JPA：对象不是已知的实体类型。完全不知道如何使用模块化域（持久性）项目配置 Spring 网络应用程序

Question

我正在使用 Spring 框架创建一个 Web 应用程序，并尝试以模块化方式进行。使用 NetBeans，我有 2 个项目：一个包含我的应用程序逻辑，另一个包含我的实际 Web 应用程序。
在我的域应用程序中，我有使用 JPA 的 DAO，并且也在那里进行了测试。现在，当我试图在我的 Spring 模块中重用这些 classes 时，问题就出现了。我对这两个项目都使用 Maven，并在我的 Spring 模块中添加了对我的域项目的依赖。我对如何配置这一切感到很困惑，这是我第一次制作这样的应用程序，事实上，也使用 Spring 和 JPA。同样奇怪的是，当我的电脑重新启动时我第一次启动服务器时，它会工作，但随后重新启动服务器将导致 JPA 层不再工作。

当我试图保留我的对象时出现错误：

Object: com.ucll.lolwithbuddies.domain.League@19f is not a known entity type.

我尝试将 JAR 用于我的持久性模块并将其放入我的 Web 应用程序的 WEB-INF/lib 文件夹中，但随后出现以下错误：

javax.persistence.PersistenceException: No Persistence provider for EntityManager named LoLWithBuddiesPU

persistence.xml 位于 LoLWithBuddies/src/main/resources/META-INF:

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
 <persistence-unit name="LoLWithBuddiesPU" transaction-type="RESOURCE_LOCAL">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<class>com.ucll.lolwithbuddies.domain.League</class>
<class>com.ucll.lolwithbuddies.domain.Membership</class>
<class>com.ucll.lolwithbuddies.domain.Player</class>
<exclude-unlisted-classes>false</exclude-unlisted-classes>
<properties>
  <property name="javax.persistence.jdbc.url" value="jdbc:derby://localhost:1527/LoLWithBuddies;create=true"/>
    <property name="javax.persistence.jdbc.user" value="app"/>
    <property name="javax.persistence.jdbc.driver" value="org.apache.derby.jdbc.ClientDriver"/>
    <property name="javax.persistence.jdbc.password" value="app"/>
    <property name="javax.persistence.schema-generation.database.action" value="drop-and-create"/>
</properties>
 </persistence-unit>
</persistence>

LoLWithBuddies/src/main/java/com/ucll/LoLWithBuddies/db/RelationalLeagueDB:

package com.ucll.lolwithbuddies.db;

import com.ucll.lolwithbuddies.domain.League;
import java.util.List;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.Query;

/**
 *
 * @author Christophe
 */
public class RelationalLeagueDB implements LeagueDB {

    private EntityManagerFactory factory;
    private EntityManager manager;

    public RelationalLeagueDB(String name) {
        factory = Persistence.createEntityManagerFactory(name);
    }

    @Override
    public League get(long id) throws DBException {
        try {
            manager = factory.createEntityManager();
            League league = manager.find(League.class, id);
            if (league == null) {
                throw new DBException("League not found");
            }
            return league;
        } catch (Exception e) {
            throw new DBException(e.getMessage());
        } finally {
            manager.close();
        }
    }

    @Override
    public List<League> getAll() throws DBException {
        try {
            manager = factory.createEntityManager();
            Query query = manager.createQuery("select l from League l");
            return query.getResultList();
        } catch (Exception e) {
            throw new DBException(e.getMessage());
        } finally {
            manager.close();
        }
    }

    @Override
    public void update(League league) throws DBException {
        try {

            manager = factory.createEntityManager();

            //update in memory reflected to database inside transaction
            League leagueInDB = manager.find(League.class, league.getId());

            manager.getTransaction().begin();
            leagueInDB.setName(league.getName());
            manager.flush();
            manager.getTransaction().commit();

        } catch (Exception e) {
            throw new DBException(e.getMessage());
        } finally {
            manager.close();
        }
    }

    @Override
    public void delete(long id) throws DBException {
        try {
            manager = factory.createEntityManager();
            League league = manager.find(League.class, id);
            manager.getTransaction().begin();
            manager.remove(league);
            manager.flush();
            manager.getTransaction().commit();
        } catch (Exception e) {
            throw new DBException(e.getMessage());
        } finally {
            // manager.close();
        }
    }

