Question

我在Spring启动应用程序的application.properties文件中配置了hibernate属性。

application.properties

#hibernate config
spring.jpa.database-platform=org.hibernate.dialect.Oracle10gDialect
spring.datasource.url=<db_url>
spring.datasource.username=<username>
spring.datasource.password=<password>
spring.datasource.driver-class-name=oracle.jdbc.OracleDriver
# Show or not log for each sql query
spring.jpa.show-sql = true
# Naming strategy
spring.jpa.hibernate.naming-strategy = org.hibernate.cfg.ImprovedNamingStrategy     

# ThymeLeaf
spring.thymeleaf.cache= false
spring.thymeleaf.mode=LEGACYHTML5

当我尝试将会话作为

时，我收到错误

Configuration configuration = new Configuration();
configuration.configure("application.properties");
StandardServiceRegistryBuilder ssrb = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties());
SessionFactory sessionFactory = configuration.buildSessionFactory(ssrb.build());
Session session = sessionFactory.openSession();

错误：

Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.hibernate.HibernateException: 
Could not parse configuration: application.properties] with root cause

org.dom4j.DocumentException: Error on line 1 of document  : Content is not allowed in prolog. Nested exception: Content is not allowed in prolog.

我认为它在类路径中也期待hibernate.cfg.xml个文件？

有什么方法我只能使用application.properties或者我必须将所有与休眠相关的属性移动到hibernate.cfg.xml或hibernate.properties文件？

getSelectedStudents

public List getSelectedStudents(){
    final EntityManagerFactory emf = null;
    EntityManager em = emf.createEntityManager();

    Query q = em.createNativeQuery("SELECT s.student_id, s.first_name, s.last_name, s.city FROM Student s "
                                    + "where s.city=:city and s.last_name = :lname", Student.class);
    q.setParameter("city", "London");
    q.setParameter("lname", "Rizwan");

    List<Student> students = q.getResultList();

    for (Student s : students) {
        System.out.println("Student "
                + s.getFirstName()
                + " "
                + s.getLastName());
    }

    return students;
}

错误2：

Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is java.lang.NullPointerException] with root cause

java.lang.NullPointerException: null
    at com.school.service.StudentServiceImplementation.getSelectedStudents(StudentServiceImplementation.java:69) ~[classes/:na]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_77]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_77]

编辑：建议使用实体管理器，我添加了getSelectedStudents方法。我仍在EntityManager em = emf.createEntityManager();收到错误有关详细信息，请参阅错误2。

Answer 1

如果你在带有spring-autoconfigure的tandum中使用spring-boot，你可以简单地将Hibernate库放到你的类路径上，spring会自动连接Hibernate。您需要做的就是在application.properties文件中提供一些spring jpa配置设置，然后就完成了。

如果您想避免使用spring-autoconfigure，那么您需要添加一个构造LocalContainerEntityManagerFactoryBean，JpaTransactionManager和DataSource的配置类。

在任何一种情况下，要在您的应用程序中使用JPA，您只需要在存储库或服务类中添加带注释的属性，以便为EntityManager获取实例，如下所示：

@PersistentContext
private EntityManager entityManager;

Spring会确保为您注入此内容，您的代码只需根据需要使用它。

Answer 2

实施例。在配置类中，您需要调用@PropertySources并声明环境变量。

    import java.util.Properties;

    import javax.sql.DataSource; 
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.context.annotation.PropertySource;
    import org.springframework.context.annotation.PropertySources;
    import org.springframework.core.env.Environment; 
    import org.springframework.orm.hibernate4.LocalSessionFactoryBean; 
    import org.springframework.jndi.JndiTemplate;

    @Configuration
    @PropertySources(value = {@PropertySource("classpath:application.properties") })
    public class DataBaseConfig {

        @Autowired
        private Environment environment;

        @Bean(name = "dataSource")
        public DataSource dataSource() {
            ..........
            return dataSource;
        }



        @Bean
        public LocalSessionFactoryBean getSessionFactory() {
            LocalSessionFactoryBean asfb = new LocalSessionFactoryBean();
            asfb.setDataSource(dataSource());
            asfb.setHibernateProperties(getHibernateProperties());
            asfb.setPackagesToScan(new String[] { "your package domain class" });
            return asfb;
        }



        Properties getHibernateProperties() {
            Properties properties = new Properties();
            properties.put("schema", environment.getProperty("JNDI.SCHEMA"));
            properties.put("hibernate.dialect", environment.getProperty("HIBERNATE.DIALECT.PGSQL"));
            properties.put("hibernate.show_sql", environment.getProperty("HIBERNATE.SQL.SHOW"));
            properties.put("hibernate.format_sql", environment.getProperty("HIBERNATE.SQL.FORMAT"));
            properties.put("hibernate.hbm2ddl.auto", environment.getProperty("HIBERNATE.HBM2DDL.AUTO"));
            properties.put("hibernate.default_schema", environment.getProperty("JNDI.SCHEMA"));
            properties.put("hibernate.use_sql_comments", environment.getProperty("HIBERNATE.SQL.COMMENTS"));
            properties.put("hibernate.connection.CharSet", environment.getProperty("HIBERNATE.CHARSET"));
            properties.put("hibernate.generate_statistics", environment.getProperty("HIBERNATE.STATISTICS"));
            properties.put("hibernate.connection.autocommit", environment.getProperty("HIBERNATE.AUTOCOMMIT"));
            properties.put("hibernate.connection.useUnicode", environment.getProperty("HIBERNATE.UNICODE"));
            properties.put("hibernate.enable_lazy_load_no_trans", environment.getProperty("HIBERNATE.ENABLED.LAZY"));
            properties.put("hibernate.connection.characterEncoding", environment.getProperty("HIBERNATE.ENCODING"));
            return properties;

        }


    }

在你＆＃34; application.properties＆＃34;文件有这个。

        ################ CONFIGURACION HIBERNATE ################
        HIBERNATE.SEARCH.DEFAULT.PROVIDER=hibernate.search.default.directory_provider
        HIBERNATE.DIALECT.MYSQL=org.hibernate.dialect.MySQL5InnoDBDialect
        HIBERNATE.DIALECT.MSSQL=org.hibernate.dialect.SQLServerDialect
        HIBERNATE.DIALECT.PGSQL=org.hibernate.dialect.PostgreSQLDialect
        HIBERNATE.CACHE.SECONDLEVEL=false
        HIBERNATE.CACHE.QUERYCACHE=false
        HIBERNATE.ENABLED.LAZY=hibernate.enable_lazy_load_no_trans
        HIBERNATE.HBM2DDL.AUTO=none   
        HIBERNATE.SQL.COMMENTS=false
        HIBERNATE.SQL.FORMAT=false
        HIBERNATE.STATISTICS=false
        HIBERNATE.AUTOCOMMIT=true
        HIBERNATE.SQL.SHOW=true
        HIBERNATE.ENCODING=utf8
        HIBERNATE.CHARSET=utf8 
        HIBERNATE.UNICODE=true

Spring启动应用程序中的application.properties vs hibernate.cfg.xml

2 个答案: