瞭解了InputStream和OutputStream後, 簡單的文件copy程序就很簡單了。 java
import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.InputStream; import java.io.OutputStream; public class CopyFile { /** * @param args */ public static void main(String[] args) throws Exception { // TODO Auto-generated method stub InputStream in = new FileInputStream("helloWorld.txt"); byte[] bs= new byte[1024]; int b = -1; int start = 0; while(( b = in.read()) != -1){ bs[start] = (byte)b; start++; } System.out.println(new String(bs, 0, start)); in.close(); OutputStream out = new FileOutputStream("copyhelloworld.txt"); out.write(bs, 0, start); out.close(); } }