JDK source code analysis
The wrapper class in the IO stream uses the decorator pattern.
BufferedInputStream，
BufferedOutputStream，
BufferedReader，
BufferedWriter
Let's take BufferedWriter as an example to illustrate, first look at how to use BufferedWriter
It really feels like decorator mode to use, let's look at their structure:
summary:
BufferedWriter uses the decorator pattern to enhance the Writer sub-implementation class, adds a buffer, and improves the efficiency of writing data.