Beste svaret
import java.util.ArrayList;
import org.testng.annotations.Test;
public class arrayList {
@Test
public void arrayListTest() {
// Define array list which can hold array list objects
// of type any (String/Integer/Boolean)
ArrayList
// Define array list 1 and add data to it
ArrayList
innerInt1.add(100);
innerInt1.add(300);
innerInt1.add(500);
// Define array list 2 and add data to it
ArrayList
innerInt2.add(200);
innerInt2.add(400);
innerInt2.add(600);
// Add inner array list objects created to outer array list
// Outer array declaration says it can hold
// arraylist objects of type Integer
outer.add(innerInt1); // here innerInt1 is ArrayList Object
outer.add(innerInt2); // here innerInt2 is ArrayList Object
// Print using prinln function
System.out.println(outer);
// Pring using for loop dynamically
for(int i=0;i
for(int j=0;j
System.out.println(outer.get(i).get(j));
}
}
}
}
Utgang :
[[100, 300, 500], [200, 400, 600]]
100300500200400600
PASSED: arrayListTest == ================================================ Standard testtester kjøres: 1, feil: 0, hopper over: 0 ============================================= ==== Standard suite Totalt antall test: 1, Feil: 0, Hopp over: 0 =================================== ================
Svar
Vi kan vise alle elementene i ArrayList i Java ved hjelp av:
- Ved bruk av for loop
- Ved bruk av forbedret for loop
- Ved bruk av lambdauttrykk
- Ved bruk av metodehenvisning
- Ved bruk av strøm
La oss se i eksempel:
import java.util.ArrayList;
import java.util.Arrays;
public class MainClass
{
public static void main(String[] arg)
{
ArrayList
// Display all the elements in ArrayList in Java using for loop?
System.out.println("By use of for loop");
for(int i = 0; i < list.size(); i++)
{
System.out.println(list.get(i));
}
// Display all the elements in ArrayList in Java using enhanced for loop?
System.out.println("By use of enhanced for loop");
for(Integer ele : list)
{
System.out.println(ele);
}
// Display all the elements in ArrayList in Java using forEach loop
// Using lambda expression
System.out.println("By use of lambda expression");
list.forEach(a -> System.out.println(a));
// Display all the elements in ArrayList in Java using forEach loop
// Using method reference
System.out.println("By use of method reference");
list.forEach(System.out::println);
// Display all the elements in ArrayList in Java using forEach loop with Streams
System.out.println("By use of stream");
list.stream().forEach(ele -> System.out.println(ele));
}
}