Question

我已经阅读并尝试过针对此JNDI上下文命名问题的30个Google和StackExchange结果，这让我感到疯狂。

我试图从Wrox的一本书中获取一些源代码，这本书只使用JNDI数据源显示Hibernate实体。

我收到以下错误：

javax.persistence.PersistenceException: Unable to build entity manager factory
    org.hibernate.jpa.HibernatePersistenceProvider.createEntityManagerFactory(HibernatePersistenceProvider.java:83)
    org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:54)
    javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:55)
    javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:39)
    com.wrox.site.EntityServlet.doGet(EntityServlet.java:82)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:618)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    org.apache.logging.log4j.core.web.Log4jServletFilter.doFilter(Log4jServletFilter.java:66)

root cause

org.hibernate.engine.jndi.JndiException: Unable to lookup JNDI name [java:comp/env/jdbc/EntityMappings]
    org.hibernate.engine.jndi.internal.JndiServiceImpl.locate(JndiServiceImpl.java:117)
    org.hibernate.engine.jdbc.connections.internal.DatasourceConnectionProviderImpl.configure(DatasourceConnectionProviderImpl.java:115)
    org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:111)
    org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:234)
    org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:206)
    org.hibernate.engine.jdbc.internal.JdbcServicesImpl.buildJdbcConnectionAccess(JdbcServicesImpl.java:260)
    org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:94)
    org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:111)
    org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:234)
    org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:206)
    org.hibernate.cfg.Configuration.buildTypeRegistrations(Configuration.java:1885)
    org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1843)
    org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:850)
    org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:843)
    org.hibernate.boot.registry.classloading.internal.ClassLoaderServiceImpl.withTccl(ClassLoaderServiceImpl.java:397)
    org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:842)
    org.hibernate.jpa.HibernatePersistenceProvider.createEntityManagerFactory(HibernatePersistenceProvider.java:75)
    org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:54)
    javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:55)
    javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:39)
    com.wrox.site.EntityServlet.doGet(EntityServlet.java:82)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:618)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    org.apache.logging.log4j.core.web.Log4jServletFilter.doFilter(Log4jServletFilter.java:66)

root cause

javax.naming.NameNotFoundException: Name [java:comp/env/jdbc/EntityMappings] is not bound in this Context. Unable to find [java:comp].
    org.apache.naming.NamingContext.lookup(NamingContext.java:818)
    org.apache.naming.NamingContext.lookup(NamingContext.java:152)
    javax.naming.InitialContext.lookup(InitialContext.java:421)
    org.hibernate.engine.jndi.internal.JndiServiceImpl.locate(JndiServiceImpl.java:114)
    org.hibernate.engine.jdbc.connections.internal.DatasourceConnectionProviderImpl.configure(DatasourceConnectionProviderImpl.java:115)
    org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:111)
    org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:234)
    org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:206)
    org.hibernate.engine.jdbc.internal.JdbcServicesImpl.buildJdbcConnectionAccess(JdbcServicesImpl.java:260)
    org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:94)
    org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:111)
    org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:234)
    org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:206)
    org.hibernate.cfg.Configuration.buildTypeRegistrations(Configuration.java:1885)
    org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1843)
    org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:850)
    org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:843)
    org.hibernate.boot.registry.classloading.internal.ClassLoaderServiceImpl.withTccl(ClassLoaderServiceImpl.java:397)
    org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:842)
    org.hibernate.jpa.HibernatePersistenceProvider.createEntityManagerFactory(HibernatePersistenceProvider.java:75)
    org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:54)
    javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:55)
    javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:39)
    com.wrox.site.EntityServlet.doGet(EntityServlet.java:82)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:618)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    org.apache.logging.log4j.core.web.Log4jServletFilter.doFilter(Log4jServletFilter.java:66)

所以我试图在EntityServlet.java中注释出构建EntityManager的行：

Context ctx = new InitialContext();
    DataSource ds = (DataSource)ctx.lookup("java:comp/env/jdbc/EntityMappings");

Connection c = null;

c = ds.getConnection();

并且它根本不抱怨。

知道到底发生了什么事吗？

这是带有Tomcat 8的Java 8。

幅/ WEB-INF：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
                             http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">

    <display-name>Entity Mappings Application</display-name>

    <jsp-config>
        <jsp-property-group>
            <url-pattern>*.jsp</url-pattern>
            <url-pattern>*.jspf</url-pattern>
            <page-encoding>UTF-8</page-encoding>
            <scripting-invalid>true</scripting-invalid>
            <include-prelude>/WEB-INF/jsp/base.jspf</include-prelude>
            <trim-directive-whitespaces>true</trim-directive-whitespaces>
            <default-content-type>text/html</default-content-type>
        </jsp-property-group>
    </jsp-config>

    <session-config>
        <session-timeout>30</session-timeout>
        <cookie-config>
            <http-only>true</http-only>
        </cookie-config>
        <tracking-mode>COOKIE</tracking-mode>
    </session-config>

    <distributable />

    <resource-ref>
        <description>DB Connection</description>
        <res-ref-name>jdbc/EntityMappings</res-ref-name>
        <res-type>javax.sql.DataSource</res-type>
        <res-auth>Container</res-auth>
    </resource-ref>

