Question

我正在尝试使用以下代码为JNDI创建测试应用程序以及测试servlet，以验证连接是否已成功建立。我没有在 server.xml 和 context.xml 上进行任何配置设置，因为我在配置context.xml时不必这样做在应用程序的META-INF中

但是，我总是得到错误＆＃34; 无法创建类＆＃39;＆＃39;＆＃39;用于连接网址＆＃39; null ＆＃39; ＆＃34;

我搜索了旧问题，大多数类似错误消息的问题都是由错误的JDBC URL引起的。但就我而言，我并不认为这是JDBC URL的问题。
print stacktrace显示：

引起：java.sql.SQLException：没有合适的驱动程序 java.sql.DriverManager.getDriver（DriverManager.java:315）at org.apache.tomcat.dbcp.dbcp.BasicDataSource.createConnectionFactory（BasicDataSource.java:1437） ... 43更多

我甚至尝试在Tomcat的lib目录下使用MySQL jar文件;它仍然是一样的。完整堆栈跟踪如下：

信息：服务器启动时间为1116毫秒 org.apache.tomcat.dbcp.dbcp.SQLNestedException：无法创建JDBC 上课的司机＆＃39;＆＃39;用于连接网址＆＃39; null＆＃39;在 org.apache.tomcat.dbcp.dbcp.BasicDataSource.createConnectionFactory（BasicDataSource.java:1452）在 org.apache.tomcat.dbcp.dbcp.BasicDataSource.createDataSource（BasicDataSource.java:1371）在 org.apache.tomcat.dbcp.dbcp.BasicDataSource.getConnection（BasicDataSource.java:1044）在 org.angelfrend.samples.StandaloneJNDI.dao.TestServlet.doGet（TestServlet.java:45）在javax.servlet.http.HttpServlet.service（HttpServlet.java:624）at javax.servlet.http.HttpServlet.service（HttpServlet.java:731）at at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:303）在 org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:208）在 org.apache.tomcat.websocket.server.WsFilter.doFilter（WsFilter.java:52）在 org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:241）在 org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:208）在 org.apache.catalina.core.ApplicationDispatcher.invoke（ApplicationDispatcher.java:748）在 org.apache.catalina.core.ApplicationDispatcher.processRequest（ApplicationDispatcher.java:486）在 org.apache.catalina.core.ApplicationDispatcher.doForward（ApplicationDispatcher.java:411）在 org.apache.catalina.core.ApplicationDispatcher.forward（ApplicationDispatcher.java:338）在 org.apache.jasper.runtime.PageContextImpl.doForward（PageContextImpl.java:750）在 org.apache.jasper.runtime.PageContextImpl.forward（PageContextImpl.java:720）在org.apache.jsp.index_jsp._jspService（index_jsp.java:66）at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70）at javax.servlet.http.HttpServlet.service（HttpServlet.java:731）at at org.apache.jasper.servlet.JspServletWrapper.service（JspServletWrapper.java:439）在 org.apache.jasper.servlet.JspServlet.serviceJspFile（JspServlet.java:395）在org.apache.jasper.servlet.JspServlet.service（JspServlet.java:339）在javax.servlet.http.HttpServlet.service（HttpServlet.java:731）at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:303）在 org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:208）在 org.apache.tomcat.websocket.server.WsFilter.doFilter（WsFilter.java:52）在 org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:241）在 org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:208）在 org.apache.catalina.core.StandardWrapperValve.invoke（StandardWrapperValve.java:220）在 org.apache.catalina.core.StandardContextValve.invoke（StandardContextValve.java:122）在 org.apache.catalina.authenticator.AuthenticatorBase.invoke（AuthenticatorBase.java:505）在 org.apache.catalina.core.StandardHostValve.invoke（StandardHostValve.java:170）在 org.apache.catalina.valves.ErrorReportValve.invoke（ErrorReportValve.java:103）在 org.apache.catalina.valves.AccessLogValve.invoke（AccessLogValve.java:956）在 org.apache.catalina.core.StandardEngineValve.invoke（StandardEngineValve.java:116）在 org.apache.catalina.connector.CoyoteAdapter.service（CoyoteAdapter.java:423）在 org.apache.coyote.http11.AbstractHttp11Processor.process（AbstractHttp11Processor.java:1079）在 org.apache.coyote.AbstractProtocol $ AbstractConnectionHandler.process（AbstractProtocol.java:625）在 org.apache.tomcat.util.net.JIoEndpoint $ SocketProcessor.run（JIoEndpoint.java:316）在 java.util.concurrent.ThreadPoolExecutor.runWorker（ThreadPoolExecutor.java:1142）在 java.util.concurrent.ThreadPoolExecutor中的$ Worker.run（ThreadPoolExecutor.java:617）在 org.apache.tomcat.util.threads.TaskThread $ WrappingRunnable.run（TaskThread.java:61）在java.lang.Thread.run（Thread.java:745）引起： java.sql.SQLException：没有合适的驱动程序 java.sql.DriverManager.getDriver（DriverManager.java:315）at org.apache.tomcat.dbcp.dbcp.BasicDataSource.createConnectionFactory（BasicDataSource.java:1437） ... 43更多

的pom.xml

<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/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>org.samples.dao</groupId>
  <artifactId>StandaloneJNDI</artifactId>
  <packaging>war</packaging>
  <version>0.0.1-SNAPSHOT</version>
  <name>StandaloneJNDI Maven Webapp</name>
  <url>http://maven.apache.org</url>
  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.apache.commons</groupId>
        <artifactId>commons-dbcp2</artifactId>
        <version>2.1</version>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.36</version>
    </dependency>
    <dependency>
        <groupId>jstl</groupId>
        <artifactId>jstl</artifactId>
        <version>1.2</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-core</artifactId>
        <version>4.1.4.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>3.0.5.RELEASE</version>
    </dependency>
    <dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>servlet-api</artifactId>
    <version>2.4</version>
    <scope>provided</scope>
  </dependency>
  </dependencies>
  <build>
    <finalName>StandaloneJNDI</finalName>
  </build>

的web.xml

<web-app xmlns="http://java.sun.com/xml/ns/j2ee"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee 
      http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"
      version="2.4">
  <display-name>Servlet 2.4 Web Application</display-name>
  <description>MySQL Test</description>  
  <servlet>
    <servlet-name>TestServlet</servlet-name>    
    <servlet-class>org.samples.TestServlet</servlet-class>
  </servlet>   
  <servlet-mapping>
    <servlet-name>TestServlet</servlet-name>
    <url-pattern>/TestServlet</url-pattern>
  </servlet-mapping>  
  <resource-ref>
    <res-ref-name>jdbc/TestDB</res-ref-name>
    <res-type>javax.sql.DataSource</res-type>
    <res-auth>Container</res-auth>  
  </resource-ref>

context.xml（放在src / main / resources的META-INF文件夹中）

<Context>
        <Resource   name="jdbc/TestDB" 
        auth="Container" type="javax.sql.DataSource"
        maxActive="100" maxIdle="30" maxWait="10000"
        username="user" password="pass" 
        driverClassName="com.mysql.jdbc.Driver"
        url="jdbc:mysql://localhost:3306/JavaTest" /></Context>

有人可以帮助我了解它的工作原理吗？我们不能在不配置server.xml或context.xml的情况下创建JNDI连接吗？

使用应用程序

0 个答案: