Hibernate_HelloWord
Hibernate操作步骤
1.新建项目 2.加jar包 3.写XML配置文件hibernate.cfg.xml 4.写log4j.properties日志文件 5.在MySql数据库中建student表 6.建Student实体类(先建表后建类) 7.写XML映射文件Student.hbm.xml,或者Annotation映射语句 8.在hibernate.cfg.xml中添加相应mapping 9.写测试类main,或者Junit测试类(项目右键-->“New”-->“Junit Test Case”)
HelloWorld小程序----XML映射文件
1.新建项目
2.加jar包。此处列出的jar包是Hibernate所需的全部jar包,在此项目中并不是全部需要
将如下jar包封装进一个User Library,名为hibernate antlr-2.7.6.jar c3p0-0.9.1.jar commons-collections-3.1.jar dom4j-1.6.1.jar hibernate3.jar hibernate-annotations.jar hibernate-commons-annotations.jar hibernate-jpa-2.0-api-1.0.0.Final.jar javassist-3.12.0.GA.jar jta-1.1.jar junit-4.10.jar log4j-1.2.14.jar mysql-connector-java-5.1.7-bin.jar slf4j-api-1.6.1.jar slf4j-log4j12-1.6.1.jar
3.hibernate.cfg.xml配置文件。其中<mapping/>在步骤8中设置
<?xml version=‘1.0‘ encoding=‘utf-8‘?> <!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> <!-- Database connection settings --> <property name="connection.driver_class">com.mysql.jdbc.Driver</property> <property name="connection.url">jdbc:mysql://localhost/test</property> <property name="connection.username">root</property> <property name="connection.password">root</property> <!-- JDBC connection pool 连接池 --> <!-- <property name="connection.pool_size">1</property> --> <!-- SQL dialect 方言--> <property name="dialect">org.hibernate.dialect.MySQLDialect</property> <!-- 当前session上下文 . thread:当前线程;jta:(java transaction api) --> <property name="current_session_context_class">thread</property> <!-- Disable the second-level cache 去掉二级缓存 --> <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property> <!-- Echo all executed SQL to stdout 显示sql语句--> <property name="show_sql">true</property> <!-- Drop and re-create the database schema on startup 常用选项:create和update --> <property name="hbm2ddl.auto">update</property> <mapping resource="com/hibernate/model/Student.hbm.xml"/> <!-- <mapping class="com.hibernate.model.Student"/> --> </session-factory> </hibernate-configuration>
4.log4j.properties日志文件
### direct log messages to stdout ### 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=org.apache.log4j.FileAppender #log4j.appender.file.File=hibernate.log #log4j.appender.file.layout=org.apache.log4j.PatternLayout #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 ### log HQL query parser activity #log4j.logger.org.hibernate.hql.ast.AST=debug ### log just the SQL #log4j.logger.org.hibernate.SQL=debug ### log JDBC bind parameters ### #log4j.logger.org.hibernate.type=info #log4j.logger.org.hibernate.type=debug ### log schema export/update ### #log4j.logger.org.hibernate.tool.hbm2ddl=debug ### log HQL parse trees #log4j.logger.org.hibernate.hql=debug ### log cache activity ### #log4j.logger.org.hibernate.cache=debug ### log transaction activity #log4j.logger.org.hibernate.transaction=debug ### log JDBC resource acquisition #log4j.logger.org.hibernate.jdbc=debug ### enable the following line if you want to track down connection ### ### leakages when using DriverManagerConnectionProvider ### #log4j.logger.org.hibernate.connection.DriverManagerConnectionProvider=trace
5.在数据库中建表
建表可以在数据库中手动建,也可以通过运行程序自动建立。
此处自动建表
6.建Student实体类
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; } }
7.Student.hbm.xml映射文件
<?xml version="1.0"?> <!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.hibernate.model.Student" dynamic-update="true"> <id name="id"> <generator class="native"></generator> <!-- generator设置其id自增 --> </id> <!-- id指的是相应表的主键 --> <property name="name"></property> <property name="age"></property> </class> </hibernate-mapping>
8.在hibernate.cfg.xml中添加相应mapping
9.写测试类main
public class StudentTest { public static void main(String[] args) { Student s = new Student(); s.setName("s3"); s.setAge(10); SessionFactory sf = new Configuration().configure().buildSessionFactory(); Session session = sf.getCurrentSession(); session.beginTransaction(); session.save(s); session.getTransaction().commit(); sf.close(); } }
程序到此结束,运行后,会自动在数据库创建student表,并将对象s存入student表中。
HelloWorld小程序----Annotation映射语句
步骤1-5同上
6,7.建实体类,添加Annotation注解
@Entity //表示这是一个实体类,和数据库中的某个表是对应的 public class Teacher { private int id; private String name; private int age; @Id //主键 @GeneratedValue //ID生成策略,默认为AUTO 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; } }
8.在hibernate.cfg.xml中添加相应mapping,如下
<mapping class="com.hibernate.model.Student"/>
9.写测试类
测试类有很多种方式
a)见上文测试类main
b)创建一个HibernateUtil辅助类 ,然后再建测试类main
public class HibernateUtil { private static SessionFactory sf = buildSessionFactory(); private static SessionFactory buildSessionFactory() { return new Configuration().configure().buildSessionFactory(); } public static SessionFactory getSessionFactory() { return sf; } }
public class StudentTest { public static void main(String[] args) { Student s = new Student(); s.setName("lisi"); s.setAge(18); SessionFactory sf = HibernateUtil.getSessionFactory(); Session session = sf.getCurrentSession(); session.beginTransaction(); session.save(s); session.getTransaction().commit(); sf.close(); } }
c)建Junit测试类
项目右键-->“New”-->“Junit Test Case”,输入类名,然后完善test方法
public class StudentTest_Junit { private static SessionFactory sf = null; @BeforeClass public static void beforeClass(){ sf = new Configuration().configure().buildSessionFactory(); } @AfterClass public static void afterClass(){ sf.close(); } @Test public void test() { Student s = new Student(); s.setName("wangwu"); s.setAge(23); Session session = sf.getCurrentSession(); session.beginTransaction(); session.save(s); session.getTransaction().commit(); } }
程序到此结束,运行后,会自动在数据库创建student表,并将对象s存入student表中。
郑重声明:本站内容如果来自互联网及其他传播媒体,其版权均属原媒体及文章作者所有。转载目的在于传递更多信息及用于网络分享,并不代表本站赞同其观点和对其真实性负责,也不构成任何其他建议。