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Design of Campus Bicycle Rental Management System Based on SSM Framework

In view of the chaotic management of bicycle rental in colleges and the high waste rate of resources, the purpose of this paper is designing a bicycle rental management system to make it easier and more efficient for students and leasing businesses to complete bicycle rental. According to the elaboration of the system framework, the design and implementation process of the database, the design concept and use principles of the system are introduced in detail.


Introduction
At present, there is no system for bicycle rental businesses in colleges and universities to update and share bicycle information in a timely manner, resulting in low bicycle utilization rate, confusion of rental and income management. [1]This paper aims to design a campus bicycle rental management system to solve this problem eventually. The system helps students efficiently access bicycle information, making it easier for businesses to rent bicycles and manage their income. [2] In the campus bicycle rental management system, we can search all the rental bicycle information and rental records online and anytime, and can also score the rental experience. The administrator updates the user and bicycle information in a timely manner, improves the rental registration and completed orders, and checks the daily income. Super administrators manage administrator information and master all order and revenue information. In this way, management is more efficient and convenient.

Development Technique
The bicycle rental management system adopts the MVC mode, which realizes the separation of models and views, domain logic and database access, improving system flexibility and reusability and development efficiency. For the choice of system framework, we compared the common MVC framework, SSH framework and SSM framework. The decision was made to use the SSM integration framework (the integration of three open source frameworks, Spring MVC + Spring + Mybatis or SSM for short). The SSM integration framework decouples and simplifies development, enabling the design of powerful Web applications. At the same time, it is also a typical MVC framework. [3] It divides the entire system into four layers: the presentation layer (JSP and related JS), the control layer, MyBatis is an excellent data persistence framework. It writes the SQL in an xml file for easy management and optimization, avoiding almost all JDBC code and manually setting parameters and getting result sets. It also uses logical tags to control the splicing of dynamic SQL, and the result set of the completed query is automatically mapped with the java object.

Design of Function Module
The overall design of the system consists of five modules: user side, user management, administrator management, bicycle management, lease management and completed order management. User (administrator) management module includes: user registration, user information modification, and user basic information query. The background administrator (super administrator) has the function of adding users (administrators), querying all users (administrators) and managing users (administrators). Completed order management module includes: the inquiry of rental information, return time, and revenue.

The design of database structure
The bicycle rental management system operates on bicycles, bicycle rentals, orders, and the like. [5]The analysis abstracts the system into six entities: user, administrator, using, bicycle, rental registration, and completed order. The specific relationships between entities are as follows (enumeration only): Users can rent multiple bicycles, which are rented by only one user and have a one-to-many relationship.
Bicycles can be managed by multiple administrators, and administrators can operate multiple bicycles in a many-to-many relationship.
A classification can only belong to one large classification, and a large classification can have multiple small classifications. This relationship is one-to-many.

The design of logical structure
The system factors of the DBMS should be considered during the logic design phase. The process of system logic design is to convert the E-R diagram designed in the conceptual design stage to the logic structure supported by the DBMS system used. The bicycle rental management system adopts the B/S three-layer mode, which consists of a front end and a background. The front end uses Flask framework + BootStrap + JQuery + HTML + CSS and JS encapsulation. The background is mainly SpringMVC + Mybatis + Spring and Shiro.  Figure 5. System Administrator Management Process

DAO layer
According to the basic framework of the bicycle rental management system, the DAO layer is a compilation of MyBatis. The DAO layer can be understood as data stored in a database or a hard disk that can be stored for a long time. The device does not disappear in the same way as it is in memory, that is, the data is stored on the persistent device. It is focused on the system.A relatively independent aspect of achieving data persistence.
The separation of data storage logic provides an abstracted data access interface. The separation of the underlying implementation of data access allows you to switch the underlying implementation without modifying the code. The separation of resource management and scheduling enables unified resource scheduling (such as caching mechanism) at the data access layer. Data abstraction that provides more object-oriented data manipulation.

Control Layer
The Control layer (belonging to the springMVC module) is mainly responsible for the specific business module flow control. It controls the business process by calling the interface of the Service layer. The configuration of the control is also in the Spring XML configuration file. There are different controllers for the specific business process.

View layer
View layer (belongs to the springMVC module), responsible for the display of the foreground jsp page, this layer needs to be combined with the Control layer to develop. It sends the request by jsp, the controller receives the request, the processing returns, and the jsp echoes the data.

Conclusion
This paper aims to design a campus bicycle rental management system to facilitate students to rent bicycles. Through the research of SSM framework, this paper determines the development of bicycle rental system under SSM framework. From the database design to the implementation description of each logical layer of the entire framework, the process of the entire system is introduced. Finally, the system will implement user management, bicycle management, bicycle rental management, order management and other functions to make it easier for college students to rent bicycles, enabling businesses to manage bicycle rentals more effectively.