lists in java code example
Example 1: Lists inside lists in java
public class GuiTest {
public static void main(String[] args) {
List<List<Integer>> MainList = new ArrayList<List<Integer>>();
Random NewRandomNumber = new Random();
for (int i = 0; i < 10; i++) {
List<Integer> SecondList = new ArrayList<Integer>();
MainList.add(SecondList);
for (int i2 = 0; i2 < 10; i2++) {
SecondList.add(NewRandomNumber.nextInt(6));
}
}
Example 2: list in java
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.ListIterator;
public class Main {
public static void main(String[] args) {
List<String> list = new ArrayList<String>();
list.add("a");
list.add("b");
list.add("c");
list.add("d");
list.add("e");
list.add("f");
//On met la liste dans le désordre
Collections.shuffle(list);
System.out.println(list);
//On la remet dans l'ordre
Collections.sort(list);
System.out.println(list);
Collections.rotate(list, -1);
System.out.println(list);
//On récupère une sous-liste
List<String> sub = list.subList(2, 5);
System.out.println(sub);
Collections.reverse(sub);
System.out.println(sub);
//On récupère un ListIterator
ListIterator<String> it = list.listIterator();
while(it.hasNext()){
String str = it.next();
if(str.equals("d"))
it.set("z");
}
while(it.hasPrevious())
System.out.print(it.previous());
}
}
Example 3: java list
import java.util.*;
var list = new ArrayList<String>();
list.add("Hello World!");
Example 4: list in java
LIST: Can store duplicate values,
Keeps the insertion order.
It allows multiple null values,
Also we can read a certain value by index.
- ArrayList not syncronized, array based class
- LinkedList not synchronized, doubly linked
- Vector is synchronized, thread safe
Example 5: declaration of list in java
ArrayList<String> list=new ArrayList<String>();//Creating arraylist
list.add("Mango");//Adding object in arraylist
list.add("Apple");
list.add("Banana");
list.add("Grapes");
//Printing the arraylist object
System.out.println(list);
Example 6: java list of objects example
List<Object> listAnything = new ArrayList<Object>();
List<String> listWords = new ArrayList<String>();
List<Integer> listNumbers = new ArrayList<Integer>();
List<String> linkedWords = new LinkedList<String>();