Question

我是这个论坛的新手，也是JPA / EJB的新手。

我正在尝试将包含小应用程序的.war文件部署到tomcat服务器。该应用程序正在使用JTA与Derby数据库进行通信。

当我运行并从eclipse顶部运行在eclipse中运行的tomcat服务器时，一切都很完美，但是当我导出.war文件并尝试浏览应用程序时，它会抛出一个java.lang.ClassNotFoundException：javax。 persistence.PersistenceException。

我的持久性文件如下所示：

<?xml version="1.0" encoding="UTF-8"?>

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    version="1.0">

    <persistence-unit name="lab1" transaction-type="RESOURCE_LOCAL">
        <provider>org.apache.openjpa.persistence.PersistenceProviderImpl</provider>
        <!--<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>-->
        <class>entity.Team</class>
        <class>entity.Gambler</class>
        <class>entity.Bet</class>
        <class>entity.Game</class>
        <class>entity.Gameday</class>
          <properties>
       <property name="openjpa.ConnectionURL" value="jdbc:derby://localhost:1527/hean0901;create=true"/>
            <property name="openjpa.ConnectionDriverName" value="org.apache.derby.jdbc.ClientDriver"/>
            <property name="openjpa.ConnectionUserName"  value="lab1"/>
            <property name="openjpa.ConnectionPassword" value="user"/>
            <property name="lab1.log" value="DefaultLevel=TRACE"/>
            <property name="nonTransactionalDataSource" value="true"/> 
            <!-- <property name="openjpa.RuntimeUnenhancedClasses" value="supported"/>-->
            <property name="openjpa.jdbc.SynchronizeMappings" value="buildSchema" />
            <property name="eclipselink.logging.level" value="FINEST"/> 
        </properties>
    </persistence-unit>

</persistence>

并且抛出的错误如下所示：

org.apache.jasper.JasperException: An exception occurred processing JSP page /index.jsp at line 1

1: <jsp:forward page="Setupcheck.do" />


Stacktrace:
 org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:510)
 org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:401)
 org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
 org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
 javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
root cause

javax.servlet.ServletException: Servlet execution threw an exception
 org.apache.jasper.runtime.PageContextImpl.doForward(PageContextImpl.java:706)
 org.apache.jasper.runtime.PageContextImpl.forward(PageContextImpl.java:677)
 org.apache.jsp.index_jsp._jspService(index_jsp.java:54)
 org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
 javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
 org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
 org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
 org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
 javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
root cause

java.lang.NoClassDefFoundError: javax/persistence/PersistenceException
 model.Setupcheck.processRequest(Setupcheck.java:31)
 model.Setupcheck.doGet(Setupcheck.java:43)
 javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
 javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
 org.apache.jasper.runtime.PageContextImpl.doForward(PageContextImpl.java:706)
 org.apache.jasper.runtime.PageContextImpl.forward(PageContextImpl.java:677)
 org.apache.jsp.index_jsp._jspService(index_jsp.java:54)
 org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
 javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
 org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
 org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
 org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
 javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
root cause

java.lang.ClassNotFoundException: javax.persistence.PersistenceException
 org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1645)
 org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1491)
 model.Setupcheck.processRequest(Setupcheck.java:31)
 model.Setupcheck.doGet(Setupcheck.java:43)
 javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
 javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
 org.apache.jasper.runtime.PageContextImpl.doForward(PageContextImpl.java:706)
 org.apache.jasper.runtime.PageContextImpl.forward(PageContextImpl.java:677)
 org.apache.jsp.index_jsp._jspService(index_jsp.java:54)
 org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
 javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
 org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:377)
 org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
 org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
 javax.servlet.http.HttpServlet.service(HttpServlet.java:717)

有没有人遇到过这个？

祝你好运亨利克

Answer 1

您似乎缺少javax.persistence.PersistenceException类（JPA规范的一部分）。

可以在此处找到Java Persistence API JAR（包含PersistenceException类）：

http://repo1.maven.org/maven2/javax/persistence/persistence-api/1.0/persistence-api-1.0.jar

此JAR需要位于您的WEB-INF / lib文件夹中。

根据您设置Eclipse的方式，它可能会自动将这些JAR推送到Tomcat（通过定义库）。

但是，它尝试加载PersistenceException的事实很可能意味着一旦解决了这个ClassNotFoundException就会发生另一个异常（真正的异常）。

Answer 2

如果您使用Maven来管理项目依赖项，那么在pom.xml中为我提供以下内容：

<!-- https://mvnrepository.com/artifact/javax.persistence/persistence-api -->
<dependency>
    <groupId>javax.persistence</groupId>
    <artifactId>persistence-api</artifactId>
    <version>1.0.2</version>
</dependency>

部署到tomcat的war不能抛出java.lang.NoClassDefFoundError：javax / persistence / PersistenceException

2 个答案: