How to store a default values in a List for a specific size

We can store a default values to the List interfcae implementation classes like ArrayList, LinkedList etc .
The storing a specific default value to the specific size of the array List implementation class is possible, Please check the below code for it.

Storing Integer values 0 as default value to the ArrayList of size 100;

      Integer intArray[] = new Integer[100];
      List al = new ArrayList(Arrays.asList(intArray));
      Collections.fill(al,0);
      System.out.println("ArrayList values are :"+al);

Storing String values "zameer" as default value to the ArrayList of size 100;

      String stArray[] = new String[100];
      List al = new ArrayList(Arrays.asList(stArray));
      Collections.fill(al,"zameer");
      System.out.println("ArrayList values are :"+al);

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How to know the data type of the elements from the list of collection objects in java

To know the data types from the list of collection objects in java is by using the below code


public class CheckDataTypes{

      pubic static void main(String[] args){
   
   List
list.add(10);
list.add("hello");
list.add('a');
list.add(34.4);
list.add(22.3f);
for(Object obj:list){
if(obj.getClass().equals(String.class)){
System.out.println(" String type");
}else if(obj.getClass().equals(Integer.class)){
System.out.println("Integer type");
}else if(obj.getClass().equals(Float.class)){
System.out.println("Float type ");
}else if(obj.getClass().equals(Double.class)){
System.out.println("Double type ");
}else if(obj.getClass().equals(Character.class)){
System.out.println("Char Type");
}
}
      }//Main method closed

}// class ended



One more way is : 


public class DataType {
   public static void main(String args[]){
     
  List
list.add(10);
list.add("hello");
list.add('a');
list.add(34.4);
list.add(22.3f);
for(Object obj:list){
if(obj instanceof String){
System.out.println(" String type");
}else if(obj instanceof Integer){
System.out.println("Integer type");
}else if(obj instanceof  Float){
System.out.println("Float type ");
}else if(obj instanceof  Double){
System.out.println("Double type ");
}else if(obj instanceof Character){
System.out.println("Char Type");
}
    }//for each loop closed
   }//main method closed
}//Class is closed