Java Reference
In-Depth Information
float[][] matrix = { { 1.0F, 2.0F, 3.0F }, { 4.0F, 5.0F,
6.0F }};
for (int row = 0; row < matrix.length; row++)
{
for (int col = 0; col < matrix[row].length; col++)
System.out.print(matrix[row][col]+" ");
System.out.print("\n");
}
Expression
matrix.length
returns the number of rows in this tabular array. For
each row, expression
matrix[row].length
returns the number of columns for
that row. This latter expression suggests that each row can have a different number of
columns, although each row has the same number of columns in the example.
System.out.print()
iscloselyrelatedto
System.out.println()
.Unlike
the latter method,
System.out.print()
outputs its argument without a trailing
newline.
This example generates the following output:
1.0 2.0 3.0
4.0 5.0 6.0
While Statement
ThewhilestatementrepeatedlyexecutesastatementwhileitsBooleanexpressioneval-
uates to true. This statement has the following syntax:
while (
Boolean expression
)
statement
While consists of reserved word
while
, followed by a parenthesized
Boolean
expression
header, followed by a
statement
to repeatedly execute.
Thewhilestatementfirstevaluatesthe
Boolean expression
.Ifitistrue,while
executes the other
statement
. Once again, the
Boolean expression
is evalu-
ated. If it is still true, while re-executes the
statement
. This cyclic pattern continues.
Promptingtheusertoenteraspecificcharacterisonesituationwherewhileisuseful.
Forexample,supposethatyouwanttoprompttheusertoenteraspecificuppercaselet-
ter or its lowercase equivalent. The following example provides a demonstration:
int ch = 0;
while (ch != 'C' && ch != 'c')
{
