我正在使用 Spring 的 WebApplicationInitializer 接口以编程方式创建应用程序上下文，并使用带有 jpa 规范的 hibernate 来实现数据持久性。我将 db.properties 文件放在 src 文件夹中，在 WebAppConfig 类中添加 @PropertySource("classpath:db.properties") 。我在类路径中有以下用于休眠的 jar ......
antlr-2.7.7.jar aopalliance-1.0.jar
commons-dbcp-1.4-javadoc.jar
commons-dbcp-1.4-sources.jar
commons-dbcp-1.4.jar
commons-logging-1.1.1.jar
commons-pool-1.6-javadoc.jar
commons-pool-1.6-sources.jar
commons-pool-1.6.jar
dom4j-1.6.1.jar
hibernate-commons-annotations-4.0.1.Final.jar
hibernate-core-4.1.9.Final.jar
hibernate-entitymanager-4.1.9.Final.jar
hibernate-jpa-2.0-api-1.0.1.Final.jar
javassist-3.17.1-GA.jar
jboss-logging-3.1.0.GA.jar
jta-1.1.jar
mysql-connector-java-5.1.6-bin.jar
网络初始化程序类代码
package com.genesis.init;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRegistration.Dynamic;
import org.springframework.web.WebApplicationInitializer;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;
public class Initializer implements WebApplicationInitializer {
// gets invoked automatically when application starts up
public void onStartup(ServletContext servletContext)
throws ServletException {
// Create ApplicationContext. I'm using the
// AnnotationConfigWebApplicationContext to avoid using beans xml files.
AnnotationConfigWebApplicationContext ctx = new AnnotationConfigWebApplicationContext();
ctx.register(WebAppConfig.class);
// Add the servlet mapping manually and make it initialize automatically
Dynamic servlet = servletContext.addServlet("dispatcher",
new DispatcherServlet(ctx));
servlet.addMapping("/");
servlet.setLoadOnStartup(1);
}
}
WebAppConfig 代码
package com.genesis.init;
import java.util.Map;
import javax.sql.DataSource;
import org.apache.commons.dbcp.BasicDataSource;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.core.env.Environment;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.support.OpenEntityManagerInViewInterceptor;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
import org.springframework.web.servlet.view.InternalResourceViewResolver;
@Configuration
// specifies this class as configuration
@ComponentScan("com.genesis")
// specifies which package to scan
@EnableWebMvc
// enable spring web mvc to use annotation
@PropertySource("classpath:db.properties")
// plugs in property file which located in the resource folder.
@EnableTransactionManagement
// enables Spring’s annotation-driven transaction management capability.
public class WebAppConfig extends WebMvcConfigurerAdapter {
@Autowired
private Environment env;
// Tell SpingMVC where to find view scripts
@Bean
public InternalResourceViewResolver viewResolver() {
InternalResourceViewResolver resolver = new InternalResourceViewResolver();
resolver.setPrefix("/WEB-INF/views/");
resolver.setSuffix(".jsp");
return resolver;
}
// Enable serving static resources even when DispatcherServlet is mapped to
@Override
public void configureDefaultServletHandling(
DefaultServletHandlerConfigurer configurer) {
configurer.enable();
}
// Enable accessing entityManager from view scripts. Required when using
// lazy loading
@Override
public void addInterceptors(InterceptorRegistry registry) {
OpenEntityManagerInViewInterceptor viewInterceptor = new OpenEntityManagerInViewInterceptor();
viewInterceptor.setEntityManagerFactory(entityManagerFactory().getObject());
registry.addWebRequestInterceptor(viewInterceptor);
}
//Set up dataSource to be used by Hibernate. Also make sure the connection doesn't go down
@Bean
public DataSource getDataSource() {
BasicDataSource dataSource = new BasicDataSource();
dataSource.setUrl(env.getProperty("url"));
dataSource.setDriverClassName(env.getProperty("driver"));
dataSource.setUsername(env.getProperty("user"));
dataSource.setPassword(env.getProperty("pass"));
dataSource.setValidationQueryTimeout(5);
return dataSource;
}
//Set up JPA and transactionManager
@Bean
public LocalContainerEntityManagerFactoryBean entityManagerFactory() {
LocalContainerEntityManagerFactoryBean emf = new LocalContainerEntityManagerFactoryBean();
emf.setDataSource(getDataSource());
emf.setPackagesToScan("com.genesis.model");
// let Hibernate know which database we're using.
