小型 facelet 应用程序中的 javax.persistence.TransactionRequiredException
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javax.persistence.TransactionRequiredException in small facelet application
提问by Sergei
I'm trying to persist some values to a MySql database from a small facelet application but keep getting this error. I had this same application with a JPS page and a servlet and it worked fine with roughly the same logic, this is my first time trying to work with facelets so it might just be something silly but i'd appriciate the help.
我正在尝试将一些值从一个小型 facelet 应用程序保存到 MySql 数据库，但不断收到此错误。我有一个带有 JPS 页面和 servlet 的相同应用程序，它在大致相同的逻辑下运行良好，这是我第一次尝试使用 facelets，所以它可能只是一些愚蠢的事情，但我会感谢帮助。
Thanks
谢谢
error
错误
javax.faces.el.EvaluationException: javax.persistence.TransactionRequiredException
at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:102)
at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102)
at javax.faces.component.UICommand.broadcast(UICommand.java:315)
at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:794)
at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1259)
at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1550)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:161)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:331)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
at com.sun.enterprise.v3.services.impl.ContainerMapper$AdapterCallable.call(ContainerMapper.java:317)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:195)
at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:860)
at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:757)
at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1056)
at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:229)
at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
at java.lang.Thread.run(Thread.java:722)
Caused by: javax.persistence.TransactionRequiredException
at com.sun.enterprise.container.common.impl.EntityManagerWrapper.doTxRequiredCheck(EntityManagerWrapper.java:163)
at com.sun.enterprise.container.common.impl.EntityManagerWrapper.doTransactionScopedTxCheck(EntityManagerWrapper.java:145)
at com.sun.enterprise.container.common.impl.EntityManagerWrapper.persist(EntityManagerWrapper.java:263)
at vecka19.controller.BookController.addBook(BookController.java:28)
at vecka19.controller.BookController$Proxy$_$$_WeldClientProxy.addBook(BookController$Proxy$_$$_WeldClientProxy.java)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at javax.el.BeanELResolver.invokeMethod(BeanELResolver.java:779)
at javax.el.BeanELResolver.invoke(BeanELResolver.java:528)
at javax.el.CompositeELResolver.invoke(CompositeELResolver.java:257)
at com.sun.el.parser.AstValue.invoke(AstValue.java:248)
at com.sun.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:302)
at org.jboss.weld.util.el.ForwardingMethodExpression.invoke(ForwardingMethodExpression.java:39)
at org.jboss.weld.el.WeldMethodExpression.invoke(WeldMethodExpression.java:50)
at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:105)
at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:88)
... 32 more
index.xhtml
索引.xhtml
<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:c="http://java.sun.com/jsp/jstl/core">
<h:head>
<title>Vecka19</title>
</h:head>
<h:body>
<section id="bookForm">
<div>
<h:form id="bookForm">
<table>
<tr>
<td><h:outputLabel value="ID: " for="id"/></td>
<td><h:inputText id="id" value="#{book.bookId}"/></td>
</tr>
<tr>
<td><h:outputLabel value="TITLE: " for="title"/></td>
<td><h:inputText id="title" value="#{book.title}"/></td>
</tr>
<tr>
<td><h:outputLabel value="AUTHOR: " for="author"/></td>
<td><h:inputText id="author" value="#{book.author}"/></td>
</tr>
<tr>
<td><h:outputLabel value="PRICE: " for="price"/></td>
<td><h:inputText id="price" value="#{book.price}"/></td>
</tr>
<tr>
<td>
<h:commandButton value="Add" action="#{bookController.addBook()}" />
<h:commandButton value="Get" action="#{bookController.book}" />
<h:commandButton value="Edit" action="#{bookController.editBook()}" />
<h:commandButton value="Delete" action="#{bookController.deleteBook()}" />
</td>
</tr>
</table>
</h:form>
</div>
</section>
<br />
<section id="dbTable">
<div>
<table>
<th>ID</th>
<th>TITLE</th>
<th>AUTHOR</th>
<th>PRICE</th>
<c:forEach items="${bookController.books}" var="book">
<tr>
<td>${book.bookId}</td>
<td>${book.title}</td>
<td>${book.author}</td>
<td>${book.price}</td>
</tr>
</c:forEach>
</table>
</div>
</section>
</h:body>
BookController.java
图书控制器.java
package vecka19.controller;
import java.util.List;
import javax.enterprise.context.RequestScoped;
import javax.inject.Inject;
import javax.inject.Named;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import vecka19.model.Book;
@Named
@RequestScoped
public class BookController {
@Inject Book book;
@PersistenceContext
private EntityManager em;
public List getBooks() {
return em.createNamedQuery("Book.findAll").getResultList();
}
public Book getBook() {
return em.find(Book.class, book.getBookId());
}
public void addBook() {
em.persist(book);
}
public void editBook() {
em.merge(book);
}
public void deleteBook() {
em.remove(getBook());
}
}
Book.java
书.java
package vecka19.model;
import java.io.Serializable;
import javax.enterprise.context.RequestScoped;
import javax.inject.Named;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.Table;
import javax.validation.constraints.NotNull;
@Entity
@Named
@RequestScoped
@Table(name = "BOOKS")
@NamedQueries({@NamedQuery(name = "Book.findAll", query = "SELECT b FROM Book b")})
public class Book implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@NotNull
@Column(name = "BOOK_ID")
private Integer bookId;
@Column(name = "TITLE")
private String title;
@Column(name = "AUTHOR")
private String author;
@Column(name = "PRICE")
private Integer price;
public Book() {
}
public Book(Integer bookId) {
this.bookId = bookId;
}
public Integer getBookId() {
return bookId;
}
public void setBookId(Integer bookId) {
this.bookId = bookId;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
public Integer getPrice() {
return price;
}
public void setPrice(Integer price) {
this.price = price;
}
}
percistence.xml
感知.xml
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
<persistence-unit name="vecka19PU" transaction-type="JTA">
<jta-data-source>jdbc/MySQLDataSource</jta-data-source>
<exclude-unlisted-classes>false</exclude-unlisted-classes>
<properties/>
</persistence-unit>
</persistence>
采纳答案by BalusC
You're abusing a CDI managed bean as a business service. It has no clues of transaction management. You'd need to manually manage transactions. As this is usually a pain and you're apparently using Glassfish, which is a fullworthy Java EE container supporting EJBs, you'd rather like to use a fullworthy EJB for this. When using EntityManagerinside an EJB, the container will fully transparently manage DB transactions. One EJB method call counts as a single transaction (i.e. when you fire multiple DB queries and one of them fails, then everything will be automatically rolled back).
