File I/O的总结 - 爱码网

1读写字符文件
　　BufferedReader br=new BufferedReader(new FileReader("文件路径"));
　　BufferedWriter bw=new BufferedWriter(new FileWriter("文件路径"，boolean));

public static void main (String[] args) throws Exception{

BufferedWriter bw=new BufferedWriter(new FileWriter("src/a.txt");

BufferedReader br=new BufferedReader(new FileReader("src/d.txt"));

String str=null;

while((str=br.readLine())!=-1){

System.out.println(str);

}

bw.close();

br.close();

}

2读写字节文件
　　DataInputStream dis=new DataInputStream(new FileInputStream("文件路径"));
　　DataOutputStream dos=new DataOutputStream(new FileOutputStream("文件路径"));

public static void main(String[] args) throws Exception {
DataInputStream dis=new DataInputStream(new FileInputStream("src/a.jpg"));
int a=dis.read();
System.out.println(a);
dis.close();

DataOutputStream dos=new DataOutputStream(new FileOutputStream("src/b.jpg"));
dos.write(255);
dos.close();

//复制a.jpg--->b.jpg
DataInputStream dis1=new DataInputStream(new FileInputStream("src/a.jpg"));
DataOutputStream dos1=new DataOutputStream(new FileOutputStream("src/b.jpg"));
int b;
while((b=dis.read())!=-1){
dos.write(b);
}
dis.close();
dos.close();
}

3读取整个字符文件
　　String str=null;
　　while((str=br.readLine())!=-1){
　　　　System.out.println(str);
　　}
4读取整个字节文件
　　int b;
　　while((b=dis.read())!=-1){
　　　　System.out.println(b);
　　}