hibernate基础简单入门1---helloword

Posted 2020-09-07 智云

1:目录结果

2:实体类(student.java)

package com.www.entity;
public class Student {
private int id;
private String    name;
private int age;

public int getId() {
    return id;
}
public void setId(int id) {
    this.id = id;
}
public String getName() {
    return name;
}
public void setName(String name) {
    this.name = name;
}
public int getAge() {
    return age;
}
public void setAge(int age) {
    this.age = age;
}
}

3:实体类映射表(Student.hbm.xml)

<!DOCTYPE hibernate-mapping PUBLIC
        "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
    <class name="com.www.entity.Student" table="stu_tab2">
        <id name="id" column="stu_id">
            <generator class="native"></generator>
        </id>
        <property name="name" column="stu_name"></property>
        <property name="age" column="stu_age"></property>
    </class>
</hibernate-mapping>

4:hibernate配置文件(hibernate.cfg.xml)

<!DOCTYPE hibernate-configuration PUBLIC
    "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
    "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
    <!--配置mysql数据库连接参数-->
    <property name="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</property>
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="hibernate.connection.url">jdbc:mysql:///hibernate</property>
<property name="hibernate.connection.username">root</property>
<property name="hibernate.connection.password"></property>
<mapping resource="com/www/entity/Student.hbm.xml"/>
</session-factory>
</hibernate-configuration>

5:日志文件(log4j.properties)

log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n
### direct messages to file hibernate.log ###
#log4j.appender.file.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n
### set log levels - for more verbose logging change \'info\' to \'debug\' ###
log4j.rootLogger=warn, stdout
#log4j.logger.org.hibernate=info
log4j.logger.org.hibernate=debug
log4j.logger.org.hibernate.type=info
### log schema export/update ###
log4j.logger.org.hibernate.tool.hbm2ddl=debug

6：单元测试文件(StudentTest.java)

package com.www.test;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.Test;
import com.www.entity.Student;
public class StudentTest {
    // 1.自动创建数据库表,不用创建表，它能自动帮你创建表。
    @Test
    public void createTable() {
        Configuration configuration = new Configuration().configure();
        SchemaExport se = new SchemaExport(configuration);
        se.create(true, true);

    }
    //添加
    @Test
    public void add() {
        Configuration cfg = new Configuration().configure();
        StandardServiceRegistryBuilder ssrb = new StandardServiceRegistryBuilder().applySettings(cfg.getProperties());
        ServiceRegistry service = ssrb.build();
        SessionFactory factory = cfg.buildSessionFactory(service);

        Session session = factory.openSession();
        Transaction tx = session.beginTransaction();
        Student stu = new Student();
        stu.setAge(20);
        stu.setName("wowo");
        try {
            session.save(stu);
            tx.commit();
        } catch (Exception e) {
            // TODO: handle exception
            tx.rollback();
        } finally {
            session.close();
        }
    }
    //查看
@Test
    public void get() {
        Configuration cfg = new Configuration().configure();
        StandardServiceRegistryBuilder ssrb = new StandardServiceRegistryBuilder().applySettings(cfg.getProperties());
        ServiceRegistry service = ssrb.build();
        SessionFactory factory = cfg.buildSessionFactory(service);

        Session session = factory.openSession();
        Transaction tx = session.beginTransaction();
        try {
            Student stu = (Student) session.get(Student.class, 1);
            System.out.println(stu.getId() + stu.getName() + stu.getAge());
            tx.commit();
        } catch (Exception e) {
            // TODO: handle exception
            tx.rollback();
        } finally {
            session.close();
        }
    }

}

7:另一种hibernate连接数据库的配置文件(hibernate.properties)

目录结构:

hibernate.dialect=org.hibernate.dialect.MySQLDialect
hibernate.connection.driver_class=com.mysql.jdbc.Driver
hibernate.connection.url=jdbc:mysql://localhost:3306/hibernate
hibernate.connection.username=root
hibernate.connection.password=
hibernate.show_sql=true

 

总结:hibernate创建基本都是这六步，下面的记死

Configuration cfg = new Configuration().configure();
        StandardServiceRegistryBuilder ssrb = new StandardServiceRegistryBuilder().applySettings(cfg.getProperties());
        ServiceRegistry service = ssrb.build();
        SessionFactory factory = cfg.buildSessionFactory(service);

        Session session = factory.openSession();
        Transaction tx = session.beginTransaction();