Ninu ifiweranṣẹ yii a bo awọn ọna Java ArrayList ti o wọpọ pẹlu awọn apẹẹrẹ koodu fun ọna kọọkan.
Awọn ArrayList
kilasi jẹ ipilẹ resizable kan. A maa nlo ArrayList
nigbati a ko mọ iwọn ti atokọ tẹlẹ.
Awọn ArrayList
kilasi wa ninu java.util
package.
Lati ṣẹda Akojọ Array kan ki o ṣafikun awọn ohun kan si, a ntẹle ohun kan _ _ + _ | ohun pẹlu iru pàtó kan, gẹgẹbi ArrayList
tabi String
.
Ṣe akiyesi Integer
ọna ṣe afikun ohun kan si ipo ti o tẹle ni ArrayList. Wo apeere atẹle lati wo bi a ṣe le ṣafikun ohun kan si itọka kan pato.
add()
Ijade:
import java.util.ArrayList; public class ArrayListTutorial { public static void main(String[] args) {
ArrayList fruitBasket = new ArrayList();
fruitBasket.add('Apple');
fruitBasket.add('Banana');
fruitBasket.add('Grapes');
fruitBasket.add('Orange');
System.out.println(fruitBasket); } }
Lati ṣafikun ohun kan si ipo pàtó kan, a ni lati pese atọka ti o fẹ si [Apple, Banana, Grapes, Orange]
ọna.
add()
Ijade:
import java.util.ArrayList; public class ArrayListTutorial { public static void main(String[] args) {
ArrayList fruitBasket = new ArrayList();
fruitBasket.add('Apple');
fruitBasket.add('Banana');
fruitBasket.add('Grapes');
fruitBasket.add('Orange');
fruitBasket.add(2, 'Melon');
System.out.println(fruitBasket); } }
Awọn [Apple, Banana, Melon, Grapes, Orange]
ọna gba ohun kan pada. A ni lati pese nọmba itọka si get()
ọna.
get()
import java.util.ArrayList; public class ArrayListTutorial { public static void main(String[] args) {
ArrayList fruitBasket = new ArrayList();
fruitBasket.add('Apple');
fruitBasket.add('Banana');
fruitBasket.add('Grapes');
fruitBasket.add('Orange');
System.out.println(fruitBasket.get(1)); } }
Lati yọ ohun kan kuro, a lo Banana
ọna. A ni lati pese nọmba itọka.
remove()
Ijade:
import java.util.ArrayList; public class ArrayListTutorial { public static void main(String[] args) {
ArrayList fruitBasket = new ArrayList();
fruitBasket.add('Apple');
fruitBasket.add('Banana');
fruitBasket.add('Grapes');
fruitBasket.add('Orange');
fruitBasket.remove(0);
System.out.println(fruitBasket); } }
Awọn [Banana, Grapes, Orange]
ọna yọ gbogbo awọn nkan kuro ninu clear()
.
ArrayList
import java.util.ArrayList; public class ArrayListTutorial { public static void main(String[] args) {
ArrayList fruitBasket = new ArrayList();
fruitBasket.add('Apple');
fruitBasket.add('Banana');
fruitBasket.add('Grapes');
fruitBasket.add('Orange');
fruitBasket.clear();
System.out.println(fruitBasket); } }
[]
Ijade:
import java.util.ArrayList; public class ArrayListTutorial { public static void main(String[] args) {
ArrayList fruitBasket = new ArrayList();
fruitBasket.add('Apple');
fruitBasket.add('Banana');
fruitBasket.add('Grapes');
fruitBasket.add('Orange');
System.out.println(fruitBasket.size()); } }
4
Ijade:
import java.util.ArrayList; public class ArrayListTutorial { public static void main(String[] args) {
ArrayList fruitBasket = new ArrayList();
fruitBasket.add('Apple');
fruitBasket.add('Banana');
fruitBasket.add('Grapes');
fruitBasket.add('Orange');
for (int i = 0; i < fruitBasket.size(); i++) {
System.out.println(fruitBasket.get(i));
} } }
Apple Banana Grapes Orange
Ijade:
import java.util.ArrayList; public class ArrayListTutorial { public static void main(String[] args) {
ArrayList fruitBasket = new ArrayList();
fruitBasket.add('Apple');
fruitBasket.add('Banana');
fruitBasket.add('Grapes');
fruitBasket.add('Orange');
for (String i : fruitBasket) {
System.out.println(i);
} } }
Apple Banana Grapes Orange
Ijade:
import java.util.ArrayList; public class ArrayListTutorial { public static void main(String[] args) {
ArrayList numbers = new ArrayList();
numbers.add(10);
numbers.add(20);
numbers.add(30);
numbers.add(40);
for (int i : numbers) {
System.out.println(i);
} } }
Awọn 10 20 30 40
ọna rọpo ohun kan pẹlu ohun miiran ti a pese. A ni lati ṣọkasi itọka ti nkan ti a fẹ lati ropo.
