Java - IO streams - finishing relationship (simple)

Classification IO streams

• According to dataDirection of flowDividedInput stream、Output stream

Input, output isWith respect to the code of the program we writeFor

• Input stream: from somewhere else(Local files, network resources, etc.) access to resources
• Output streams: from our programOutput elsewhere

• pressDifferent data processing unitsDividedByte stream、Character stream

Byte stream: each read (write) one byte 1Byte,Processing non-character file= "Audio, video. . .

Character stream: each read (write) two bytes 1Word = 2Byte. Processing character file = "Text

• pressDifferent functionsDividedNode Stream、Process Flow

Node Stream: read and write data to a particular place (node) or from. Such as FileInputStream　
Process Flow: is an existing connection and package stream, By flow-encapsulated call for data write.如BufferedReader。Constructor processing flow is always to bring one other stream object as an argument. A stream object after several other packaging stream.

Note：

• Only "input / output stream" can not be instantiated, must be "byte / character stream" as the connection (flow forming process), and then if necessary nested "process stream" outside
• Look at the picture below you can read up!

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Discrimination IO streams

Identification process

1. The input stream or output stream
2. Byte stream or a character stream
3. Process flow stream or node

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IO stream finishing

1. The input byte stream

• InputStream（Byte input stream） =》 FileInputStream（Node input byte stream） =》 BufferedInputStream（Processing the input stream of bytes -> process = buffer)

InputStream in = System.in;  //输入流、字节流、节点流
new BufferedInputStream(System.in); //输入流、字节流、处理流

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2. The output byte stream

• OutputStream（Byte stream output stream） =》 FileOutputStream（Node output byte stream） =》 ${\color{#ff0011}{BufferedOutputStream}}$（Output byte stream processing -> process = buffer)
• OutputStream（Byte stream output stream） =》 FileOutputStream（Node output byte stream） =》 ${\color{#ff0011}{PrintStream}}$（Output byte stream processing -> = Print Processing)

OutputStream out = System.out; //输出流、字节流、节点流  (方便看，这里向上转型，原来是PrintStream)
new BufferedOutputStream(System.out); //输出流、字节流、处理流(缓冲)
new PrintStream(System.out); //输出流、字节流、处理流(换行)

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3. Enter the character stream

• Reader（Input character stream） =》 InputStreamReader （Enter the characters node stream） =》 BufferedReader（Process stream input node）

//创建字符流实例，需要传入字节流实例
new InputStreamReader(System.in,"UTF-8"); //输入流、字符流、节点流 => 字符流有处理字符的功能
new BufferedReader(new InputStreamReader(System.in,"UTF-8")); //输入流、字符流、处理流(缓冲)

new Scanner(System.in)

Only BufferedReader can read lines readLine ()

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Output character stream

• Writer（Output character stream） =》 OutputStreamWriter（Node output byte stream） =》 BufferedWriter （An output node processing stream）
• OutputStreamWriter（Node output byte stream） =》 BufferedWriter （An output node processing stream）

//创建字符流实例，需要传入字节流实例
new OutputStreamWriter(System.out,"UTF-8"); //输出流、字符流、节点流 =》 字符流有处理字符的功能
new BufferedWriter(new OutputStreamWriter(System.out,"UTF-8")); //输出流、字符流、处理流(缓冲)
new PrintWriter(System.out);// 输出流、字符流、处理流(换行)

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to sum up

《Java-IO流》https://blog.csdn.net/sinat_37064286/article/details/86537354#1%E3%80%81%E6%B5%81%E7%9A%84%E6%A6%82%E5%BF%B5%E5%92%8C%E4%BD%9C%E7%94%A8