java - 具有纯 JDBC-JNDI :javax. naming.NameNotFoundException : Name [jdbc/KDB] is not bound in this Context. 无法找到 [jdbc] 的 Tomcat 8.5

Question

现状

你好，

我在配置纯 JDBC-JNDI 连接时遇到问题。我没有使用任何特殊框架*(没有 Spring，没有 Hibernate)。我在我的计算机 (localhost) 上运行 Tomcat 8.5.15。数据库位于我已验证连接正常工作的远程服务器中。我已将 JDBC 驱动程序 jar 文件放在 apache-tomcat-8.5.15/lib/driver_lib 中。

我遇到的错误是:

javax.naming.NameNotFoundException: Name [jdbc/KDB] is not bound in this Context. Unable to find [jdbc].

我不确定为什么会收到此消息；我尝试遵循 Tomcat 网站上提到的指南。我也关注了 StackOverflow 上关于此问题的大部分问题，但此消息仍然出现。请帮忙!

环境

• Tomcat 8.5.15
• Java jdk 1.8.0_102 上的 Eclispe JavaEE Neon.3
• 运行环境:Java jre 1.7.0_80 (Java8 好像和 Tomcat 有一些问题)
• 专家

文件

apache-tomcat-8.5.15/conf/server.xml

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

<Server port="8005" shutdown="SHUTDOWN">
  <Listener className="org.apache.catalina.startup.VersionLoggerListener" />
  <!-- Security listener. Documentation at /docs/config/listeners.html
  <Listener className="org.apache.catalina.security.SecurityListener" />
  -->
  <!--APR library loader. Documentation at /docs/apr.html -->
  <Listener className="org.apache.catalina.core.AprLifecycleListener" SSLEngine="on" />
  <!-- Prevent memory leaks due to use of particular java/javax APIs-->
  <Listener className="org.apache.catalina.core.JreMemoryLeakPreventionListener" />
  <Listener className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener" />
  <Listener className="org.apache.catalina.core.ThreadLocalLeakPreventionListener" />

  <!-- Global JNDI resources
       Documentation at /docs/jndi-resources-howto.html
  -->
  <GlobalNamingResources>
    <Resource name="UserDatabase" auth="Container"
              type="org.apache.catalina.UserDatabase"
              description="User database that can be updated and saved"
              factory="org.apache.catalina.users.MemoryUserDatabaseFactory"
              pathname="conf/tomcat-users.xml" />

    <!-- confidential -->
    <Resource name="jdbc/KDB" 
      global="jdbc/KDB" 
      auth="Container" 
      type="javax.sql.DataSource" 
      driverClassName="xxxx" 
      url="xxxx" 
      username="xxxx" 
      password="xxxx" 

      maxActive="100" 
      maxIdle="20" 
      minIdle="5" 
      maxWait="10000"/>
  </GlobalNamingResources>

  <Service name="Catalina">


    <Connector port="8080" protocol="HTTP/1.1"
               connectionTimeout="20000"
               redirectPort="8443" />

    <Connector port="8009" protocol="AJP/1.3" redirectPort="8443" />


    <Engine name="Catalina" defaultHost="localhost">

      <!-- Use the LockOutRealm to prevent attempts to guess user passwords
           via a brute-force attack -->
      <Realm className="org.apache.catalina.realm.LockOutRealm">
        <Realm className="org.apache.catalina.realm.UserDatabaseRealm"
               resourceName="UserDatabase"/>
      </Realm>

      <Host name="localhost"  appBase="webapps"
            unpackWARs="true" autoDeploy="true">

        <Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs"
               prefix="localhost_access_log" suffix=".txt"
               pattern="%h %l %u %t &quot;%r&quot; %s %b" />

      </Host>
    </Engine>
  </Service>
</Server>

[项目]/src/main/webapp/WEB-INF/web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://java.sun.com/xml/ns/javaee"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
    metadata-complete="false" version="3.0">
    <display-name>Servlet 3.0 Web Application</display-name>

    <!-- Application class name -->
    <context-param>
        <param-name>org.restlet.application</param-name>
        <param-value>kk.MainApplication</param-value>
    </context-param>

    <!-- Restlet adapter -->
    <servlet>
        <servlet-name>RestletServlet</servlet-name>
        <servlet-class>org.restlet.ext.servlet.ServerServlet</servlet-class>
    </servlet>

    <!-- Catch all requests -->
    <servlet-mapping>
        <servlet-name>RestletServlet</servlet-name>
        <url-pattern>/*</url-pattern>
    </servlet-mapping>

