我是JavaEE的新人，现在正在阅读＆＃34; Goncalves A.开始Java EE 7 ＆＃34;书。我在为实体编写单元测试时遇到了问题。 我使用的是NetBeans 8.2，Hibernate 4.3和PostgreSQL 10.2。
该项目由 New Project - ＆gt;创建。 Java Web - ＆gt;使用JSF和Hibernate库的Web应用程序。
这是我的代码：
Book.java
@Entity
public class Book implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
@NotNull
private String title;
private Integer price;
public Book(String title, Integer price) {
this.title = title;
this.price = price;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public Integer getPrice() {
return price;
}
public void setPrice(Integer price) {
this.price = price;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
@Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
@Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof Book)) {
return false;
}
Book other = (Book) object;
if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
@Override
public String toString() {
return "epic.Book[ id=" + id + " ]";
}
}
BookTest.java
public class BookTest {
private static EntityManagerFactory emf = Persistence.createEntityManagerFactory("EpicWebAppTestPU");
private EntityManager em;
private EntityTransaction tx;
@Before
public void initEntityManager() throws Exception {
em = emf.createEntityManager();
tx = em.getTransaction();
}
@After
public void closeEntityManager() throws Exception {
if (em != null) {
em.close();
}
}
@Test
public void shouldCreateBook() throws Exception {
Book book = new Book("EpicBook", 9999);
tx.begin();
em.persist(book);
tx.commit();
Assert.assertNotNull( book.getId());
}
}
\ SRC \ CONF \ persistence.xml中
<?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="EpicWebAppPU" transaction-type="JTA">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<class>com.epic.Book</class>
<properties>
<property name="javax.persistence.schema-generation-action" value="drop-and-create"/>
<property name="javax.persistence.schema-generation-target" value="database"/>
<property name="javax.persistence.jdbc.driver" value="org.postgresql.Driver"/>
<property name="javax.persistence.jdbc.url" value="jdbc:postgresql://localhost:5432/cosuket;create=true"/>
<property name="javax.persistence.jdbc.user" value="root"/>
<property name="javax.persistence.jdbc.password" value="toor"/>
</properties>
</persistence-unit>
<persistence-unit name="EpicWebAppTestPU" transaction-type="JTA">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<class>com.epic.Book</class>
<properties>
<property name="javax.persistence.schema-generation-action" value="drop-and-create"/>
<property name="javax.persistence.schema-generation-target" value="database"/>
<property name="javax.persistence.jdbc.driver" value="org.postgresql.Driver"/>
<property name="javax.persistence.jdbc.url" value="jdbc:postgresql://localhost:5432/cosuketTest;create=true"/>
<property name="javax.persistence.jdbc.user" value="root"/>
<property name="javax.persistence.jdbc.password" value="toor"/>
</properties>
</persistence-unit>
</persistence>
但是测试失败并显示消息：
Null测试：导致ERROR null java.lang.ExceptionInInitializerError at java.lang.Class.forName0（Native Method）at java.lang.Class.forName（Class.java:264）引起： javax.persistence.PersistenceException：没有持久性提供程序 EntityManager名为EpicWebAppTestPU atjavax.persistence.Persistence.createEntityManagerFactory（Persistence.java:61） 在 javax.persistence.Persistence.createEntityManagerFactory（Persistence.java:39） 在epic.BookTest。（BookTest.java:20）
我已尝试使用<provider>org.hibernate.ejb.HibernatePersistence</provider>和<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>，但结果相同：找不到EpicWebAppTestPU。我做错了什么？
更新。我用maven重新创建了项目。
的pom.xml
<?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.epic</groupId>
<artifactId>EpicWebMaven</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>war</packaging>
<name>EpicWebMaven</name>
<properties>
<endorsed.dir>${project.build.directory}/endorsed</endorsed.dir>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>4.3.1.Final</version>
</dependency>
<dependency>
<groupId>unknown.binary</groupId>
<artifactId>hibernate-jpamodelgen-4.3.1.Final</artifactId>
<version>SNAPSHOT</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.hamcrest</groupId>
<artifactId>hamcrest-core</artifactId>
<version>1.3</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>javax</groupId>
<artifactId>javaee-web-api</artifactId>
<version>7.0</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.postgresql</groupId>
<artifactId>postgresql</artifactId>
<version>42.2.2.jre7</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.7</source>
<target>1.7</target>
<compilerArguments>
<endorseddirs>${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>
现在我在构建项目时遇到了另一个错误。 BookTest.java:29为em = emf.createEntityManager();
java.lang.NullPointerException
at org.hibernate.engine.transaction.internal.jta.JtaStatusHelper.getStatus(JtaStatusHelper.java:76)
at org.hibernate.engine.transaction.internal.jta.JtaStatusHelper.isActive(JtaStatusHelper.java:118)
at org.hibernate.engine.transaction.internal.jta.CMTTransaction.join(CMTTransaction.java:149)
at org.hibernate.jpa.spi.AbstractEntityManagerImpl.joinTransaction(AbstractEntityManagerImpl.java:1602)
at org.hibernate.jpa.spi.AbstractEntityManagerImpl.postInit(AbstractEntityManagerImpl.java:210)
at org.hibernate.jpa.internal.EntityManagerImpl.<init>(EntityManagerImpl.java:91)
at org.hibernate.jpa.internal.EntityManagerFactoryImpl.internalCreateEntityManager(EntityManagerFactoryImpl.java:345)
at org.hibernate.jpa.internal.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:313)
at moe.dk_x86.epicwebmaven.BookTest.initEntityManager(BookTest.java:29)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:24)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.apache.maven.surefire.junit4.JUnit4TestSet.execute(JUnit4TestSet.java:53)
at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:123)
at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:104)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.maven.surefire.util.ReflectionUtils.invokeMethodWithArray(ReflectionUtils.java:164)
at org.apache.maven.surefire.booter.ProviderFactory$ProviderProxy.invoke(ProviderFactory.java:110)
at org.apache.maven.surefire.booter.SurefireStarter.invokeProvider(SurefireStarter.java:175)
at org.apache.maven.surefire.booter.SurefireStarter.runSuitesInProcessWhenForked(SurefireStarter.java:107)
at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:68)
答案 0 :(得分：1)
＆LT;提供商GT; org.hibernate.ejb.HibernatePersistence＆LT; /提供商GT;应该有用。
尝试使用以下提供商：
＆LT;提供商GT; org.hibernate.jpa.HibernatePersistenceProvider＆LT; /提供商GT;
如果仍然无法正常工作，那么可能会丢失一个罐子。
检查是否存在hibernate-entitymanager jar。