java中IO整理

1.将数据从外存中读取到内存中的称为输入流，将数据从内存写入外存中的称为输出流。

2.标准的文件读写程序：

public static void main(String[] args) {
File file = new File("Test.txt");
try {
FileInputStream fis = new FileInputStream(file);
InputStreamReader isr = new InputStreamReader(fis, "gbk");
BufferedReader br = new BufferedReader(isr);
String line;
while((line=br.readLine()) != null){
System.out.println(line);
}
br.close();
isr.close();
fis.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
File nfile = new File("new_Test.txt");
try {
FileOutputStream fos = new FileOutputStream(nfile);
OutputStreamWriter osw = new OutputStreamWriter(fos, "gbk");
BufferedWriter bw = new BufferedWriter(osw);
bw.write("你是不是我写入的");
bw.close();
osw.close();
fos.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

}

3.父到子：Object->io.Reader(字符流)->io.InputStreamReader->io.FileReader

  父到子：Object->io.Reader（字符流）->io.BufferedReader

  父到子：Object->io.InputStream（字节流）->FilterInputStream->io.BufferedInputStream

  父到子：Object->io.InputStream（字节流）->io.FileInputStream(获得输入的字节)