</web-app>

幅/ META-INF / context.xml中：

<Context>

 <Resource name="jdbc/EntityMappings" type="javax.sql.DataSource"
               maxActive="50" maxIdle="5" maxWait="10000"
               username="***" password="***" driverClassName="com.mysql.jdbc.Driver"
               url="jdbc:mysql://localhost:3306/EntityMappings"/>

</Context>

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.wrox</groupId>
    <artifactId>entity-mappings</artifactId>
    <version>1.0.0-SNAPSHOT</version>
    <packaging>war</packaging>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <log4j.version>2.0-rc1</log4j.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>3.1.0</version>
            <scope>provided</scope>
        </dependency>

        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>javax.servlet.jsp-api</artifactId>
            <version>2.3.1</version>
            <scope>provided</scope>
        </dependency>

        <dependency>
            <groupId>javax.el</groupId>
            <artifactId>javax.el-api</artifactId>
            <version>3.0.0</version>
            <scope>provided</scope>
        </dependency>

        <dependency>
            <groupId>javax.servlet.jsp.jstl</groupId>
            <artifactId>javax.servlet.jsp.jstl-api</artifactId>
            <version>1.2.1</version>
            <scope>compile</scope>
        </dependency>

        <dependency>
            <groupId>org.glassfish.web</groupId>
            <artifactId>javax.servlet.jsp.jstl</artifactId>
            <version>1.2.2</version>
            <scope>compile</scope>
            <exclusions>
                <exclusion>
                    <groupId>javax.servlet</groupId>
                    <artifactId>servlet-api</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>javax.servlet.jsp</groupId>
                    <artifactId>jsp-api</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>javax.servlet.jsp.jstl</groupId>
                    <artifactId>jstl-api</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

        <dependency>
            <groupId>javax.websocket</groupId>
            <artifactId>javax.websocket-api</artifactId>
            <version>1.0</version>
            <scope>provided</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
            <version>3.1</version>
            <scope>compile</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-api</artifactId>
            <version>${log4j.version}</version>
            <scope>compile</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>
            <version>${log4j.version}</version>
            <scope>runtime</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-jcl</artifactId>
            <version>${log4j.version}</version>
            <scope>runtime</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-slf4j-impl</artifactId>
            <version>${log4j.version}</version>
            <scope>runtime</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-taglib</artifactId>
            <version>${log4j.version}</version>
            <scope>runtime</scope>
        </dependency>

        <dependency>
            <groupId>javax.inject</groupId>
            <artifactId>javax.inject</artifactId>
            <version>1</version>
            <scope>compile</scope>
        </dependency>

        <dependency>
            <groupId>javax.annotation</groupId>
            <artifactId>javax.annotation-api</artifactId>
            <version>1.2</version>
            <scope>runtime</scope>
        </dependency>

        <dependency>
            <groupId>org.jboss.logging</groupId>
            <artifactId>jboss-logging</artifactId>
            <version>3.2.0.Beta1</version>
            <scope>runtime</scope>
        </dependency>

<dependency>
    <groupId>org.hibernate.javax.persistence</groupId>
    <artifactId>hibernate-jpa-2.1-api</artifactId>
    <version>1.0.0.Final</version>
</dependency>



        <dependency>
            <groupId>javax.transaction</groupId>
            <artifactId>javax.transaction-api</artifactId>
            <version>1.2</version>
            <scope>compile</scope>
        </dependency>

        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-entitymanager</artifactId>
            <version>4.3.5.Final</version>
            <scope>runtime</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.jboss.spec.javax.transaction</groupId>
                    <artifactId>jboss-transaction-api_1.2_spec</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>xml-apis</groupId>
                    <artifactId>xml-apis</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.jboss.logging</groupId>
                    <artifactId>jboss-logging</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

    <build>
        <sourceDirectory>source/production/java</sourceDirectory>
        <resources>
            <resource>
                <directory>source/production/resources</directory>
            </resource>
        </resources>

        <testSourceDirectory>source/test/java</testSourceDirectory>
        <testResources>
            <testResource>
                <directory>source/test/resources</directory>
            </testResource>
        </testResources>

        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <version>2.3</version>
                <configuration>
                    <warSourceDirectory>web</warSourceDirectory>
                </configuration>
            </plugin>
            <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>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

Answer 1

stacktrace中的以下方法

org.hibernate.boot.registry.classloading.internal.ClassLoaderServiceImpl.withTccl（）

更改TCCL（Thread.currentThread（）。getContextClassLoader（））。

由于Tomcat中的JNDI由webapp的类加载器限定（因此不同的Web应用程序具有不同的JNDI树），这会破坏JNDI查找。

Answer 2

在您的web.xml中，请尝试<resource-env-ref>而不是<resource-ref>

    <resource-env-ref>
        <resource-env-ref-name>jdbc/EntityMappings</resource-env-ref-name>
        <resource-env-ref-type>javax.sql.DataSource</resource-env-ref-type>
    </resource-env-ref>

找不到JNDI上下文

2 个答案: