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مخصوصا این قسمت خروجی رو : List with two new elements: yellow red green yellow
/ ممنونم /
1 // Fig. 7.24: ArrayListCollection.java
2 // Generic ArrayList<T> collection demonstration.
3 import java.util.ArrayList;
4
5 public class ArrayListCollection
6 {
7 public static void main( String[] args )
8 {
9 // create a new ArrayList of Strings with an initial capacity of 10
10 ArrayList< String > items = new ArrayList< String >();
11
12 items.add( "red" ); // append an item to the list
13 items.add( 0, "yellow" ); // insert the value at index 0
14
15 // header
16 System.out.print(
17 "Display list contents with counter-controlled loop:" );
18
19 // display the colors in the list
20 for ( int i = 0; i < items.size(); i++ )
21 System.out.printf( " %s", items.get( i ) );
22
23 // display colors using foreach in the display method
24 display( items,
25 "\nDisplay list contents with enhanced for statement:" );
26
27 items.add( "green" ); // add "green" to the end of the list
28 items.add( "yellow" ); // add "yellow" to the end of the list
29 display( items, "List with two new elements:" );
30
31 items.remove( "yellow" ); // remove the first "yellow"
32 display( items, "Remove first instance of yellow:" );
33
34 items.remove( 1 ); // remove item at index 1
35 display( items, "Remove second list element (green):" );
36
37 // check if a value is in the List
38 System.out.printf( "\"red\" is %sin the list\n",
39 items.contains( "red" ) ? "": "not " );
40
41 // display number of elements in the List
42 System.out.printf( "Size: %s\n", items.size() );
43 } // end main
44
45 // display the ArrayList's elements on the console
46 public static void display( ArrayList< String > items, String header )
47 {
48 System.out.print( header ); // display header
49
50 // display each element in items
51 for ( String item : items )
52 System.out.printf( " %s", item );
53
54 System.out.println(); // display end of line
55 } // end method display
56 } // end class ArrayListCollection
خروجی :
Display list contents with counter-controlled loop: yellow red
Display list contents with enhanced for statement: yellow red
List with two new elements: yellow red green yellow
Remove first instance of yellow: red green yellow
Remove second list element (green): red yellow
"red" is in the list
Size: 2
