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getClass().getName() returns null


getClass().getName() returns null

By : user2953204
Date : November 20 2020, 01:01 AM
I wish did fix the issue. Skip the lazy initialization in initName! It is not thread-safe.
Instead, initialize the ThreadLocal field directly (and also note the final):
code :
private static final ThreadLocal<String> className = new ThreadLocal<>();


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Java getClass().getName() it returns the class not the name

Java getClass().getName() it returns the class not the name


By : Mohita Sharma
Date : March 29 2020, 07:55 AM
will be helpful for those in need getClass() returns the Class object representing the "Card" class; therefore the code does not refer to Card#getName method, but rather to Class#getName which dutifully returns "Card".
Simply remove getClass():
code :
public String toString()
{
    return getName();
}
nullPointerException, guess when using getClass().getName()

nullPointerException, guess when using getClass().getName()


By : Sumit
Date : March 29 2020, 07:55 AM
it helps some times If your comment about where the exception occurs is correct, then method is null. You should verify this by using a debugger to step to that piece of code and inspect the statement. Alternatively, add Sysouts for all involved variables.
If this is unexpected, say you're convinced that methodis set by some other part of your code, add a breakpoint or output to that other part to verify that it's actually doing what you think it's doing, and in the correct order, too.
In Java, assuming we have a class called Foo, how does obj.getClass().getName() and Foo.class.getName() fetch same resul

In Java, assuming we have a class called Foo, how does obj.getClass().getName() and Foo.class.getName() fetch same resul


By : futureorbit
Date : March 29 2020, 07:55 AM
To fix this issue Foo.class is a static instance of type Class; there is only one such instance at runtime.*
If obj is of type Foo, then obj.getClass() returns Foo.class, by definition.
How to do object.getClass().getName() in Java

How to do object.getClass().getName() in Java


By : S.jana
Date : March 29 2020, 07:55 AM
wish help you to fix your issue Looks like you are practicing some OO with Java . It's better if you ask a doubt instead the full scenario.
However I will paste a sample here and you can ask any doubt you have. FoodFactory class below, note that for a name you will get the right Object.
code :
public class FoodFactory {

  public Food getFood(String food) {

    if ("Meat".equals(food)) {
      return new Meat();
    } else if ("Fruit".equals(food)) {
      return new Fruit();
    }
    throw new IllegalArgumentException("No food found with name " + food);
  }
}
public class Meat extends Food {
}
public class Food {
  public void serveFood() {
    System.out.println("I'm serving " + getClass().getSimpleName());
  }
}
FoodFactory ff = new FoodFactory();
Food f1 = ff.getFood("Fruit");
Food f2 = ff.getFood("Meat");
f1.serveFood();
f2.serveFood();
System.out.println(f1.getClass().getSuperclass().getSimpleName());
System.out.println(f1.getClass().getSimpleName());
System.out.println(f2.getClass().getSimpleName());
Using getClass().getName() in toString() methods

Using getClass().getName() in toString() methods


By : bored_panda
Date : March 29 2020, 07:55 AM
around this issue getClass() is a polymorphic method. It returns the actual concrete class of the object on which it is called. Since d id of type DerivedClass, its getClass() method returns DerivedClass.class.
You would get the result you expect if the method implementation was
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