在Java 9中何时使用InputStream的readNBytes()方法？

Since Java 9, the readNBytes() method can be added to the InputStream class. This method reads the requested number of bytes from an input stream into the given byte array. This method blocks until len bytes of input data have read, end of a stream is detected, or an exception is thrown. The readNBytes() method doesn't close an input stream. This method can be useful to avoid memory problems with large files.

public int readNBytes(byte[] b, int off, int len) throws IOException

在下面的示例中，我们在源文件夹中创建了一个名为“Technology.txt”的文件，其中包含简单的数据：{ "JAVA", "PYTHON", "JAVASCRIPT", "SELENIUM", "SCALA"}。

示例

import java.io.*;
import java.util.stream.*;
import java.nio.*;
import java.nio.file.*;

public class InputStreamReadNByteMethodTest {
   InputStream inputStream = nputStreamReadNByteMethodTest.class.getResourceAsStream("Technology.txt");

   public void testReadNBytes() throws Exception {
      final byte[] data = new byte[10];
      inputStream.readNBytes(data, 0, 7);
      System.out.println(new String(data));
   }
   public static void main(String args[]) throws Exception {
      InputStreamReadNByteMethodTest t = new InputStreamReadNByteMethodTest();
      t.testReadNBytes();  
   }
}

输出

"JAVA",

以上就是在Java 9中何时使用InputStream的readNBytes()方法？的详细内容，更多请关注php中文网其它相关文章！