Answers for "how to know the type in java"

get type of variable java

((Object) myVar).getClass().getName()
//OR
((Object) myInt).getClass().getSimpleName()

java typeof

Object obj = null;
obj = new ArrayList<String>();
System.out.println(obj.getClass());

obj = "dummy";
System.out.println(obj.getClass());

obj = 4;
System.out.println(obj.getClass());