The difference between the Java IO IO class and the connection

Java IO package explanation

The inheritance relationship of the IO class is as follows:

Byte stream:

Character stream:

There is no need to talk about the specific use, and roughly talk about the relationship:

Byte stream and character stream

The byte stream is to read and read the file in the form of bytes.

Suitable for operation 图片, 程序and other non-text files

The character stream is to read and read the file in the form of characters.

Suitable for operation文本文件

Byte stream

InputStreamSum OutputStreamis a base class and cannot be used directly

FileInputStreamReading byte by byte requires a lot of IO operations

BufferedInputStreamIt reads the bytes into the cache first, and then performs a one-time operation. The number of IO operations is small and the efficiency is high.

BufferedInputStreamNeed to FileInputStreambe constructed by

BufferedInputStream bis = new BufferedInputStream(new FileInputStream(f));

FileOutputStreamAnd the BufferedOutputStreamsame

Character stream

ReaderSum Writeris a base class and cannot be used directly

FileReaderAnd BufferReaderrelationships with FileInputStreamand BufferedInputStreamare similar, and even the structure is the same way

However, InputStreamReaderand BufferedReaderthe relationship is a bit more complicated
because InputStreamReadera byte character bridge, so InputStreamReaderyou need to use FileInputStreamto create, then, can be used to createBufferedReader

OutputStreamWriter, FileWriter, BufferWriterRelationship between the three above