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Tomcat cannot find JDBC driver when connecting to DB

I put the mysql driver in .../ROOT/WEB-INF/liband Tomcat 8.0/lib, but it has no effect. I use the following class to connect to the database:

package db;

import java.sql.*;

public class ConnectToDB implements AutoCloseable {
    Connection con;

    public ConnectToDB(String server, String database, String user,
            String password) throws SQLException {
        con = DriverManager.getConnection("jdbc:mysql://" + server + "/"
                + database, user, password);
    }

    @Override
    public void close() throws SQLException {
        con.close();
    }

    public Connection getConnection() {
        return con;
    }

}

The following classes are included in the Eclipse project:

1. SRC / nr3 / model

package nr3.model;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import db.ConnectToDB;
public class MusikkHandler {
    private ConnectToDB db;
    private Connection con;
    private String tableName;
    private PreparedStatement pstmtGetRows;

    public MusikkHandler(String server, String database, String user,
            String password) throws SQLException {
        db = new ConnectToDB(server, database, user, password);
        con = db.getConnection();
        tableName = "album";
    }

    public void close() throws SQLException {
        db.close();
    }

    public ArrayList<Album> getRows(String genre) throws SQLException {
        ArrayList<Album> list = new ArrayList<Album>();
        pstmtGetRows = con.prepareStatement("SELECT * FROM " + tableName
                + " WHERE SJANGER = ?");
        pstmtGetRows.setString(1, genre);
        ResultSet rs = pstmtGetRows.executeQuery();
        while (rs.next()) {
            list.add(new Album(rs.getString(1), rs.getString(2), rs.getInt(3),
                    rs.getInt(4), rs.getString(5)));
        }
        rs.close();
        pstmtGetRows.close();
        return list;
    }
}

-

package nr3.model;

public class Album {
    private String tittel;
    private String artist;
    private int spor;
    private int utgitt;
    private String sjanger;

    public Album (String artist, String tittel, int spor, int utgitt, String sjanger){
        setArtist(artist);
        setTittel(tittel);
        setUtgitt(utgitt);
        setSpor(spor);
        setSjanger(sjanger);
    }
    public Album(){
        this(null, null, 0, 0, null);
    }
    public void setTittel(String tittel){
        this.tittel = tittel;
    }
    public void setArtist(String artist){
        this.artist = artist;
    }
    public void setSpor(int spor) {
        this.spor = spor;
    }
    public void setUtgitt(int utgitt) {
        this.utgitt = utgitt;
    }
    public void setSjanger(String sjanger) {
        this.sjanger = sjanger;
    }
    public String getTittel() {
        return tittel;
    }
    public String getArtist() {
        return artist;
    }
    public int getSpor() {
        return spor;
    }
    public int getUtgitt() {
        return utgitt;
    }
    public String getSjanger() {
        return sjanger;
    }
    public String toString(){
        return getTittel() + " (" + getArtist() + ")" + " Utgitt: " 
                                               + getUtgitt(); 
    }
}

2. SRC / nr3 / servlets

package nr3.servlets;

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.SQLException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import nr3.model.Album;
import nr3.model.MusikkHandler;

public class MusikkValg extends HttpServlet {

    private static final long serialVersionUID = 428937262021570370L;

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        String genre = request.getParameter("sjanger");
        response.setCharacterEncoding("UTF-8");
        response.setContentType("text/html");
        PrintWriter out = response.getWriter();
        MusikkHandler mh;

        out.println("<html>");
        out.println("<head>");
        out.println("<title>Musikk</title>");
        out.println("</head>");
        out.println("<body>");
        out.println("<h1>MUSIKK-ANBEFALINGER</h1>");
        out.println("<br/>");
        out.println("<br/>");
        out.println("<h3>Da bør du kanskje forsøke en av disse:</h3>");
        out.println("<br/>");
        out.println("<br/>");
        try {
            mh = new MusikkHandler(" ", " ", " ", " ");
            for (Album a : mh.getRows(genre))
                out.println("<p>" + a + "</p>");
        } catch (SQLException e) {
            e.printStackTrace(out);
        }
        out.println("</body>");
        out.println("</html>");
    }

}

Update: I have the following stacktrace error in the browser:

java.sql.SQLException: jdbc: mysql://localhost/pg3100 at java.sql.DriverManager.getConnection( ) java.sql.DriverManager.getConnection( ) db.ConnectToDB. (ConnectToDB.java:10) nr3.model.MusikkHandler. (MusikkHandler.java:20) at nr3.servlets.MusikkValg.doGet(MusikkValg.java:39) at javax.servlet.http.HttpServlet.service(HttpServlet.java:618) : org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291) org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239) org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219) org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106) org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505) org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142) org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:610) org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:534) org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1081) org.apache.coyote.AbstractProtocol $AbstractConnectionHandler.process(AbstractProtocol.java:658) org.apache.coyote.http11.Http11AprProtocol $Http11ConnectionHandler.process(Http11AprProtocol.java:277) org.apache.tomcat.util.net.AprEndpoint $SocketProcessor.doRun(AprEndpoint.java:2381) org.apache.tomcat.util.net.AprEndpoint $SocketProcessor.run(AprEndpoint.java:2370) java.util.concurrent.ThreadPoolExecutor.runWorker( ) java.util.concurrent.ThreadPoolExecutor $Worker.run( ) org.apache.tomcat.util.threads.TaskThread $WrappingRunnable.run(TaskThread.java:61) java.lang.Thread.run( )

+4
1

, DriverManager . .

DriverManager.registerDriver (new com.mysql.jdbc.Driver());


Class.forName("com.mysql.jdbc.Driver");

getConnection(), , DriverManager.

: /webapps/ROOT/WEB-INF/lib - , , . , JDBC /webapps/<yourapp>/lib. Tomcat lib ( , , , , ..)

-: , - . , . .

+3

Source: https://habr.com/ru/post/1615509/

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