Heidi Atwood

OK, and thank you for the explanation. I understand that factor can take on whatever the value of the variable is that it is being passed in the method. My confusion was that nowhere in the code did I see where y was specifically being passed into the method doStuff, I didn't understand you were using that as an example. I apologize for not getting it sooner.

Heidi

When a method is called, it may (or may not) have one or more "parameters" passed to it. The place from which the method is called puts one or more names of variables in the parentheses following the method name, and the values of those are "passed to" the method.

I knew this, sorry, I've only been studying Java for about a month and I can't seem to keep hold of all the odds and ends. That makes much more sense now, but if this is the line of code in which doStuff is being called:

result = result + obs[x].doStuff(x);

wouldn't the variable being passed be x? I'm sorry for being so thickheaded!!!

Heidi

Wait, I STILL don't get where we find the value of factor? HELP!

Holy moses, thank you so much for that explanation! I had worked this out on paper, I had typed it into Eclipse, I had changed the variable names to make it more understandable but it wasn't until I read through your explanation that I got where ivar was getting its value!! Coderanch to the rescue again. Thanks so much!

Heidi

ACK! Never mind - just discovered this has already been asked about ten times. Sorry!

I've been working my way through Headfirst Into Java and got to the puzzle in Chapter Five and got stumped. I changed the variable names to something less confusing and I can follow most of the code, but I don't understand where in the PuzzleTest class that the int variable factor gets made equal to a number that can be used to complete the calculation. I know I'm pushing the "no question to small" envelope but I've been staring at it since last night and would appreciate any pointers? Thanks for any help! Here is the main class (and yes, I know I renamed them backwards with the main being Puzzle and the method class being PuzzleTest)...

public static void main(String[] args) { PuzzleTest[] myList = new PuzzleTest[6]; int y = 1; int x = 0; int result = 0; while (x < 6) { myList[x] = new PuzzleTest(); myList[x].count = y; y = y * 10; x = x + 1; } x = 6; while (x > 0) { x = x - 1; result = result + myList[x].doStuff(x); } System.out.println("result " + result); } }

And here is the method class...

package objects; public class PuzzleTest { int count; public int doStuff(int factor) { if (count > 100) { return count * factor; } else { return count * (5 - factor); } } }

Heidi

Oh man!!! Talk about obvious mistakes and still not getting a clue - thank you, Henry, for gently trying to get me to see it and thanks Tony, for making sure I saw it.

Heidi

OK, first off, thanks for the superspeedy response! Second, when I try to run your code, it hangs up just like mine. When I compare line by line I'm still missing the difference - sorry if my formatting was wonky - I was using the default (or thought I did) shift-control F in Eclipse to get everything lined up correctly.

I've been staring at this code for an hour and I can't figure out why it's hanging up. The while loop never happens. I'm sure it's horribly obvious but if someone could point out the problem I'd be grateful or at least give me a hint. The result is supposed to be: a-b c-d

package practice; public class Scramble { public static void main(String[] args) { int x = 3; System.out.print(x); while (x > 0) { if (x > 2) { System.out.print("a");} } x = x - 1; System.out.print("-"); if (x == 2) { System.out.print("b c"); } if (x == 1) { System.out.print("d"); x = x - 1; } }}

Well, I got a little further and then got stuck again. I'm able to write to the data base, and retrieve from it, but I'm stuck on understanding how to compare user input to existing data to confirm someone is a registered user. Let me preface this by saying I'm totally winging it and don't have a good understanding of what's happening. Here's what I've got in the main launcher class which isn't working...

ResultSet resultSet = userScreenConnector.fetchFilteredRows(logIn, args); if (login!= null && login.equals(resultSet.getString("login"))) { System.out.println(resultSet.getString("login")); } System.out.println(RegUser.PASSWORD_ENTRY); String pWord = input.next(); System.out.println();

And here is the piece in the other class.

public static final String SEARCH_REGISTERED_USER = "SELECT * FROM `Catalyst6`.'contact info` where login=?";

And finally the section for the prepared statement.
public ResultSet fetchFilteredRows(String filteredSelect, String[] params) throws SQLException { PreparedStatement preparedStatement = connection .prepareStatement(filteredSelect); int index = 1; for (String param : params) { preparedStatement.setString(index, param); index++; }

I'm not sure how well I can explain, but I'll try. Let me take another look at the code and get my thoughts together, lol...

