Java Reference
In-Depth Information
r e s u l t+= ( l i n e ++)+
"|"
;
for
(Cell cell : row)
{
result += cell+
""
;
}
return
result ;
}
The code iterates over all rows of the grid. For each row, it adds to
result
a new line
and the line number. Note that the expression:
result += (line++)+" | ";
means add
the current value of the variable
line
to the variable
result
and then increment the value
of the variable
line
by 1. The line can be rewritten as follows.
result = result + (String)( line) +
"|"
;
line = line+1;
Remember that adding an integer and a string concatenated the integer to the string.
This is why we did not need the explicit cast to
String
in the original expression.
Next, the code iterates over all cells of the row. The statement:
result += cell+" "
is equivalent to
result = result+ cell.toString()+" "
. In other words, the
toString
method for the
cell
object is automatically called to convert the object into a string.
The complete code for the
Board
class is presented next.
import
java . util .
∗
;
public class
Board
{
public static final int
BOARD SIZE = 10;
public static final boolean
HORIZONTAL =
true
;
public static final boolean
VERTICAL =
false
;
public static final
int
[ ] placement =
{
5,4,3,2,2,1,1
}
;
private
Cell [ ] [ ] grid =
new
Cell [BOARDSIZE ] [ BOARD SIZE ] ;
private
Ship [] ships =
new
Ship [ placement . length ] ;
public
String toString()
{
String result=
" 0123456789\n ----------"
;
int
line = 0;
for
(Cell[] row: grid)
{
result+=
"\n"
;
result+= (line++)+
"|"
;
for
(Cell cell: row)
{
result += cell+
""
;
}
return
result ;
}
public
Cell getElement(
int
row ,
int
column)
{
if
((row
>
=0&&row
<
BOARD SIZE) &&
(column
>
=0&&column
<
BOARD SIZE) )
{
return
grid [row][ column];
return null
;
}
