[MINOR] feat(server): Introduce LocalFileNullDeviceWriter to flush da…

…ta into null device (#2337)

### What changes were proposed in this pull request?

Introduce a new implementation of FileWriter, named LocalFileNullDeviceWriter.

### Why are the changes needed?

Write all the data into null device, specify LocalFileNullDeviceWriter for test the ceiling performance of flush event but kept the cost for file level api.

### Does this PR introduce _any_ user-facing change?

No.

### How was this patch tested?

Tested on our test cluster.

storage/src/main/java/org/apache/uniffle/storage/handler/impl/LocalFileNullDeviceWriter.java

@@ -0,0 +1,37 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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 org.apache.uniffle.storage.handler.impl;
+
+import java.io.File;
+import java.io.IOException;
+
+import com.google.common.annotations.VisibleForTesting;
+
+/** A shuffle writer that write data into null device for performance test purpose only. */
+public class LocalFileNullDeviceWriter extends LocalFileNioWriter {
+  private static final File NULL_DEVICE_FILE = new File("/dev/null");
+
+  @VisibleForTesting
+  public LocalFileNullDeviceWriter(File file) throws IOException {
+    this(file, 8 * 1024);
+  }
+
+  public LocalFileNullDeviceWriter(File file, int bufferSize) throws IOException {
+    super(NULL_DEVICE_FILE, bufferSize);
+  }
+}