Use NIO's Files API to replace FileInputStream/FileOutputStream in some paths

common/src/main/java/org/apache/uniffle/common/util/RssUtils.java

@@ -22,7 +22,6 @@
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.File;
-import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.lang.reflect.Constructor;
@@ -33,6 +32,7 @@
 import java.nio.BufferUnderflowException;
 import java.nio.ByteBuffer;
 import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
 import java.util.Enumeration;
 import java.util.HashMap;
 import java.util.List;
@@ -86,7 +86,8 @@ public static Map<String, String> getPropertiesFromFile(String filename) {
     LOGGER.info("Load config from {}", filename);
     final Map<String, String> result = new HashMap<>();
 
-    try (InputStreamReader inReader = new InputStreamReader(new FileInputStream(file), StandardCharsets.UTF_8)) {
+    try (InputStreamReader inReader =
+             new InputStreamReader(Files.newInputStream(file.toPath()), StandardCharsets.UTF_8)) {
       Properties properties = new Properties();
       properties.load(inReader);
       properties.stringPropertyNames().forEach(k -> result.put(k, properties.getProperty(k).trim()));

server/src/main/java/org/apache/uniffle/server/LocalStorageChecker.java

@@ -18,9 +18,10 @@
 package org.apache.uniffle.server;
 
 import java.io.File;
-import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
 import java.util.List;
 
 import com.google.common.annotations.VisibleForTesting;
@@ -164,7 +165,7 @@ boolean checkStorageReadAndWrite() {
         }
         byte[] readData = new byte[1024];
         int readBytes = -1;
-        try (FileInputStream fis = new FileInputStream(writeFile)) {
+        try (InputStream fis = Files.newInputStream(writeFile.toPath())) {
           int hasReadBytes = 0;
           do {
             readBytes = fis.read(readData);

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

@@ -18,8 +18,8 @@
 package org.apache.uniffle.storage.handler.impl;
 
 import java.io.Closeable;
-import java.io.FileInputStream;
 import java.io.IOException;
+import java.io.InputStream;
 import java.nio.ByteBuffer;
 import java.util.List;
 
@@ -141,7 +141,7 @@ public synchronized void close() throws IOException {
     }
   }
 
-  public long copy(FileInputStream inputStream, int bufferSize) throws IOException {
+  public long copy(InputStream inputStream, int bufferSize) throws IOException {
     long start = fsDataOutputStream.getPos();
     IOUtils.copyBytes(inputStream, fsDataOutputStream, bufferSize);
     return fsDataOutputStream.getPos() - start;

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

@@ -20,19 +20,23 @@
 import java.io.Closeable;
 import java.io.DataOutputStream;
 import java.io.File;
-import java.io.FileOutputStream;
 import java.io.IOException;
+import java.io.OutputStream;
+import java.nio.file.Files;
 
 import org.apache.uniffle.storage.common.FileBasedShuffleSegment;
 
+import static java.nio.file.StandardOpenOption.APPEND;
+import static java.nio.file.StandardOpenOption.CREATE;
+
 public class LocalFileWriter implements Closeable {
 
   private DataOutputStream dataOutputStream;
-  private FileOutputStream fileOutputStream;
+  private OutputStream fileOutputStream;
   private long nextOffset;
 
   public LocalFileWriter(File file) throws IOException {
-    fileOutputStream = new FileOutputStream(file, true);
+    fileOutputStream = Files.newOutputStream(file.toPath(), CREATE, APPEND);
     // init fsDataOutputStream
     dataOutputStream = new DataOutputStream(fileOutputStream);
     nextOffset = file.length();

storage/src/main/java/org/apache/uniffle/storage/util/ShuffleStorageUtils.java

@@ -18,9 +18,10 @@
 package org.apache.uniffle.storage.util;
 
 import java.io.File;
-import java.io.FileInputStream;
 import java.io.IOException;
+import java.io.InputStream;
 import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
 import java.util.Collections;
 import java.util.List;
 
@@ -232,7 +233,7 @@ public static int getHeaderCrcLen() {
   }
 
   public static long uploadFile(File file, HdfsFileWriter writer, int bufferSize) throws IOException {
-    try (FileInputStream inputStream = new FileInputStream(file)) {
+    try (InputStream inputStream = Files.newInputStream(file.toPath())) {
       return writer.copy(inputStream, bufferSize);
     } catch (IOException e) {
       LOG.error("Fail to upload file {}, {}", file.getAbsolutePath(), e);