Introduction to the UJO ORM framework and its application in the Java class library
Introduction to the UJO ORM framework and its application in the Java class library
Overview:
UJO ORM (Object-Relational Mapping) is a widely used ORM framework in the Java library to simplify the mapping relationship between the Java object and the relationship database.
ORM profile:
ORM is a programming technology that is used to map the object model (class, object) with the tables and fields in the relationship database to achieve the persistence storage of the object.The ORM framework can automatically map the attributes of the object with the table field of the database, and provide convenient operating interfaces to hide the tedious SQL statement writing process.
UJO ORM framework features:
1. Simple and easy to use: The UJO ORM framework provides simple API and configuration options, so that developers can easily persist Java objects into the database.
2. Flexibility: The UJO ORM framework supports a variety of databases, such as MySQL, Oracle, etc., and provides rich configuration options, which can be flexibly configured according to project needs.
3. Performance optimization: The UJO ORM framework uses an optimized query statement to reduce the number of database access and improve the performance of the program.
4. Affairs management: The UJO ORM framework provides transaction management functions to ensure the consistency and integrity of the data.
5. Tool support: The UJO ORM framework also provides some auxiliary tools, such as the code generator and database migration tool to help developers better use the framework.
The application of the UJO ORM framework in the Java library:
1. Data persistence: In Java applications, using UJO ORM can easily endure Java objects into the database.By mapping the Java object with the database table, developers can use object -oriented methods to operate data without writing SQL statements directly.
2. Data query: The UJO ORM framework provides a wealth of query grammar and API, which can easily perform data query operations.Developers can use object -oriented methods to build query conditions and obtain data results that meet the conditions.
3. Affairs management: UJO ORM framework supports transaction management. Developers can control the submission or rollback of transactions through the API provided by the framework to ensure the consistency and integrity of the data.
4. Cache support: The UJO ORM framework also provides cache support to improve the query performance.Developers can configure the cache strategy and obtain the results from the cache during the query to reduce the number of database access.
5. Data verification: The UJO ORM framework supports the data verification function. Developers can ensure the effectiveness and integrity of the data through configuring verification rules.
Below is a sample code using the UJO ORM framework:
import org.unitorm.DataStore;
import org.unitorm.Domain;
import org.unitorm.Entity;
import org.unitorm.Seq;
public class User extends Entity {
private String name;
private int age;
// Getters and setters
public static void main(String[] args) {
DataStore dataStore = new DataStore("jdbc:mysql://localhost:3306/mydatabase", "username", "password");
Domain<User> userDomain = new Domain<>(dataStore, User.class);
// Create a user object
User user = new User();
user.setName ("Zhang San");
user.setAge(25);
// Save the user object to the database
userDomain.save(user);
// Inquiry users with age greater than equal to 20
Seq<User> users = userDomain.find("age >= ?", 20);
// Output query results
for (User u : users) {
System.out.println(u.getName() + ", " + u.getAge());
}
}
}
The above code example shows how to use the UJO ORM framework to mappore and operate the Java object and the database table.
First, create a physical class `user` and inherit with the` Entity` class, indicating that this class needs to perform persistent operations.
Then, set the database connection information by creating the `datastore` object.
Then, create a `domain` object, specify data storage and physical class.
Subsequently, you can create a user object, set the attribute value, and save it to the database through the `save ()` method.
Finally, use the `Find ()` method to query users with a age of 20 and output the query results.
It should be noted that using the UJO ORM framework requires configured database connection information in advance, including database URL, username and password.In addition, more configurations can be performed as needed, such as cache strategies and transaction management.
Summarize:
The UJO ORM framework is an ORM framework widely used in the Java class library, which can simplify the mapping relationship between the Java object and the relationship database.Through the UJO ORM framework, developers can use object -oriented methods to operate data without writing tedious SQL statements.In Java applications, the application of the UJO ORM framework has functions such as data persistence, data inquiry, transaction management, cache support, and data verification.By using the UJO ORM framework, developers can improve development efficiency, reduce code complexity, and ensure the consistency and integrity of data.
