Java 使用 NIO 进行文件合并输出详解编程语言

  
import java.io.*; 
import java.nio.*; 
import java.nio.channels.*; 
 
public class NIOCat { 
 
  public static void main(String[] args) throws IOException { 
 
    if (args.length < 2) { 
      System.err.println("Usage: java NIOCat inFile1 inFile2... outFile"); 
      return; 
    } 
     
    ByteBuffer[] buffers = new ByteBuffer[args.length-1]; 
    for (int i = 0; i < args.length-1; i++) { 
      RandomAccessFile raf = new RandomAccessFile(args[i], "r"); 
      FileChannel channel = raf.getChannel(); 
      buffers[i] = channel.map(FileChannel.MapMode.READ_ONLY, 0, raf.length()); 
    } 
     
    FileOutputStream outFile = new FileOutputStream(args[args.length-1]); 
    FileChannel out = outFile.getChannel(); 
    out.write(buffers); 
    out.close();      
  } 
}