Exercise4

网上文件管理系统：myeclipse开发的，可以上传下载文件，struts2框架，附带mysql数据库(Online document management system: myeclipse developed can upload and download files, struts2 framework with mysql database)

本代码只是简单实现了办公系统的一小部分，使用struts等框架，只适合初学者参考。(This code simply implements a small part of office systems, such as using the struts framework, reference is only suitable for beginners.)

Calculates if the brackets in a sentence are correctly close. Input consists, one per line, sentences with brackets, and output say YES if its correctly close, or NO int if its not saying where is the error. Input: ()[]<>(**) (*) (ASA Output: YES NO 2 NO 4

黄鳄鱼提供的完整Hilbert Huang Transform程序，java源码，含EMD，EMD1，EMD2，频谱，边际频谱，图形界面，测试例程等。(complete java source code for Hilbert- Huang Transform, this package is a official version provide by Professor NordenE.Huang，all class just as EMD，EMD1，EMD2，spectrum，chart etc. are included in it.)

jdbcUtils小工具，用于实现数据库的方便连接，本地执行已通过(jdbcUtils , Convenient for realization of the connection，Local execution has passed )

Javacv java computer version its used in the video streaming process.

说明：  SpringBoot + Vue前后端分离的航天机票管理系统，使用MySQL作为数据库(Spring boot + Vue front and back end separation of space flight ticket management system, using MySQL as the database)

一封家书。实现类的集成以及多态性，很好的练习题目。实现家书书写版本(A letter home. Achieve integration and polymorphism, practice questions. Letter writing version)

JAVA 文件操作 包括文件的复制 创建文件 显示文件等等操作(JAVA file copy file to create the file display file etc.)

说明：  网络版JAVA版飞机大战，自己在学习JAVA网络开发时写的小栗子(Network version JAVA version of the aircraft war,Xiao Chestnut Written by myself in Learning JAVA Network Development)