Hi all, I have this functions and need to make it one function. The only difference is type of input variable sourceColumnValue. This variable can be String or Integer but the return value of function must be always Integer. I know I need to use Generics but can't do it.

    public Integer selectReturnInt(String tableName, String sourceColumnName, String sourceColumnValue, String targetColumnName) {
    Integer returned = null;
    String query = "SELECT "+targetColumnName+" FROM "+tableName+" WHERE "+sourceColumnName+"='"+sourceColumnValue+"' LIMIT 1";

    try {
        Connection connection = ConnectionManager.getInstance().open();
        java.sql.Statement statement = connection.createStatement();
        statement.execute(query.toString());
        ResultSet rs = statement.getResultSet();
        while(rs.next()){
            returned = rs.getInt(targetColumnName);
        }

        rs.close();
        statement.close();
        ConnectionManager.getInstance().close(connection);
    } catch (SQLException e) {
        System.out.println("???????? ?? ???? ?? ???? ?????????!");
        System.out.println(e);
    }

    return returned;
}


// SELECT (RETURN INTEGER)
public Integer selectIntReturnInt(String tableName, String sourceColumnName, Integer sourceColumnValue, String targetColumnName) {
    Integer returned = null;
    String query = "SELECT "+targetColumnName+" FROM "+tableName+" WHERE "+sourceColumnName+"='"+sourceColumnValue+"' LIMIT 1";

    try {
        Connection connection = ConnectionManager.getInstance().open();
        java.sql.Statement statement = connection.createStatement();
        statement.execute(query.toString());
        ResultSet rs = statement.getResultSet();
        while(rs.next()){
            returned = rs.getInt(targetColumnName);
        }

        rs.close();
        statement.close();
        ConnectionManager.getInstance().close(connection);
    } catch (SQLException e) {
        System.out.println("???????? ?? ???? ?? ???? ?????????!");
        System.out.println(e);
    }

    return returned;
}