(The Handbook of Java Common Algorithms is divided into three chapters, including 13 chapters, which respectively introduce the algorithm foundation, algorithm use and algorithm interview questions. Firstly, the algorithm is introduced, and then the data structure and basic algorithm idea are analyzed; Then, the application of the algorithm in sorting, searching, mathematical calculation, number theory, historical interesting questions, games, cryptography and other fields is explained in detail; Finally, some common interview questions of the algorithm are listed.)