replace()
Ijade:
import java.util.ArrayList; public class ArrayListTutorial { public static void main(String[] args) {
ArrayList fruitBasket = new ArrayList();
fruitBasket.add('Apple');
fruitBasket.add('Banana');
fruitBasket.add('Grapes');
fruitBasket.add('Orange');
fruitBasket.set(3, 'Peach')
for (String i : fruitBasket) {
System.out.println(i);
} } }
Awọn #before replace [Apple, Banana, Grapes, Orange] #after replace [Apple, Banana, Grapes, Peach]
ọna wa ninu shuffle()
kilasi ati pe a lo lati ṣe idapọ laileto ti awọn ohun ArrayList.
Collections
Ijade:
import java.util.ArrayList; import java.util.ArrayList; import java.util.Collections; public class ArrayListTutorial { public static void main(String[] args) {
ArrayList fruitBasket = new ArrayList();
fruitBasket.add('Apple');
fruitBasket.add('Banana');
fruitBasket.add('Grapes');
fruitBasket.add('Orange');
System.out.println(fruitBasket);
Collections.shuffle(fruitBasket);
System.out.println(fruitBasket); } }
#before shuffle [Apple, Banana, Grapes, Orange] #after shuffle [Grapes, Orange, Banana, Apple]
Ijade:
import java.util.ArrayList; import java.util.ArrayList; import java.util.Collections; public class ArrayListTutorial { public static void main(String[] args) {
ArrayList fruitBasket = new ArrayList();
fruitBasket.add('Orange');
fruitBasket.add('Apple');
fruitBasket.add('Grapes');
fruitBasket.add('Banana');
System.out.println(fruitBasket);
Collections.sort(fruitBasket);
System.out.println(fruitBasket); } }
#before sort [Orange, Apple, Grapes, Banana] #after sort [Apple, Banana, Grapes, Orange]
Ijade:
public class ArrayListTutorial { public static void main(String[] args) {
ArrayList fruitBasket = new ArrayList();
fruitBasket.add('Apple');
fruitBasket.add('Banana');
fruitBasket.add('Grapes');
fruitBasket.add('Orange');
System.out.println(fruitBasket);
Collections.reverse(fruitBasket);
System.out.println(fruitBasket); } }
#original list [Apple, Banana, Grapes, Orange] #after reverse [Orange, Grapes, Banana, Apple]
Ijade:
import java.util.ArrayList; public class ArrayListTutorial { public static void main(String[] args) {
ArrayList fruitBasket = new ArrayList();
fruitBasket.add('Apple');
fruitBasket.add('Banana');
fruitBasket.add('Grapes');
fruitBasket.add('Orange');
String[] fruitArray = new String[fruitBasket.size()];
fruitBasket.toArray(fruitArray);
for (String i : fruitArray) {
System.out.println(i);
} } }
Apple Banana Grapes Orange
Ijade:
import java.util.ArrayList; import java.util.Collections; public class ArrayListTutorial { public static void main(String[] args) {
ArrayList fruitBasket = new ArrayList();
fruitBasket.add('Apple');
fruitBasket.add('Banana');
fruitBasket.add('Grapes');
fruitBasket.add('Orange');
System.out.println(fruitBasket1);
Collections.swap(fruitBasket, 1, 3);
System.out.println(fruitBasket); } }
#before swap [Apple, Banana, Grapes, Orange] #after swap [Apple, Orange, Grapes, Banana]
Ijade:
import java.util.ArrayList; public class ArrayListTutorial { public static void main(String[] args) {
ArrayList fruitBasket1 = new ArrayList();
ArrayList fruitBasket2 = new ArrayList();
fruitBasket1.add('Apple');
fruitBasket1.add('Banana');
fruitBasket1.add('Grapes');
fruitBasket1.add('Orange');
fruitBasket2.add('Melon');
fruitBasket2.add('Strawberries');
fruitBasket1.addAll(fruitBasket2);
System.out.println(fruitBasket1); } }
Ni ipo yii o rii awọn apẹẹrẹ oriṣiriṣi ti awọn iṣẹ ti o wọpọ lori Java ArrayLists.