javax.naming.NameNotFoundException | JNDI查找

Question

我在這個網站上發現了很多關於解決問題的問題和解答，但找不到解決方案，因此我終於不得不再次發佈這個相同的問題！

我創建一個簡單的servlet DBCPDataSourceExample，並得到來自DataSource性質，而我在的Apache Tomcat V8應用服務器的server.xml & context.xml提供了一個連接。

以下爲DBCPDataSourceExample的servlet：

import javax.sql.DataSource; 
import javax.naming.Context; 
import javax.naming.InitialContext; 
import javax.naming.NamingException; 
import javax.servlet.http.HttpServlet; 
import javax.servlet.http.HttpServletRequest; 
import javax.servlet.http.HttpServletResponse; 

public class DBCPDataSourceExample extends HttpServlet { 

protected void doGet(HttpServletRequest request, HttpServletResponse respone) throws IOException { 
    Connection connection = null; 
    PreparedStatement statement = null; 
    ResultSet resultSet = null; 
    Context ctx ; 
    try { 
     try { 
      ctx = new InitialContext(); 
      Context ic= (Context) ctx.lookup("java:/comp/env"); 
      DataSource dts = (DataSource) ic.lookup("jdbc/harsh"); 
      connection = dts.getConnection(); 
     } catch (NamingException e) { 
      e.printStackTrace(); 
     } 
     statement = connection.prepareStatement("select * from stories"); 
     resultSet = statement.executeQuery(); 
     while (resultSet.next()) { 
      System.out.println("storyId: " + resultSet.getString("storyId")); 
      System.out.println("storyTitle: " + resultSet.getString("storyTitle")); 
     } 
    } catch (SQLException e) { 
     e.printStackTrace(); 
    } finally { 
     if (resultSet != null) try { resultSet.close(); } catch (SQLException e) {e.printStackTrace();} 
     if (statement != null) try { statement.close(); } catch (SQLException e) {e.printStackTrace();} 
     if (connection != null) try { connection.close(); } catch (SQLException e) {e.printStackTrace();} 
    } 

} 
} 

server.xmlResource映射：

<GlobalNamingResources> 
<!-- Editable user database that can also be used by 
    UserDatabaseRealm to authenticate users 
--> 
<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" /> 

<Resource name="jdbc/MyDB" 
      global="jdbc/MyDB" 
      auth="Container" 
      type="javax.sql.DataSource" 
      driverClassName="com.mysql.jdbc.Driver" 
      url="jdbc:mysql://localhost/storyBoard" 
      username="root" 
      password="" 

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

context.xmlResource映射：

<Resource name="jdbc/harsh" global="jdbc/MyDB" auth="container" type="javax.sql.DataSource" /> 

如果xml代碼有問題，我無法辨認。請幫忙！

下面是從控制檯堆棧跟蹤：

javax.naming.NameNotFoundException: Name [jdbc/harsh] is not bound in this Context. Unable to find [jdbc]. 
at org.apache.naming.NamingContext.lookup(NamingContext.java:818) 
at org.apache.naming.NamingContext.lookup(NamingContext.java:166) 
at com.dbcp.DBCPDataSourceExample.doGet(DBCPDataSourceExample.java:31) 
at javax.servlet.http.HttpServlet.service(HttpServlet.java:618) 
at javax.servlet.http.HttpServlet.service(HttpServlet.java:725) 
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291) 
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) 
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) 
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219) 
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106) 
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501) 
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142) 
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) 
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:610) 
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88) 
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:516) 
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1086) 
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:659) 
at org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:223) 
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1558) 
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1515) 
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) 
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) 
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) 
at java.lang.Thread.run(Unknown Source) 

的代碼行堆棧跟蹤點是這樣的：

   DataSource dts = (DataSource) ic.lookup("jdbc/harsh"); 

Answer 1

我們的平均時間，我們需要增加資源，在server.xml中創建一個資源鏈接，它是context.xml的必要位置。

在我們的例子中，我們保持的context.xml在我們的戰爭的META-INF和樣本項外觀

<ResourceLink name="email.host.name" global="email.host.name" type="java.lang.String"/>

請驗證您的context.xml條目。

還要確保你已經把mysql驅動放在tomcat的lib目錄中。

Answer 2

在你的Server.xml文件中，我認爲你需要在url中提供端口號。 例如url =「jdbc：mysql：// localhost：3306/storyBoard」