    <!-- JDNI Resource -->
    <resource-ref>
        <description>DB Connection</description>
        <res-ref-name>jdbc/KDB</res-ref-name>
        <res-type>javax.sql.DataSource</res-type>
        <res-auth>Container</res-auth>
    </resource-ref>

    <welcome-file-list>
        <welcome-file>/user</welcome-file>
    </welcome-file-list>
</web-app>

[项目]/src/main/webapp/META-INF/context.xml

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

<Context>

    <WatchedResource>WEB-INF/web.xml</WatchedResource>
    <WatchedResource>${catalina.base}/conf/web.xml</WatchedResource>

    <ResourceLink name="jdbc/KDB" global="jdbc/KDB"
        auth="Container" type="javax.sql.DataSource" />
</Context>

用于运行查询的代码(在 Database.java 中)

public List<T> runQuery(String query) throws SQLException {
        List<T> result = null;
        Connection con = null;
        Context ctx = null;
        Statement stmt = null;
        ResultSet rs = null;
        try {
            result = new ArrayList<T>();
            ctx = new InitialContext();
            DataSource ds = (DataSource) ctx.lookup("java:/comp/env/jdbc/KDB");

            con = ds.getConnection();
            stmt = con.createStatement();
            rs = stmt.executeQuery(query);

            rs.beforeFirst();
            while (!rs.next()) {
                T user = dtoClass.newInstance();
                for (Entry<String, String> entry : dtoFieldMap.entrySet()) {
                    String value = rs.getString(entry.getValue());
                    user.setField(entry.getKey(), value);
                }
                result.add(user);
            }
            log.trace("runQuery: query completed successfully");
            log.info("Driver Name: " + con.getMetaData().getDriverName());
        } catch (NamingException | SQLException | InstantiationException | IllegalAccessException ex) {
            log.error("An Exception occurred in runQuery(String)", ex);
        } catch (NoSuchFieldException | SecurityException | IllegalArgumentException ex) {
            log.error("Field-related Exception", ex);
            ex.printStackTrace();
        } finally {
            DbUtils.close(rs);
            DbUtils.close(stmt);
            DbUtils.close(con);
        }