您正在滥用 CDI 托管 bean 作为业务服务。它没有事务管理的线索。您需要手动管理事务。由于这通常很痛苦，而且您显然在使用 Glassfish，它是一个支持 EJB 的完整 Java EE 容器，因此您更愿意为此使用完整的 EJB。在EntityManagerEJB 内部使用时，容器将完全透明地管理 DB 事务。一个 EJB 方法调用算作单个事务（即，当您触发多个数据库查询并且其中一个失败时，所有内容都将自动回滚）。
Overall, you seem to be mixing the responsibilities of the model, controller and service. Do not make your entity a managed bean as well. You should further absolutely also not perform business logic in a Javabean getter method (e.g. getBooks()). When referenced in an iterating component, it's invoked during every iteration round. So imagine that you've 100 records, then the DB will be hit 100 times. This is plain inefficient.
总的来说，您似乎混合了模型、控制器和服务的职责。不要让您的实体也成为托管 bean。您也绝对不要在 Javabean getter 方法（例如getBooks()）中执行业务逻辑。当在迭代组件中被引用时，它会在每个迭代轮中被调用。因此，假设您有 100 条记录，那么 DB 将被命中 100 次。这显然是低效的。
Here's how it should all look like:
下面是它的样子：
Model (the entity):
模型（实体）：
@Entity
@Table(name = "BOOKS")
public class Book implements Serializable {
// ...
}
Controller (the backing bean):
控制器（支持 bean）：
@Named
@RequestScoped
public class BookController {
private Book book;
private List<Book> books;
@EJB
private BookService service;
@PostConstruct
public void init() {
book = new Book();
books = service.list();
}
public void add() {
service.save(book);
init();
}
public Book getBook() {
return book;
}
public List<Book> getBooks() {
return books;
}
}
Service (the EJB):
服务（EJB）：
@Stateless
public class BookService {
@PersistenceContext
private EntityManager em;
public List<Book> list() {
return em.createQuery("FROM Book", Book.class).getResultList();
}
public Book find(Integer id) {
return em.find(Book.class, id);
}
public Integer save(Book book) {
em.persist(book);
return book.getId();
}
public void update(Book book) {
em.merge(book);
}
public void delete(Book book) {
em.remove(em.contains(book) ? book : em.merge(book));
}
}
View (the Facelet; simplified):
视图（Facelet；简化）：
<h:inputText id="title" value="#{bookController.book.title}"/>
<h:inputText id="author" value="#{bookController.book.author}"/>
<h:inputText id="price" value="#{bookController.book.price}"/>
<h:commandButton value="Add" action="#{bookController.add}" />
...
<h:dataTable value="#{bookController.books}" var="book">
<h:column><f:facet name="header">ID</f:facet>#{book.id}</h:column>
<h:column><f:facet name="header">Title</f:facet>#{book.title}</h:column>
<h:column><f:facet name="header">Author</f:facet>#{book.author}</h:column>
<h:column><f:facet name="header">Price</f:facet>#{book.price}</h:column>
</h:dataTable>
(your edit and delete buttons didn't make any sense, so I removed them, you might want to put them inside the data table)
（你的编辑和删除按钮没有任何意义，所以我删除了它们，你可能想把它们放在数据表中）
See also:
也可以看看：
回答by Sotirios Delimanolis
The javadoc for EntityManager#persist(Object)says
javadoc forEntityManager#persist(Object)说
Throws:TransactionRequiredException - if invoked on a container-managed entity manager of type PersistenceContextType.TRANSACTION and there is no transaction
抛出：TransactionRequiredException - 如果在 PersistenceContextType.TRANSACTION 类型的容器管理的实体管理器上调用并且没有事务
You need to call EntityManager.html#getTransaction()and begin a transactionbefore you call persist (and some of the other methods). Don't forget to also commitor rollbackthe transaction when you are done.
在调用persist（以及其他一些方法）之前，您需要调用EntityManager.html#getTransaction()并开始一个事务。完成后不要忘记也commit或rollback交易。
回答by Alexander Volkov
Just add @Transactionalannotation on your method, e.g.
只需@Transactional在您的方法上添加注释，例如
@Transactional // <-------------
public long setSessionState(StateEnum state, String hash) {
QSession s = QSession.session;
JPAUpdateClause upd = new JPAUpdateClause(em, s);
upd.set(s.state, state).where(s.hash.eq(hash));
return upd.execute();
}
