Im trying to make a list of objects and print them out in java. I get error in multiple places.

Question

import java.util.* ;
class Animal {
ArrayList<String> animalList = new ArrayList<String>();
String type_of_animal ;
String name ;
int age ;
public Animal(String type_of_animal, String name, int age){

}
public static void main(String[] args) {
Animal lion = new Animal("lion", "Simba", 10);
animalList.add(lion);<----error
for(String a : animalList){
System.out.println(a.type_of_animal, a.name, a.age) ;<---error
}
}
}

Answer 1

Lenoname

You have declared list of String but adding object of Animal class which is wrong

type_of_animal is a field of Animal class not String class so you cannot print like that

your constructor is incomplete

Answer 2

Lenoname

println() method except only one arguments so you have to use seperate println method

You cannot access non-static members in static methods

//like this?(i changed type_of_animal to aType), how can i print out then?

import java.util.*;

class Animal {

String aType;
String name;
int age;

public Animal(String aType, String name, int age) {
this.aType = aType;
this.name = name;
this.age = age;
}

public static void main(String[] args) {
Animal lion = new Animal("lion", "Simba", 10);

List<Animal> animalList = new ArrayList<>();

animalList.add(lion);

for(Animal a : animalList) {
System.out.println(a.aType);
System.out.println(a.name);
System.out.println(a.age);
}
}
}

Answer 3

like this?(i changed type_of_animal to aType), how can i print out then?

import java.util.* ;
class Animal {
ArrayList<Animal> animalList = new ArrayList<>();
String aType ; ;
String name ;
int age ;
public Animal(String aType, String name, int age){
this.aType = aType ;
this.name = name ;
this.age = age ;
}
public static void main(String[] args) {
Animal lion = new Animal("lion", "Simba", 10);
animalList.add(lion);
for(Animal a : animalList){
System.out.println(a.aType, a.name, a.age) ;
}
}
}