Java program to insert an element to ArrayList using ListIterator Example

ArrayList java Collections interview Questions ListIterator

Java program to insert an element to ArrayList using ListIterator Example

Kris Kimcil 03.30 Komentar

1.Basic Java example program to insert element using list iterator to arraylist

1. package com.javaIteratearraylistiterator;
2.  
3. import java.util.ArrayList;
4. import java.util.Collections;
5. import java.util.Iterator;
6.  
7. public class IterateListIteratorArrayList{
8.  
9. public static void main(String[] args) {
10.   
11. //create an ArrayList object
12. ArrayList<String> arrayList = new ArrayList();
13.        
14. //Add elements to Arraylist
15.  
16. arrayList.add("A");
17. arrayList.add("B");
18. arrayList.add("C");
19. arrayList.add("D");
20. arrayList.add("F");
21. arrayList.add("F");
22. arrayList.add("G");
23. arrayList.add("H");
24. arrayList.add("I");
25.     
26.         
27.  /*
28. Get a ListIterator object for ArrayList using
29. istIterator() method.
30. */
31.   
32. System.out.println("Before inserting element");
33.  
34. for(int intIndex = 0; intIndex < arrayList.size(); intIndex++)
35.               System.out.println(arrayList.get(intIndex)); 
36. ListIterator itr = arrayList.listIterator();
37.        
38. /*
39.       Use void add(Object o) method of ListIterator to add or insert an element
40.       to List. It adds an element just before the element that would have
41.       been returned by next method call and after the element that would have
42.       returned by previous call.
43.     */
44.    
45.     itr .next();
46.        
47.     //Add an element
48.     itr .add("Added Element");
49.     /*
50.  
51. System.out.println("After inserting element .");
52.  
53. for(int intIndex = 0; intIndex < arrayList.size(); intIndex++)
54.               System.out.println(arrayList.get(intIndex));   
55.  
56. }
57. }
     

Output:

1. Before inserting element
2. A
3. B
4. C
5. D
6. F
7. F
8. G
9. H
10. I
11. After inserting element .
12. A
13. Added Element
14. B
15. C
16. D
17. F
18. F
19. G
20. H
21. I

Baca selengkapnya

How to Iterate ArrayList using Java ListIterator Example

ArrayList Concept and Interview Questions

How to Iterate ArrayList using Java ListIterator Example

Kris Kimcil 23.21 Komentar

1.Basic Java example program to iterate arraylist elements using list iterator

1. package com.javaIteratearraylistiterator;
2.  
3. import java.util.ArrayList;
4. import java.util.Collections;
5. import java.util.Iterator;
6.  
7. public class IterateListIteratorArrayList{
8.  
9. public static void main(String[] args) {
10.   
11. //create an ArrayList object
12. ArrayList<String> arrayList = new ArrayList();
13.        
14. //Add elements to Arraylist
15.  
16. arrayList.add("A");
17. arrayList.add("B");
18. arrayList.add("C");
19. arrayList.add("D");
20. arrayList.add("F");
21. arrayList.add("F");
22. arrayList.add("G");
23. arrayList.add("H");
24. arrayList.add("I");
25.     
26.         
27.  /*
28. Get a ListIterator object for ArrayList using
29. istIterator() method.
30. */
31.  
32. ListIterator itr = arrayList.listIterator();
33.        
34. /*
35. Use hasNext() and next() methods of ListIterator to iterate through
36. the elements in forward direction.
37. */
38.  
39. System.out.println("Iterating through ArrayList elements in forward  direction...");
40.  
41. while(itr.hasNext())
42. System.out.println(itr.next());
43.      
44. /*Use hasPrevious() and previous() methods of ListIterator to iterate through
45. the elements in backward direction.*/
46.  
47. System.out.println("Iterating through ArrayList elements in backward   direction...");
48.         
49.  
50. while(itr.hasPrevious())
51. System.out.println(itr.previous()); 
52.   
53. }
54.  
55. }
     

Output:

1. Iterating through ArrayList elements in forward  direction...
2. A
3. B
4. C
5. D
6. F
7. F
8. G
9. H
10. I
11. Iterating through ArrayList elements in backward   direction...
12. I
13. H
14. G
15. F
16. F
17. D
18. C
19. B
20. A

