DeletePoll.java :  » Mobile » whiteboard309 » whiteboard » poll » Java Open Source

package whiteboard.poll;

import com.opensymphony.xwork2.ActionSupport;

import org.apache.struts2.util.ServletContextAware;

import whiteboard.HomePage;
import whiteboard.course.Course;

import java.sql.Connection;
import java.sql.PreparedStatement;

import javax.servlet.ServletContext;
import javax.sql.DataSource;

/**
 * Action to delete course from DB and homepage instance.
 * 
 * @author John
 * 
 */
public class DeletePoll extends ActionSupport implements ServletContextAware {

  private ServletContext servletContext;
  private String pollid; // the poll to be delete from db and object
  private HomePage homePage;

  
  public String execute() {
    homePage = getHomePage();
    Course currCourse = homePage.getSelectedCourse();
    String pollToBeDeleted = getPollid();

    /* only admins can delete */
    if (homePage.getAccountType().compareTo("administrator") == 0) {
      DataSource dbcp = (DataSource) servletContext
          .getAttribute("dbpool");

      boolean removedFromDB = removePollFromDB(pollToBeDeleted, dbcp);
      
      if (currCourse.removePoll(pollToBeDeleted) && removedFromDB) {
        return SUCCESS;
      }
    }
    validate();
    return INPUT;
  }

  /**
   * Delete the entry of the poll and its poll options with poll id pollid
   * from the database.
   * 
   * @param courseid
   * @param user
   */
  public static boolean removePollFromDB(String pollid, DataSource dbcp) {
    Connection con = null;
    boolean wasError = false;

    try {
      con = dbcp.getConnection();
      PreparedStatement prepStatement;

      // DELETE POLL
      String sql = "DELETE FROM polls WHERE pollid = ?";
      prepStatement = con.prepareStatement(sql);
      prepStatement.setInt(1, Integer.parseInt(pollid));
      prepStatement.executeUpdate();

      // DELETE POLL OPTIONS
      sql = "DELETE FROM polloptions WHERE pollid = ?";
      prepStatement = con.prepareStatement(sql);
      prepStatement.setInt(1, Integer.parseInt(pollid));
      prepStatement.executeUpdate();

      prepStatement.close();
    } catch (Exception ex) {
      ex.printStackTrace();
      wasError = true;
    } finally {
      if (con != null)
        try {
          con.close();
        } catch (Exception e) {
        }
    }

    return wasError;
  }

  private HomePage getHomePage() {
    return (HomePage) this.servletContext.getAttribute("homePage");
  }

  public void setServletContext(ServletContext arg0) {
    this.servletContext = arg0;
  }

  public void validate() {
    homePage = getHomePage();
    /* Can't perform this action */
    if (homePage == null)
      System.out.println("homepage is null");
    if (homePage.getAccountType().compareTo("administrator") != 0) {
      System.out.println("homepage <><><>");
      addFieldError(
          "pollid",
          getText("You cannot perform that because you are not admin."));
    }
  }

  public void setPollid(String pollid) {
    this.pollid = pollid;
  }

  public String getPollid() {
    return pollid;
  }
}