web.mvc.servlets.MyServlet.java Source code

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Here is the source code for web.mvc.servlets.MyServlet.java

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package web.mvc.servlets;

import java.io.IOException;
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.web.context.support.WebApplicationContextUtils;
import web.mvc.models.InfoItem;

/**
 *
 * @author CodeFire
 */
@WebServlet("/servlet-info")
public class MyServlet extends HttpServlet /* implements ApplicationContextAware */ {

    //    private ApplicationContext context;
    //
    //    @Override
    //    public void setApplicationContext(ApplicationContext context) throws BeansException {
    //        this.context = context;
    //    }

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        ApplicationContext context = WebApplicationContextUtils.getWebApplicationContext(getServletContext());

        if (context == null) {
            request.getRequestDispatcher("WEB-INF/jsp/db-info-error.jsp").forward(request, response);
        }

        DriverManagerDataSource dataSource = context.getBean(DriverManagerDataSource.class);
        List<InfoItem> data = new ArrayList<>();
        try {
            fillDataFromDataSource(data, dataSource);
        } catch (SQLException ex) {
            Logger.getLogger(MyServlet.class.getName()).log(Level.SEVERE, null, ex);
        }
        request.setAttribute("info", data);
        request.getRequestDispatcher("WEB-INF/jsp/db-info.jsp").forward(request, response);
    }

    private void fillDataFromDataSource(List<InfoItem> data, DriverManagerDataSource dataSource)
            throws SQLException {
        try (Connection connect = dataSource.getConnection()) {
            DatabaseMetaData metaData = connect.getMetaData();
            data.add(new InfoItem("database name", metaData.getDatabaseProductName()));
            data.add(new InfoItem("database version", metaData.getDatabaseProductVersion()));
            data.add(new InfoItem("driver name", metaData.getDriverName()));
            data.add(new InfoItem("driver version", metaData.getDriverVersion()));
        }
    }

}