Beispiel #1
0
  /** @return list of account of User's friends */
  public static ArrayList<Account> getFriendList(int accountId) {
    ConnectionPool pool = ConnectionPool.getInstance();
    Connection connection = pool.getConnection();
    PreparedStatement preStatement = null;
    try {
      String sqlCode =
          "SELECT acc.* "
              + "FROM Account as acc, Friend as fr "
              + "WHERE (fr.accountId1 = ? AND acc.accountId = fr.accountId2) OR "
              + "      (fr.accountId2 = ? AND acc.accountId = fr.accountId1)"
              + "ORDER BY username";
      preStatement = connection.prepareStatement(sqlCode);
      preStatement.setInt(1, accountId);
      preStatement.setInt(2, accountId);
      ResultSet resutSet = preStatement.executeQuery();

      ArrayList<Account> friendList = new ArrayList<Account>();
      while (resutSet.next()) {
        Account acc = new Account();
        acc.setBasicInfo(resutSet);
        friendList.add(acc);
      }
      return friendList;
    } catch (SQLException sqle) {
      sqle.printStackTrace();
      return null;
    } finally {
      freeDbResouce(preStatement, null, connection, pool);
    }
  }
Beispiel #2
0
  /**
   * add friend relation into table Friend
   *
   * @param accountId1 - account of first user
   * @param accountId2 - account of second user
   * @return true if success
   */
  public static boolean addFriends(int accountId1, int accountId2) {
    ConnectionPool pool = ConnectionPool.getInstance();
    Connection connection = pool.getConnection();
    PreparedStatement preStatement = null;
    try {
      String sqlCode = "INSERT INTO Friend VALUES " + "(?, ?)";
      preStatement = connection.prepareStatement(sqlCode);
      if (accountId1 < accountId2) {
        preStatement.setInt(1, accountId1);
        preStatement.setInt(2, accountId2);
      } else {
        preStatement.setInt(1, accountId2);
        preStatement.setInt(2, accountId1);
      }

      int nRows = preStatement.executeUpdate();
      if (nRows > 0) {
        return true;
      } else {
        return false;
      }
    } catch (SQLException sqle) {
      sqle.printStackTrace();
      return false;
    } finally {
      freeDbResouce(preStatement, null, connection, pool);
    }
  }
Beispiel #3
0
  /**
   * @param accountId1 - accountId of user 1
   * @param accountId2 - accountId of user 2
   * @return true if two account are friend
   */
  public static boolean areFriends(int accountId1, int accountId2) {
    ConnectionPool pool = ConnectionPool.getInstance();
    Connection connection = pool.getConnection();
    PreparedStatement preStatement = null;
    try {
      String sqlCode = "SELECT * FROM Friend " + "WHERE accountId1 = ? AND accountId2 = ?";

