Question

我有一个使用Axis2创建的网络服务器。我的客户端是Android App。 webservice连接到数据库。但是webservice会自动停止。

连接数据库的代码`public class Connect { 公共连接连接（）{

    Connection conn = null;


    try {
        String userName = "Admin";
        String password = "admin";
        //String url = "jdbc:mysql://mysql.cs.nott.ac.uk:3306/svp01m";
        String url = "jdbc:mysql://localhost/tests";
        Class.forName("com.mysql.jdbc.Driver").newInstance();
        conn = DriverManager.getConnection(url, userName, password);

        System.out.println ("\n Database connection established");

    } catch (Exception e) {
         e.printStackTrace();
        System.err.println("\n Cannot connect to database server");
        System.exit(0);
    }

    return conn;
}

}`

从webservice调用的代码是

public class Calculate

{

public boolean populateLeagues(String username, String password){

    try {
        /*Create object of the Connect class*/
        Connect connect = new Connect();
        /* calling the Connection method of Connect class to establish a database connection*/
        Connection conn = connect.Connection();

        java.sql.PreparedStatement preparedStatement = null;
        /* Creating a query to be executed with prepared statement*/
        String query = "select name from users where name=?";

        preparedStatement = conn.prepareStatement(query);
        /*substitutes the value for ? in the prepared Statement */
        preparedStatement.setString(1, username);
        /* Result set to capture the results of the query*/
        ResultSet rs = preparedStatement.executeQuery();

        boolean empty = true;
        while (rs.next()) {
            empty=false;
            System.err.println("\n User Name exists  \n");
            return true;
        }

        if(empty)
        {
            System.out.println("\n the userame does not exists");
            return false;
        }
        rs.close();
        conn.close();

    } catch (Exception e) {
        //e.printStackTrace();
         System.err.println ("Cannot connect to database server");
         System.exit(0);
    }
    return true;

}

我得到的例外是

java.lang.ClassNotFoundException：com.mysql.jdbc.Driver 在org.apache.catalina.loader.WebappClassLoader.loadClass（WebappClassLoader.java:1680）在org.apache.catalina.loader.WebappClassLoader.loadClass（WebappClassLoader.java:1526） at java.lang.Class.forName0（Native Method） at java.lang.Class.forName（Unknown Source）在org.web.backend.calculate.Connect.Connection（Connect.java:17）在org.web.backend.calculate.Calculate.populateLeagues（Calculate.java:17） at sun.reflect.NativeMethodAccessorImpl.invoke0（Native Method） at sun.reflect.NativeMethodAccessorImpl.invoke（Unknown Source） at sun.reflect.DelegatingMethodAccessorImpl.invoke（Unknown Source） at java.lang.reflect.Method.invoke（Unknown Source）在org.apache.axis2.rpc.receivers.RPCUtil.invokeServiceClass（RPCUtil.java:194）在org.apache.axis2.rpc.receivers.RPCMessageReceiver.invokeBusinessLogic（RPCMessageReceiver.java:102） at org.apache.axis2.receivers.AbstractInOutMessageReceiver.invokeBusinessLogic（AbstractInOutMessageReceiver.java:40） at org.apache.axis2.receivers.AbstractMessageReceiver.receive（AbstractMessageReceiver.java:100）在org.apache.axis2.engine.AxisEngine.receive（AxisEngine.java:176） at org.apache.axis2.transport.http.HTTPTransportUtils.processHTTPPostRequest（HTTPTransportUtils.java:275）在org.apache.axis2.transport.http.AxisServlet.doPost（AxisServlet.java:133）在javax.servlet.http.HttpServlet.service（HttpServlet.java:637）在javax.servlet.http.HttpServlet.service（HttpServlet.java:717）在org.apache.catalina.core.ApplicationFilterChain.internalDoFilter（ApplicationFilterChain.java:290）在org.apache.catalina.core.ApplicationFilterChain.doFilter（ApplicationFilterChain.java:206）在org.apache.catalina.core.StandardWrapperValve.invoke（StandardWrapperValve.java:233） at org.apache.catalina.core.StandardContextValve.invoke（StandardContextValve.java:191）在org.apache.catalina.core.StandardHostValve.invoke（StandardHostValve.java:127） at org.apache.catalina.valves.ErrorReportValve.invoke（ErrorReportValve.java:102）在org.apache.catalina.core.StandardEngineValve.invoke（StandardEngineValve.java:109）在org.apache.catalina.connector.CoyoteAdapter.service（CoyoteAdapter.java:293）在org.apache.coyote.http11.Http11Processor.process（Http11Processor.java:859）在org.apache.coyote.http11.Http11Protocol $ Http11ConnectionHandler.process（Http11Protocol.java:602）在org.apache.tomcat.util.net.JIoEndpoint $ Worker.run（JIoEndpoint.java:489）在java.lang.Thread.run（未知来源）

无法连接到数据库服务器

当我尝试连接数据库时，Axis2 Web服务停止

0 个答案: