Printing Issues
/** Print the table. */
publicvoid print()
{
System.out.println("");
System.out.println("P = Piles : B = Blocks");
System.out.println("");
System.out.println("Pile : Block");
for (int pile = 0; pile < piles.length; pile++){
System.out.println("Pile " + pile +": " + piles[pile]);
}
}
this code prints this
P = Piles : B = Blocks
Pile : Block
Pile 0: Pile@16a9b9c
Pile 1: Pile@e2291
Pile 2: Pile@1ff92f5
Pile 3: Pile@9505f
Pile 4: Pile@17ba38f
though what i need is something that looks like this
Pile : Block
Pile 0: 0
Pile 1: 1
Pile 2: 2
Pile 3: 3
Pile 4: 4
the idea is so i can take one block from one pile and stack it on another block!! but i cant do that unitll i get rid of the "Pile@17ba38f"
it seems to me that it print the pile ok but not the ArrayList of blocks any ideas
[1385 byte] By [
JohnnyMaca] at [2007-10-3 3:35:43]
Your Pile class has to have a toString() method where it describes itself.class Pile {
private String name;
private int size;
// other stuff
public String toString() {
return name + " size=" + size;
}
}
You can put whatever you like in the toString() method - this is just an
example. If you don't define your own toString() then java uses the default which
is to print out a sort of "address" that the pile has.
public class Table
{
private int NPILES;// the number of piles
private Pile[] piles; // the array of piles
/** Create a table and initialise the array piles.
* For every pile created create a block
*/
public Table(int npiles)
{
// Initialise NPILES
NPILES = npiles;
// Create the array of size NPILES
piles = new Pile[NPILES];
for (int i = 0; i < NPILES; i++) {
Pile pile = new Pile();
Block block = new Block(i);
piles[i] = new Pile();
}
}
thats my class the block is an integer i dont understanfd what u mean below!! sorry im a bit new to java
The problem is in the Pile class, not the Table class. It will (probably) be in afile called Pile.java, and probably not in Table.java.Once you have found the Pile class add a toString() method like the one in myexample.
ok i added that to the pile class i thought id just show u what it looks like to see if ive done anthing wrong!!
cheers
import java.util.ArrayList;
import java.util.Iterator;
/**
* Write a description of class Pile here.
*
* @author (your name)
* @version (a version number or a date)
*/
public class Pile
{
private ArrayList<Block> blocks;
private String name;
private int size;
/**
* Creates a New pile and initialises its state
* Creates a block with a pile
*/
public Pile()
{
blocks = new ArrayList<Block>();
}
/**
* Add block to a pile
*/
public void addBlock(Block block)
{
blocks.add(block);
}
/**
* To string meathod
*/
public String toString() {
return name + " size=" + size;
}
/**
* Remove a block from a pile
*/
public void removeBlock(int blockNumber)
{
if (blockNumber <0){
//this is not a valid block number, so do nothing
}
else if (blockNumber < pileSize()){
//This is a valid block number, so we can remove it
blocks.remove(blockNumber);
}
else{
//this is not a valid block number so do nothing
}
}
/**
* Return the size of a pile
*/
public int pileSize()
{
return blocks.size();
}
/** Returns the position of a block with number n if present, else -1. */
public int search(int n) {
int pos = 0;
boolean found = false;
while (! found && pos < blocks.size()) {
if (blocks.get(pos).getNumber() == n)
found = true;
else
pos = pos + 1;
}
if (found)
return pos;
else
return -1;
}
/**
* Print a pile
*/
public void DisplayPile()
{
for (Block block : blocks){
System.out.println(block.getNumber());
}
}
}
It was meant as an example!
Remove the name and size declarations. And replace toString() withpublic String toString()
{
StringBuilder buf = new StringBuilder();
for (Block block : blocks){
buf.append(block.getNumber()).append(" ");
}
return buf.toString();
}
As you can see the code is similar to what you are already using to describe
the Pile. (The difference is that prints the contents in one line)
edit: sorry about changing this after posting it!
missin return statementMessage was edited by: JohnnyMac
>Now it prints the size is nullwhich became> missin return statementSee my previous post - which I think I've finally got right.
Yeah i got that and changed it but my table prints
but its still not printing my blocks
>> it would need to get the block index from the arraylist and print it in the pile!! is that right?
Message was edited by:
JohnnyMac
Message was edited by:
JohnnyMac
> but its still not printing my blocks
What do you mean by "not printing my blocks"? Bear in mind that I haven't
seen your Block class.
What my suggestion does is print the result of calling the getNumber()
method of each block in the Pile. If you something other than the this to
be shown, then add the code to Pile's toString() to add whatever it is
that you want to have printed.
Or you could write a toString() method for the Block class and use that
within the Pile's toString() method.
> it would need to get the block index from the arraylist and print it in the
> pile!! is that right?
The iterator will return process each Block in the standard order (starting
from index 0 and increasing), so I don't you have to print the index along
with the block's description. But, again, that is up to you.
Now im back at square one it wont add my block to the pile when i print any ideas
Yeah im not tryin to print the blocks description im tryin to print so when the table class initialises a pile say
pile 0 :
it creates block 0 as well and prints it as so
pile 0 : block 0 or just
0:0
1:1
2:2
3:3
4:4
an so on, i dont think u need to enter a block descrpiption everything is done in the table class
> but its still not printing my blocks
>>What my suggestion does is print the result of calling the getNumber()
method of each block in the Pile. If you something other than the this to
be shown, then add the code to Pile's toString() to add whatever it is
that you want to have printed.
>>so what i should do is create a meathod that gets the index number of the block ArrayList and print it?
then call the meathod in ur suggestion. do u think that will work
JohnnyMac