      preStatement = connection.prepareStatement(sqlCode);
      if (accountId1 < accountId2) {
        preStatement.setInt(1, accountId1);
        preStatement.setInt(2, accountId2);
      } else {
        preStatement.setInt(1, accountId2);
        preStatement.setInt(2, accountId1);
      }
      ResultSet resultSet = preStatement.executeQuery();
      if (resultSet.next()) {
        return true;
      } else {
        return false;
      }
    } catch (SQLException sqle) {
      sqle.printStackTrace();
      return false;
    } finally {
      freeDbResouce(preStatement, null, connection, pool);
    }
  }
Beispiel #4
0
 /**
  * delete a friend relationship
  *
  * @param accountId1 - accountId of first person
  * @param accountId2 - accountId of second person
  * @return true if success
  */
 public static boolean deleteFriend(int accountId1, int accountId2) {
   ConnectionPool pool = ConnectionPool.getInstance();
   Connection connection = pool.getConnection();
   PreparedStatement preStatement = null;
   try {
     String sqlCode =
         "DELETE FROM Friend "
             + "WHERE (accountId1 = ? AND accountId2 = ?) OR "
             + "      (accountId1 = ? AND accountId2 = ?)";
     preStatement = connection.prepareStatement(sqlCode);
     preStatement.setInt(1, accountId1);
     preStatement.setInt(2, accountId2);
     preStatement.setInt(3, accountId2);
     preStatement.setInt(4, accountId1);
     int nRows = preStatement.executeUpdate();
     if (nRows > 0) {
       return true;
     } else {
       return false;
     }
   } catch (SQLException sqle) {
     sqle.printStackTrace();
     return false;
   } finally {
     freeDbResouce(preStatement, null, connection, pool);
   }
 }
Beispiel #5
0
 /**
  * get number of friends
  *
  * @param accountId - accountId of the account
  */
 public static int getNumOfFriends(int accountId) {
   ConnectionPool pool = ConnectionPool.getInstance();
   Connection connection = pool.getConnection();
   PreparedStatement preStatement = null;
   try {
     String sqlCode = "SELECT * FROM Friend " + "WHERE accountId1 = ? OR accountId2 = ?";
     preStatement = connection.prepareStatement(sqlCode);
     preStatement.setInt(1, accountId);
     preStatement.setInt(2, accountId);
     ResultSet resultSet = preStatement.executeQuery();
     if (resultSet.last()) {
       return resultSet.getRow();
     } else {
       return 0;
     }
   } catch (SQLException sqle) {
     sqle.printStackTrace();
     return 0;
   } finally {
     freeDbResouce(preStatement, null, connection, pool);
   }
 }
Beispiel #6
0
  /**
   * get number of common friends between two different users
   *
   * @param accountId1 - accountId of the first person
   * @param accountId2 - accountId of the second person
   * @return number of common friends
   */
  public static int getNumOfCommonFriends(int accountId1, int accountId2) {
    int smallId = Math.min(accountId1, accountId2);
    int bigId = Math.max(accountId1, accountId2);
    ConnectionPool pool = ConnectionPool.getInstance();
    Connection connection = pool.getConnection();
    PreparedStatement preStatement = null;
    try {
      int numOfCommons = 0;

      // find common friends that has the accountId less than two users
      String sqlCode =
          "SELECT * "
              + "FROM Friend as f1, Friend as f2 "
              + "WHERE f1.accountId1 = f2.accountId1 AND "
              + "      f1.accountId2 = ? AND f2.accountId2 = ? ";
      preStatement = connection.prepareStatement(sqlCode);
      preStatement.setInt(1, smallId);
      preStatement.setInt(2, bigId);
      ResultSet resultSet = preStatement.executeQuery();
      if (resultSet.last()) {
        numOfCommons += resultSet.getRow();
      }

      resultSet.close();
      preStatement.close();
      // find common friends that has the accountId between two users' accountId
      sqlCode =
          "SELECT * "
              + "FROM Friend as f1, Friend as f2 "
              + "WHERE f1.accountId2 = f2.accountId1 AND "
              + "      f1.accountId1 = ? AND f2.accountId2 = ? ";
      preStatement = connection.prepareStatement(sqlCode);
      preStatement.setInt(1, smallId);
      preStatement.setInt(2, bigId);
      resultSet = preStatement.executeQuery();
      if (resultSet.last()) {
        numOfCommons += resultSet.getRow();
      }

      resultSet.close();
      preStatement.close();
      // find common friend that has the accountId greater than two users' accountId
      sqlCode =
          "SELECT * "
              + "FROM Friend as f1, Friend as f2 "
              + "WHERE f1.accountId2 = f2.accountId2 AND "
              + "      f1.accountId1 = ? AND f2.accountId1 = ? ";
      preStatement = connection.prepareStatement(sqlCode);
      preStatement.setInt(1, smallId);
      preStatement.setInt(2, bigId);
      resultSet = preStatement.executeQuery();
      if (resultSet.last()) {
        numOfCommons += resultSet.getRow();
      }
      resultSet.close();
      return numOfCommons;
    } catch (SQLException sqle) {
      sqle.printStackTrace();
      return 0;
    } finally {
      freeDbResouce(preStatement, null, connection, pool);
    }
  }