    @Override
    public void add(League item) throws DBException {
        try {
            manager = factory.createEntityManager();
            manager.getTransaction().begin();
            manager.persist(item);
            manager.flush();
            manager.getTransaction().commit();
        } catch (Exception e) {
            throw new DBException(e.getMessage());
        } finally {
            manager.close();
        }
    }

    @Override
    public void closeConnection() throws DBException {
        factory.close();
    }
}

pom.xml 持久性项目：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.ucll</groupId>
    <artifactId>LoLWithBuddies</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>jar</packaging>
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.11</version>
            <scope>test</scope>
            <type>jar</type>
        </dependency>
        <dependency>
            <groupId>org.eclipse.persistence</groupId>
            <artifactId>eclipselink</artifactId>
            <version>2.5.2</version>
        </dependency>
        <dependency>
            <groupId>org.eclipse.persistence</groupId>
            <artifactId>org.eclipse.persistence.jpa.modelgen.processor</artifactId>
            <version>2.5.2</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.apache.derby</groupId>
            <artifactId>derbyclient</artifactId>
            <version>10.12.1.1</version>
        </dependency>
        <dependency>
            <groupId>javax.validation</groupId>
            <artifactId>validation-api</artifactId>
            <version>1.1.0.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-validator</artifactId>
            <version>5.2.4.Final</version>
        </dependency>
        <dependency>
            <groupId>javax.el</groupId>
            <artifactId>javax.el-api</artifactId>
            <version>2.2.4</version>
        </dependency>
    </dependencies>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>
</project>

pom.xml 对于网络项目：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.ucll</groupId>
    <artifactId>LoLWithBuddies-web</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>war</packaging>

    <name>LoLWithBuddies-web</name>

    <properties>
        <endorsed.dir>${project.build.directory}/endorsed</endorsed.dir>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>3.1.0</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>nz.net.ultraq.thymeleaf</groupId>
            <artifactId>thymeleaf-layout-dialect</artifactId>
            <version>1.3.3</version>
        </dependency>
        <dependency>
            <groupId>org.thymeleaf</groupId>
            <artifactId>thymeleaf</artifactId>
            <version>2.1.4.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.thymeleaf</groupId>
            <artifactId>thymeleaf-spring4</artifactId>
            <version>2.1.4.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>com.ucll</groupId>
            <artifactId>LoLWithBuddies</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aop</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aspects</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context-support</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-expression</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-framework-bom</artifactId>
            <version>4.0.1.RELEASE</version>
            <type>pom</type>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-instrument</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-instrument-tomcat</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jms</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-messaging</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-orm</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-oxm</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-tx</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc-portlet</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-websocket</artifactId>
            <version>4.0.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet.jsp.jstl</groupId>
            <artifactId>javax.servlet.jsp.jstl-api</artifactId>
            <version>1.2.1</version>
        </dependency>
        <dependency>
            <groupId>org.glassfish.web</groupId>
            <artifactId>javax.servlet.jsp.jstl</artifactId>
            <version>1.2.2</version>
        </dependency>
        <dependency>
            <groupId>org.eclipse.persistence</groupId>
            <artifactId>eclipselink</artifactId>
            <version>2.5.2</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.eclipse.persistence</groupId>
            <artifactId>org.eclipse.persistence.jpa.modelgen.processor</artifactId>
            <version>2.5.2</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>javax</groupId>
            <artifactId>javaee-web-api</artifactId>
            <version>7.0</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>1.7</source>
                    <target>1.7</target>
                    <compilerArguments>
                        <endorseddirs>${endorsed.dir}</endorseddirs>
                    </compilerArguments>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <version>2.3</version>
                <configuration>
                    <failOnMissingWebXml>false</failOnMissingWebXml>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <version>2.6</version>
                <executions>
                    <execution>
                        <phase>validate</phase>
                        <goals>
                            <goal>copy</goal>
                        </goals>
                        <configuration>
                            <outputDirectory>${endorsed.dir}</outputDirectory>
                            <silent>true</silent>
                            <artifactItems>
                                <artifactItem>
                                    <groupId>javax</groupId>
                                    <artifactId>javaee-endorsed-api</artifactId>
                                    <version>7.0</version>
                                    <type>jar</type>
                                </artifactItem>
                            </artifactItems>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
    <repositories>
        <repository>
            <id>unknown-jars-temp-repo</id>
            <name>A temporary repository created by NetBeans for libraries and jars it could not identify. Please replace the dependencies in this repository with correct ones and delete this repository.</name>
            <url>file:${project.basedir}/lib</url>
        </repository>
    </repositories>
</project>

