Java Reference
In-Depth Information
120
// determine whether list is empty
121
122
{
123
return
firstNode ==
null
;
// return true if list is empty
124
}
125
126
// output list contents
127
128
{
129
if
(isEmpty())
130
{
131
System.out.printf(
"Empty %s%n"
, name);
132
return
;
133
}
134
135
System.out.printf(
"The %s is: "
, name);
136
ListNode<T> current = firstNode;
137
138
// while not at end of list, output current node's data
139
while
(current !=
null
)
140
{
141
System.out.printf(
"%s "
, current.data);
142
current = current.nextNode;
143
}
144
145
System.out.println();
146
}
147
}
// end class List<T>
public boolean
isEmpty()
public void
print()
Fig. 21.3
|
ListNode
and
List
class declarations. (Part 4 of 4.)
1
// Fig. 21.4: EmptyListException.java
2
// Class EmptyListException declaration.
3
package
com.deitel.datastructures;
4
5
public class
EmptyListException
extends
RuntimeException
6
{
7
// constructor
8
public
EmptyListException()
9
{
10
this
(
"List"
);
// call other EmptyListException constructor
11
}
12
13
// constructor
14
public
EmptyListException(String name)
15
{
16
super
(name +
" is empty"
);
// call superclass constructor
17
}
18
}
// end class EmptyListException
Fig. 21.4
|
Class
EmptyListException
declaration.
