将现有的Spring应用程序转换为Spring-Boot

Question

我已配置并运行基于Spring的REST应用程序,但现在我想将其转换为Spring-Boot.

我的应用程序在带有Hibernate提供程序的JPA数据源之上使用Spring-Data-JPA:

@Configuration
@EnableJpaRepositories("foo.bar.web.repository")
@EnableTransactionManagement
public class RepositoryConfig {

    // properties ommited

    @Bean
    public DataSource dataSource() {
        BasicDataSource dataSource = new BasicDataSource();
        dataSource.setDriverClassName(className);
        dataSource.setUrl(url);
        dataSource.setUsername(userName);
        dataSource.setPassword(password);
        return dataSource;
    }

    @Bean
    public EntityManagerFactory entityManagerFactory() {
        LocalContainerEntityManagerFactoryBean factory = new LocalContainerEntityManagerFactoryBean();
        factory.setJpaVendorAdapter(new HibernateJpaVendorAdapter());
        factory.setPackagesToScan("foo.bar.web.domain");
        factory.setDataSource(dataSource());
        factory.setJpaPropertyMap(new HashMap<String, Object>() {{
            put("hibernate.dialect", dialect);
            put("hibernate.hbm2ddl.auto", hbm2ddl);
        }});
        factory.afterPropertiesSet();
        return factory.getObject();
    }

    @Bean
    public PlatformTransactionManager transactionManager() {
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(entityManagerFactory());
        return transactionManager;
    }
}

我的REST端点使用SpringMVC实现,具有以下配置:

@Configuration
@EnableWebMvc
@ComponentScan("foo.bar.web.controller")
public class MvcConfig extends WebMvcConfigurerAdapter {

    @Override
    public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
        configurer.enable();
    }

    @Bean
    public MultipartResolver multipartResolver() {
        return new CommonsMultipartResolver();
    }
}

Web初始化程序:

public class WebInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {

    @Override
    protected Class<?>[] getRootConfigClasses() {
        return new Class[]{
                ApplicationConfig.class,
                RepositoryConfig.class
        };
    }

    @Override
    protected Class<?>[] getServletConfigClasses() {
        return new Class[]{MvcConfig.class};
    }

    @Override
    protected String[] getServletMappings() {
        return new String[]{"/"};
    }
}

问题是我不想使用Spring-Boot自动配置,因为我想以最小的更改重用我现有的配置类,但我找不到正确的方法来执行此操作.我试图实现带注释的Spring-boot应用程序类@SpringBootApplication,但我并不是100%确定使用了我的配置类,因为在这种情况下我得到了java.lang.ClassCastException: org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean$$EnhancerBySpringCGLIB$$ba21071f cannot be cast to javax.persistence.EntityManagerFactory.

此外,我尝试从应用程序类中删除@EnableAutoConfiguration注释并TomcatEmbeddedServletContainerFactory手动将bean 添加到我的上下文中,但在这种情况下,嵌入式tomcat未正确配置.

如果有人能给我一个如何解决我的问题的提示,那将是很棒的.我相信我需要做的就是以某种方式用Spring-Boot配置替换我的WebInitilizer.

Answer 1

在研究中度过了一天后,我终于找到了解决问题的方法.首先,我必须修改我的entityManagerFactory()和transactionManager()bean:

    @Bean
    public LocalContainerEntityManagerFactoryBean entityManagerFactory() {
        LocalContainerEntityManagerFactoryBean factory = new LocalContainerEntityManagerFactoryBean();
        factory.setJpaVendorAdapter(new HibernateJpaVendorAdapter());
        factory.setPackagesToScan("foo.bar.web.domain");
        factory.setDataSource(dataSource());
        factory.setJpaPropertyMap(new HashMap<String, Object>() {{
            put("hibernate.dialect", dialect);
            put("hibernate.hbm2ddl.auto", hbm2ddl);
        }});
        factory.afterPropertiesSet();
        return factory;
    }

    @Bean
    public PlatformTransactionManager transactionManager() {
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(entityManagerFactory().getObject());
        return transactionManager;
    }

此外,我完全删除了我的WebInitializer课程并从中删除了@EnableWebMvc注释MvcConfig.在Spring-Boot中,不可能WebMvcConfigurerAdapter在类路径中扩展类,因为如果Spring-Boot找到它,将跳过与SpringMVC相关的所有自动配置.这是我MvcConfig班级的最终版本:

@Configuration
@ComponentScan("foo.bar.web.controller")
public class MvcConfig {

    @Bean
    public MultipartResolver multipartResolver() {
        return new CommonsMultipartResolver();
    }
}

我使用了doc中显示的Spring-Boot应用程序类的版本:

@SpringBootApplication(exclude = MultipartAutoConfiguration.class)
public class Application extends SpringBootServletInitializer {

    public static void main(String[] args) throws Exception {
        SpringApplication.run(Application.class, args);
    }

    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(Application.class);
    }
}

请注意,在我的情况下,我必须MultipartAutoConfiguration从自动配置中排除,因为我已经配置了此功能MvcConfig.Bun也可以将其保留为自动配置,但在这种情况下,我必须在application.properties配置文件中调整允许的文件大小,或者将MultipartConfigElement bean添加到我的类路径中.