Baca selengkapnya

How to sort arraylist of strings alphabetically java

ArrayList java Collections interview Questions

How to sort arraylist of strings alphabetically java

Kris Kimcil 22.48 Komentar

1.Basic Java example program to sort arraylist of strings

1. package com.javasortarraylistofobjects;
2.  
3. import java.util.ArrayList;
4. import java.util.Collections;
5. import java.util.Iterator;
6.  
7. public class SortArrayList{
8.  
9. public static void main(String[] args) {
10.   
11. //create an ArrayList object
12. ArrayList<String> arrayList = new ArrayList();
13.        
14. //Add elements to Arraylist
15.         
16. arrayList.add("A"); 
17. arrayList.add("C");
18. arrayList.add("D");
19. arrayList.add("Z");
20. arrayList.add("F");
21. arrayList.add("J");
22. arrayList.add("K");
23. arrayList.add("M");
24. arrayList.add("L");
25. arrayList.add("O");
26.        
27.         
28.  System.out.println("Before sorting ArrayList ...");
29.  Iterator itr=arrayList.iterator();
30.         
31. while (itr.hasNext()) {
32.  
33. System.out.println(itr.next());
34.      
35. }
36.  
37.        
38.  /*
39.  To sort an ArrayList object, use Collection.sort method. This is a
40.   static method. It sorts an ArrayList object's elements into ascending order.
41. */
42.   Collections.sort(arrayList);
43.      
44.   System.out.println("After sorting ArrayList ...");
45.        
46.     
47.         
48. Iterator itr1=arrayList.iterator();
49.         
50. while (itr1.hasNext()) {
51. 
    
52. System.out.println(itr1.next());
53.             
54. }
55.     
56.   
57. }
58. }
     

Output:

1. Before sorting ArrayList ...
2. A
3. C
4. D
5. Z
6. F
7. J
8. K
9. M
10. L
11. O
12. After sorting ArrayList ...
13. A
14. C
15. D
16. F
17. J
18. K
19. L
20. M
21. O
22. Z

Baca selengkapnya

Java Program to Sort elements of Java ArrayList Example

ArrayList java Collections interview Questions

Java Program to Sort elements of Java ArrayList Example

Kris Kimcil 22.21 Komentar

1.Basic Java example program to sort arraylist of integers

1. package com.javasortarraylistofobjects;
2.  
3. import java.util.ArrayList;
4. import java.util.Collections;
5. import java.util.Iterator;
6.  
7. public class SortArrayList{
8.  
9. public static void main(String[] args) {
10.   
11. //create an ArrayList object
12.  ArrayList<Integer> arrayList = new ArrayList<Integer>();
13.        
14.  //Add elements to Arraylist
15. arrayList.add(10);
16. arrayList.add(7);
17. arrayList.add(11);
18. arrayList.add(4);
19. arrayList.add(9);
20. arrayList.add(6);
21. arrayList.add(2);
22. arrayList.add(8);
23. arrayList.add(5);
24. arrayList.add(1);
25.         
26.         
27.  System.out.println("Before sorting ArrayList ...");
28.  Iterator itr=arrayList.iterator();
29.         
30. while (itr.hasNext()) {
31.  
32. System.out.println(itr.next());
33.      
34. }
35.  
36.        
37.  /*
38.  To sort an ArrayList object, use Collection.sort method. This is a
39.   static method. It sorts an ArrayList object's elements into ascending order.
40. */
41.   Collections.sort(arrayList);
42.      
43.   System.out.println("After sorting ArrayList ...");
44.        
45.     
46.         
47. Iterator itr1=arrayList.iterator();
48.         
49. while (itr1.hasNext()) {
50. 
    
51. System.out.println(itr1.next());
52.             
53. }
54.     
55.   
56. }
57. }
     

Output:

1. Before sorting ArrayList ...
2. 10
3. 7
4. 11
5. 4
6. 9
7. 6
8. 2
9. 8
10. 5
11. 1
12. After sorting ArrayList ...
13. 1
14. 2
15. 4
16. 5
17. 6
18. 7
19. 8
20. 9
21. 10
22. 11
    

Baca selengkapnya

Basic Java example program to replace an element at specified index arraylist

ArrayList java Collections interview Questions

Basic Java example program to replace an element at specified index arraylist

Kris Kimcil 22.03 Komentar

1.Basic java Example program to replace an element at specified index java arrayList.

1. package com.instanceofjavaforus;
2. import java.util.ArrayList;
3.  
4. public class ReplaceArrayList{
5.  
6. public static void main(String[] args) {
7.   
8. //create an ArrayList object
9.  ArrayList<Integer> arrayList = new ArrayList<Integer>();
10.        
11.         //Add elements to Arraylist
12.         arrayList.add(1);
13.         arrayList.add(2);
14.         arrayList.add(3);
15.         arrayList.add(4);
16.         arrayList.add(5);
17.         arrayList.add(6);
18.         arrayList.add(7);
19.         arrayList.add(8);
20.         arrayList.add(9);
21.         arrayList.add(10);
22.         
23.  
24.   /*
25.   To replace an element at the specified index of ArrayList use
26.   Object set(int index, Object obj) method.
27.   This Object set(int index, Object obj) method replaces the specified element at the specified
28.   index in the ArrayList and returns the element previously at the specified position.
29.   */
30.  
31.  arrayList.set(1,23);
32.      
33.  System.out.println("ArrayList contains...");
34.  Iterator itr=arrayList.iterator();
35.  
36. while (itr.hasNext()) {
37.  
38.  System.out.println(itr.next());
39.  
40.  }
41.   
42. }
43. }
     

Output:

1. ArrayList contains...
2. 1
3. 23
4. 3
5. 4
6. 5
7. 6
8. 7
9. 8
10. 9
11. 10

Baca selengkapnya