// note that this is vendor specific, not JPA
Map<String, Object> opts = emf.getJpaPropertyMap();
opts.put("hibernate.dialect", env.getProperty("hibernate.dialect"));
HibernateJpaVendorAdapter va = new HibernateJpaVendorAdapter();
emf.setJpaVendorAdapter(va);
return emf;
}
//Let us use PlatformTransactionManager directly to implement programmatic approach to implement transactions
//To start a new transaction you need to have a instance of TransactionDefinition
@Bean
public PlatformTransactionManager transactionManager(){
JpaTransactionManager transactionManager=new JpaTransactionManager();
transactionManager.setEntityManagerFactory(entityManagerFactory().getObject());
return transactionManager();
}
}
数据库属性文件为。
driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/test
hibernate.dialect=org.hibernate.dialect.MySQLDialect
user=root
pass=iems1234
show_sql=true
packages.to.scan=com.genesis.model
控制台输出是…………
SEVERE: Context initialization failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class com.genesis.init.WebAppConfig: Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build EntityManagerFactory
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1507)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:539)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:299)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:295)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1145)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:922)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:493)
at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:658)
at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:512)
at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:466)
at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
at javax.servlet.GenericServlet.init(GenericServlet.java:160)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1267)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1084)
at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:5027)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5314)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.StandardContext.reload(StandardContext.java:3920)
at org.apache.catalina.loader.WebappLoader.backgroundProcess(WebappLoader.java:426)
at org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1345)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1530)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1540)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1540)
at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1519)
at java.lang.Thread.run(Thread.java:722)
Caused by: javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build EntityManagerFactory
at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:915)
at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:890)
at org.hibernate.ejb.HibernatePersistence.createContainerEntityManagerFactory(HibernatePersistence.java:74)
at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:293)
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:317)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1566)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1503)
... 27 more
Caused by: org.hibernate.HibernateException: Dialect class not found: org.hibernate.dialect.MySQLDialect
at org.hibernate.service.jdbc.dialect.internal.DialectFactoryImpl.constructDialect(DialectFactoryImpl.java:76)
at org.hibernate.service.jdbc.dialect.internal.DialectFactoryImpl.buildDialect(DialectFactoryImpl.java:64)
at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:170)
at org.hibernate.service.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:75)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:159)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:131)
at org.hibernate.cfg.SettingsFactory.buildSettings(SettingsFactory.java:77)
at org.hibernate.cfg.Configuration.buildSettingsInternal(Configuration.java:2283)
at org.hibernate.cfg.Configuration.buildSettings(Configuration.java:2279)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1748)
at org.hibernate.ejb.EntityManagerFactoryImpl.<init>(EntityManagerFactoryImpl.java:94)
at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:905)
... 33 more
Caused by: org.hibernate.service.classloading.spi.ClassLoadingException: Unable to load class [org.hibernate.dialect.MySQLDialect ]
at org.hibernate.service.classloading.internal.ClassLoaderServiceImpl.classForName(ClassLoaderServiceImpl.java:141)
at org.hibernate.service.jdbc.dialect.internal.DialectFactoryImpl.constructDialect(DialectFactoryImpl.java:73)
... 44 more
Caused by: java.lang.ClassNotFoundException: Could not load requested class : org.hibernate.dialect.MySQLDialect
at org.hibernate.service.classloading.internal.ClassLoaderServiceImpl$1.findClass(ClassLoaderServiceImpl.java:99)
at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:266)
at org.hibernate.service.classloading.internal.ClassLoaderServiceImpl.classForName(ClassLoaderServiceImpl.java:138)
... 45 more