示例控制器，我在我的网络应用程序中从我的域项目自动装配我的服务。此服务持有 RelationalLeagueDB class:

LoLWithBuddies-web/src/main/java/com/ucll/LoLWithBuddies/controller/LeagueController.java

package com.ucll.lolwithbuddies.controller;

import com.ucll.lolwithbuddies.domain.League;
import com.ucll.lolwithbuddies.service.Service;
import com.ucll.lolwithbuddies.service.ServiceException;
import java.util.List;
import javax.validation.Valid;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;

/**
 *
 * @author Christophe
 */
@Controller
@RequestMapping(value="/league")
public class LeagueController {

    @Autowired
    private Service service; 
    private boolean update=false;

    @RequestMapping(method=RequestMethod.GET)
    public ModelAndView getLeagues() throws ServiceException {

        List<League> leagues = service.getAllLeagues();
        return new ModelAndView("leagues", "leagues", leagues);
    }

    @RequestMapping(value="/new", method=RequestMethod.GET)
    public ModelAndView getNewForm() {
        update=false;
        League newLeague = new League();
        return new ModelAndView("leagueform", "leagueForm", newLeague);
    }

    @RequestMapping(method=RequestMethod.POST)
    public String save(@Valid @ModelAttribute("leagueForm") League leagueForm, BindingResult result) throws ServiceException {

        if (result.hasErrors()) {
            return "leagueform";
        }

        if(update) {
            service.updateLeague(leagueForm);
        } else {
            service.addLeague(leagueForm);
        }
        update=false;
        return "redirect:/league";
    }


    @RequestMapping(value="/{id}", method=RequestMethod.GET)
    public ModelAndView getEditForm(@PathVariable long id) throws ServiceException {
        update=true;
        return new ModelAndView("leagueform", "leagueForm", service.getLeague(id));
    }

    @RequestMapping(value="/{id}/delete", method=RequestMethod.GET)
    public ModelAndView getDeleteConfirmation(@PathVariable long id) throws ServiceException {
        return new ModelAndView("leaguedeleteconfirm", "delete", service.getLeague(id));
    }

    @RequestMapping(value="/delete", method=RequestMethod.POST)
    public String delete(@ModelAttribute("delete") League toDelete) throws ServiceException {

        service.deleteLeague(toDelete.getId());

        return "redirect:/league";
    }
}

服务 bean 在基于 Java 的配置中这样配置：

@Bean(name = "service", destroyMethod = "closeConnection")
    public Service service() throws ServiceException {
        Service bean = new LeagueService("JPA");
        return bean;
    }

注意我可以将参数传递给此服务（JPA 或本地）。我想将 JPA 用于我的生产代码，但为了测试我可以传递本地参数以使用内存中的 Map 存储库，它工作正常。

谁能给我指出正确的方向？

Answer 1

好的，我找到问题了。正如我所说，当我第一次运行应用程序时，应用程序可以正常运行。但是，下次当我第一次尝试重新运行我的应用程序时，说因为我做了一些更改并且不得不重建，GlassFish，我的应用程序部署的服务器，不会重新部署我的应用程序，并且旧版本保留在服务器上，旧上下文，因此我的实体是 'old version of themself'。在某种程度上，我的服务 destroyMethod 似乎没有被调用。

当我强制取消部署我的应用程序，重新启动服务器，然后重新运行我的应用程序时，它会工作。但是，目前我必须手动执行此操作。现在正在研究 maven-glassfish-plugin 以自动执行此操作。

JPA：对象不是已知的实体类型。完全不知道如何使用模块化域（持久性）项目配置 Spring 网络应用程序

JPA: Object is not a known Entity type. Completely confused as to how to configure a Spring web app with a modular domain (persistence) project

java

spring

jpa

eclipselink

maven