when to use which list in java code example
Example 1: 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");
Collections.shuffle(list);
System.out.println(list);
Collections.sort(list);
System.out.println(list);
Collections.rotate(list, -1);
System.out.println(list);
List<String> sub = list.subList(2, 5);
System.out.println(sub);
Collections.reverse(sub);
System.out.println(sub);
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 2: 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 3: java list
import java.util.*;
var list = new ArrayList<Foo>();
list.add(new Foo());