        return result;
}

控制台输出

11:30:55.368 [http-nio-8090-exec-2] ERROR kk.db.Database - An Exception occurred in runQuery(String)
javax.naming.NameNotFoundException: Name [jdbc/KDB] is not bound in this Context. Unable to find [jdbc].
    at org.apache.naming.NamingContext.lookup(NamingContext.java:816) ~[catalina.jar:8.5.15]
    at org.apache.naming.NamingContext.lookup(NamingContext.java:173) ~[catalina.jar:8.5.15]
    at org.apache.naming.factory.ResourceLinkFactory.getObjectInstance(ResourceLinkFactory.java:152) ~[catalina.jar:8.5.15]
    at javax.naming.spi.NamingManager.getObjectInstance(NamingManager.java:321) ~[?:1.8.0_131]
    at org.apache.naming.NamingContext.lookup(NamingContext.java:839) ~[catalina.jar:8.5.15]
    at org.apache.naming.NamingContext.lookup(NamingContext.java:159) ~[catalina.jar:8.5.15]
    at org.apache.naming.NamingContext.lookup(NamingContext.java:827) ~[catalina.jar:8.5.15]
    at org.apache.naming.NamingContext.lookup(NamingContext.java:159) ~[catalina.jar:8.5.15]
    at org.apache.naming.NamingContext.lookup(NamingContext.java:827) ~[catalina.jar:8.5.15]
    at org.apache.naming.NamingContext.lookup(NamingContext.java:159) ~[catalina.jar:8.5.15]
    at org.apache.naming.NamingContext.lookup(NamingContext.java:827) ~[catalina.jar:8.5.15]
    at org.apache.naming.NamingContext.lookup(NamingContext.java:173) ~[catalina.jar:8.5.15]
    at org.apache.naming.SelectorContext.lookup(SelectorContext.java:163) ~[catalina.jar:8.5.15]
    at javax.naming.InitialContext.lookup(InitialContext.java:417) ~[?:1.8.0_131]
    at kk.db.Database.runQuery(Database.java:154) [classes/:?]
    at kk.UserResource.getQueryResult(UserResource.java:137) [classes/:?]
    at kk.UserResource.toHtml(UserResource.java:63) [classes/:?]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_131]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_131]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_131]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_131]
    at org.restlet.resource.ServerResource.doHandle(ServerResource.java:511) [org.restlet-2.3.10.jar:?]
    at org.restlet.resource.ServerResource.get(ServerResource.java:723) [org.restlet-2.3.10.jar:?]
    at org.restlet.resource.ServerResource.doHandle(ServerResource.java:603) [org.restlet-2.3.10.jar:?]
    at org.restlet.resource.ServerResource.doNegotiatedHandle(ServerResource.java:662) [org.restlet-2.3.10.jar:?]
    at org.restlet.resource.ServerResource.doConditionalHandle(ServerResource.java:348) [org.restlet-2.3.10.jar:?]
    at org.restlet.resource.ServerResource.handle(ServerResource.java:1020) [org.restlet-2.3.10.jar:?]
    at org.restlet.resource.Finder.handle(Finder.java:236) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.doHandle(Filter.java:150) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.handle(Filter.java:197) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Router.doHandle(Router.java:422) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Router.handle(Router.java:641) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.doHandle(Filter.java:150) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.handle(Filter.java:197) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.doHandle(Filter.java:150) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.handle(Filter.java:197) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.doHandle(Filter.java:150) [org.restlet-2.3.10.jar:?]
    at org.restlet.engine.application.StatusFilter.doHandle(StatusFilter.java:140) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.handle(Filter.java:197) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.doHandle(Filter.java:150) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.handle(Filter.java:197) [org.restlet-2.3.10.jar:?]
    at org.restlet.engine.CompositeHelper.handle(CompositeHelper.java:202) [org.restlet-2.3.10.jar:?]
    at org.restlet.engine.application.ApplicationHelper.handle(ApplicationHelper.java:77) [org.restlet-2.3.10.jar:?]
    at org.restlet.Application.handle(Application.java:385) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.doHandle(Filter.java:150) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.handle(Filter.java:197) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Router.doHandle(Router.java:422) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Router.handle(Router.java:641) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.doHandle(Filter.java:150) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.handle(Filter.java:197) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Router.doHandle(Router.java:422) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Router.handle(Router.java:641) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.doHandle(Filter.java:150) [org.restlet-2.3.10.jar:?]
    at org.restlet.routing.Filter.handle(Filter.java:197) [org.restlet-2.3.10.jar:?]
    at org.restlet.engine.CompositeHelper.handle(CompositeHelper.java:202) [org.restlet-2.3.10.jar:?]
    at org.restlet.Component.handle(Component.java:408) [org.restlet-2.3.10.jar:?]
    at org.restlet.Server.handle(Server.java:507) [org.restlet-2.3.10.jar:?]
    at org.restlet.engine.connector.ServerHelper.handle(ServerHelper.java:63) [org.restlet-2.3.10.jar:?]
    at org.restlet.engine.adapter.HttpServerHelper.handle(HttpServerHelper.java:143) [org.restlet-2.3.10.jar:?]
    at org.restlet.ext.servlet.ServerServlet.service(ServerServlet.java:1117) [org.restlet.ext.servlet-2.3.10.jar:?]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) [servlet-api.jar:?]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) [catalina.jar:8.5.15]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.15]
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) [tomcat-websocket.jar:8.5.15]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.15]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.15]
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) [catalina.jar:8.5.15]
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [catalina.jar:8.5.15]
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:478) [catalina.jar:8.5.15]
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [catalina.jar:8.5.15]
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:80) [catalina.jar:8.5.15]
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:624) [catalina.jar:8.5.15]
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [catalina.jar:8.5.15]
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) [catalina.jar:8.5.15]
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:799) [tomcat-coyote.jar:8.5.15]
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-coyote.jar:8.5.15]
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:861) [tomcat-coyote.jar:8.5.15]
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1455) [tomcat-coyote.jar:8.5.15]
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-coyote.jar:8.5.15]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [?:1.8.0_131]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [?:1.8.0_131]
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-util.jar:8.5.15]
    at java.lang.Thread.run(Thread.java:748) [?:1.8.0_131]

如有任何建议或解决方案，我们将不胜感激。谢谢。

*附言我也在使用 ReSTLet API、GSON、DbUtils 和 log4j2，但我认为这不会导致任何问题，因为它在代码中实现数据库之前不会。

Answer 1

你试过改变这条线

DataSource ds = (DataSource) ctx.lookup("java:/comp/env/jdbc/KDB");

为了这个？

DataSource ds = (DataSource) ctx.lookup("java:comp/env/jdbc/KDB");

(没有第一个斜杠)