Heidi

Never mind - figured it out!!

I'm working on code that is for an eBookstore project in my class. I have it set up so the user is asked if they are a registered user. If they answer y (for yes), I want to be able to be able to check their login name against an existing database. I've managed to write to the table and I can read from it, but no idea how to actually search it. I'm going to try and put my code in (yes, it's a dogs breakfast) because I don't have a great grasp on how this process works so please forgive me if it's messed up! :-)

package bookstoreClasses; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; public class Connector { private Connection connection; public Connector() { try { Class.forName("com.mysql.jdbc.Driver").newInstance(); connection = DriverManager .getConnection("jdbc:mysql://localhost:3306?user=root&password=Skyleris12!"); } catch (Exception e) { e.printStackTrace(); } } public ResultSet fetchRows(String selectStatement) throws SQLException { Statement statement = connection.createStatement(); ResultSet resultSet = statement.executeQuery(selectStatement); return resultSet; } public boolean findEmail(String findStatement, String[] params) throws SQLException{ PreparedStatement preparedStatement = connection.prepareStatement(findStatement); return preparedStatement.execute(); } public boolean insertNewRows(String insertStatement, String[] params) throws SQLException { PreparedStatement preparedStatement = connection .prepareStatement(insertStatement); int index = 1; for (String param : params) { preparedStatement.setString(index, param); index++; } return preparedStatement.execute(); } public ResultSet readRows(String tableName) throws SQLException { Statement statement = connection.createStatement(); ResultSet resultSet = statement.executeQuery("SELECT * FROM Catalyst6." + tableName + "; "); return resultSet; } }

Ed Dablin wrote:

Heidi Atwood wrote:Hi, I'm in a Java developers boot camp and I'm coming in with zero programming experience. Are there any tutorials on YouTube that are particularly suited to total newbies? I just ended week two of what is supposed to be a fourteen - twenty week program and to say I'm overwhelmed is an understatement. I have Head First Java and a couple other books and those are helping a lot, but I can use anything extra to get me through this. Thanks again - I've already learned a lot just reading through threads, including the difference between methods and constructors, which had completely baffled me!

Heidi

Speaking as one beginner to another, I have found the quality of many YouTube videos to be very poor. I subscribed to www.lynda.com and it is worth every penny. The instructors have obviously rehearsed the carefully written scripts so there are no "ers", "ums" or errors. They move along at a cracking pace, but that's ok because you can replay them over and over. (I have no connection with lynda.com except as a satisfied customer)

Good to know - I'll definitely check it out. Thanks for the info!

Heidi

Paul Witten wrote:

Heidi Atwood wrote:Thanks so much everyone!

I remember a pro guitarist telling me about his horrible Guitar Institute Boot Camp that lasted a couple of months, live in, ten hours a day theory cramming and playing time, seven days a week. He said it was trauma on the mind as it was impossible to absorb everything. The information came too fast for normal absorption. But he swore by the experience later, saying that his mind took in much more than he realized at that time. A few months would go by and he'd remember something that he had no daily memory of learning.

Educators will tell you that the best way to learn is through purposeful repetition. It's hard to repeat much during a bootcamp. I don't mean repeat once or twice - I mean repeat as many times as you need to have it "sink in". Sometimes that can take quite a few repetitions as you learn incrementally through each repetition. Finally you get it, the light goes on, and you're done forever with that.

I'd rather play with while loops for a week and discover all there is to know about them than to play for a few hours, say "I now know while loops" and rush on to the next item.

I agree, but unfortunately the boot camp is my way to a job, something I've been looking for since February... :-( So I'm trying to gain as much foundation as I can throughout the process.

Heidi