd(int delta) {
+		int result = value;
+		value = result + delta;
+		return result;
+	}
+
+	public int addAndGet(int delta) {
+		return value += delta;
+	}
+
+	public void set(int newValue) {
+		value = newValue;
+	}
+
+	public int getAndSet(int newValue) {
+		int result = value;
+		value = newValue;
+		return result;
+	}
+
+	@Override
+	public int hashCode() {
+		return value;
+	}
+
+	@Override
+	public boolean equals(@Nullable Object obj) {
+		return obj instanceof Count && ((Count) obj).value == value;
+	}
+
+	@Override
+	public String toString() {
+		return Integer.toString(value);
+	}
+}