Metòd Java ArrayList ak egzanp

Nan pòs sa a nou kouvri metòd ki pi komen Java ArrayList ak egzanp kòd pou chak metòd.

ArrayList klas se yon etalaj rdimansyonabl. Nou tipikman itilize ArrayList lè nou pa konnen gwosè lis la davans.

ArrayList klas la nan java.util pake.




Ki jan yo kreye yon ArrayList

Pou kreye yon ArrayList epi ajoute atik nan li, nou enstansye yon ArrayList objè ak yon kalite espesifye, tankou String oswa Integer.

Remake byen add() metòd ajoute yon atik nan pozisyon kap vini an nan ArrayList la. Gade pwochen egzanp lan pou wè kijan pou ajoute yon atik nan yon endèks espesifik.


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); } }

Sòti:

[Apple, Banana, Grapes, Orange]

Ki jan yo ajoute yon atik nan yon pozisyon espesifik

Pou ajoute yon atik nan yon pozisyon espesifye, nou dwe bay endèks la vle add() metòd.

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); } }

Sòti:

[Apple, Banana, Melon, Grapes, Orange]

Kouman pou jwenn aksè nan yon atik nan yon ArrayList

get() metòd rekipere yon atik. Nou dwe bay nimewo endèks la get() metòd.


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)); } }
Banana

Ki jan yo retire yon atik ki sòti nan yon ArrayList

Pou retire yon atik, nou itilize remove() metòd. Nou dwe bay nimewo endèks la.

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); } }

Sòti:

[Banana, Grapes, Orange]

Ki jan yo retire tout atik ki sòti nan yon ArrayList

clear() metòd retire tout atik nan yon 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); } }
[]

Kòman ou kapab jwenn gwosè a nan yon 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');
System.out.println(fruitBasket.size()); } }

Sòti:


4

Ki jan yo Loop Atravè yon 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');
for (int i = 0; i < fruitBasket.size(); i++) {
System.out.println(fruitBasket.get(i));
} } }

Sòti:

Apple Banana Grapes Orange

Looping Atravè yon ArrayList Avèk pou-chak

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);
} } }

Sòti:

Apple Banana Grapes Orange

ArrayList Egzanp Avèk Resansman

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);
} } }

Sòti:

10 20 30 40

Kijan pou ranplase yon atik nan yon ArrayList

replace() metòd ranplase yon atik ak yon lòt atik yo bay la. Nou dwe presize endèks la nan atik la nou vle ranplase.


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);
} } }

Sòti:

#before replace [Apple, Banana, Grapes, Orange] #after replace [Apple, Banana, Grapes, Peach]

Kouman Shuffle Atik nan yon ArrayList

shuffle() metòd se nan Collections klas epi yo itilize fè yon chefeul o aza nan atik yo ArrayList.

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); } }

Sòti:

#before shuffle [Apple, Banana, Grapes, Orange] #after shuffle [Grapes, Orange, Banana, Apple]

Ki jan yo Triye Atik nan yon ArrayList

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); } }

Sòti:


#before sort [Orange, Apple, Grapes, Banana] #after sort [Apple, Banana, Grapes, Orange]

Ki jan yo ranvèse Atik yo sou yon 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);
Collections.reverse(fruitBasket);
System.out.println(fruitBasket); } }

Sòti:

#original list [Apple, Banana, Grapes, Orange] #after reverse [Orange, Grapes, Banana, Apple]

Ki jan yo konvèti yon ArrayList Array

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);
} } }

Sòti:

Apple Banana Grapes Orange

Kouman Swap De Atik nan yon 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(fruitBasket1);
Collections.swap(fruitBasket, 1, 3);
System.out.println(fruitBasket); } }

Sòti:

#before swap [Apple, Banana, Grapes, Orange] #after swap [Apple, Orange, Grapes, Banana]

Ki jan yo rantre nan De ArrayLists

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); } }

Sòti:

[Apple, Banana, Grapes, Orange, Melon, Strawberries]

Konklizyon

Nan pòs sa a ou te wè egzanp diferan nan operasyon ki pi komen sou Java ArrayLists.