Java Reference
In-Depth Information
3
public class
TestArrayList {
4
public static void
main(String[] args) {
5
// Create a list to store cities
ArrayList<String> cityList =
new
ArrayList<String>();
6
7
8
create
ArrayList
// Add some cities in the list
9
10
// cityList now contains [London]
11 cityList.add(
"Denver"
);
12
// cityList now contains [London, Denver]
13 cityList.add(
"Paris"
);
14
// cityList now contains [London, Denver, Paris]
15 cityList.add(
"Miami"
);
16
// cityList now contains [London, Denver, Paris, Miami]
17 cityList.add(
"Seoul"
);
18
// Contains [London, Denver, Paris, Miami, Seoul]
19 cityList.add(
"Tokyo"
);
20
cityList.add(
"London"
);
add element
// Contains [London, Denver, Paris, Miami, Seoul, Tokyo]
21
22 System.out.println(
"List size? "
+
cityList.size()
);
list size
23 System.out.println(
"Is Miami in the list? "
+
24 );
25 System.out.println(
"The location of Denver in the list? "
26 + );
27 System.out.println(
"Is the list empty? "
+
28
cityList.contains(
"Miami"
)
contains element?
element index
cityList.indexOf(
"Denver"
)
is empty?
cityList.isEmpty()
);
// Print false
29
30
// Insert a new city at index 2
31 cityList.add(
2
,
"Xian"
);
32
// Contains [London, Denver, Xian, Paris, Miami, Seoul, Tokyo]
33
34
// Remove a city from the list
cityList.remove(
"Miami"
);
remove element
35
36
// Contains [London, Denver, Xian, Paris, Seoul, Tokyo]
37
38
// Remove a city at index 1
39 cityList.remove(
1
);
40
remove element
// Contains [London, Xian, Paris, Seoul, Tokyo]
41
42
// Display the contents in the list
43 System.out.println(cityList.toString());
44
45
// Display the contents in the list in reverse order
46
for
(
int
i = cityList.size() -
1
; i >=
0
; i--)
47 System.out.print(
toString()
cityList.get(i)
+
" "
);
get element
48 System.out.println();
49
50
// Create a list to store two circles
51 ArrayList<CircleFromSimpleGeometricObject> list
52 =
new
ArrayList<CircleFromSimpleGeometricObject>();
53
54
// Add two circles
55 list.add(
new
CircleFromSimpleGeometricObject(
2
));
56 list.add(
new
CircleFromSimpleGeometricObject(
3
));
57
58
// Display the area of the first circle in the list
59 System.out.println(
"The area of the circle? "
+
60 ((CircleFromSimpleGeometricObject)list.get(
0
)).getArea());
61 }
62 }
create
ArrayList
