There are not many things at work recently, and I feel that the improvement of myself is not very high.
Under the recommendation of the great gods in the group, it is better to look at the source code of JDK to improve your basic knowledge of java. The main thing to learn is the source code of JDK and learn together with java programming ideas.
The short-term goal is to learn the methods of JDK tools, and then learn together with java programming ideas.