注意：先开的流要最后关

用字节流传输

public class Demo {	public static void main(String[] args){		FileInputStream fis = null;		FileOutputStream fos = null;		try {			fis = new FileInputStream("d:\\aaa.txt");			fos = new FileOutputStream("d:\\bbb.txt");						//字节输入流  读取一个字节   写一个字节			int len =0;			while((len=fis.read())!=-1) {				fos.write(len);			}		} catch (Exception e) {			// TODO Auto-generated catch block			e.printStackTrace();		}finally {			if(fos!=null) {				try {					fos.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}			}			if(fis!=null) {				try {					fis.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}			}		}	}}

 用字符数组传输

public class Demo {	public static void main(String[] args){		FileInputStream fis = null;		FileOutputStream fos = null;		try {			fis = new FileInputStream("d:\\aaa.txt");			fos = new FileOutputStream("d:\\bbb.txt");						//定义字符数组			byte[] b = new byte[1024];			//读取操作			int len = 0;			while((len = fis.read(b))!=-1) {				fos.write(b,0,len);			}		} catch (Exception e) {			// TODO Auto-generated catch block			e.printStackTrace();		}finally {			if(fos!=null) {				try {					fos.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}			}			if(fis!=null) {				try {					fis.close();				} catch (IOException e) {					// TODO Auto-generated catch block					e.printStackTrace();				}			}		}	}}