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Questions tagged [classcastexception]

The Java exception thrown to indicate that the code has attempted to cast an object to a subclass of which it is not an instance.

ClassCastException is the Java unchecked exception thrown to indicate that the code has attempted to cast an object to a subclass of which it is not an instance.

FAQ:

  1. Explanation of "ClassCastException" in Java
  2. What else can throw a ClassCastException in java?
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explicit casting from super class to subclass

public class Animal { public void eat() {} } public class Dog extends Animal { public void eat() {} public void main(String[] args) { Animal animal = new Animal(); Dog dog = (Dog) animal; } } The assignment Dog dog…
saravanan
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java: (String[])List.toArray() gives ClassCastException

The following code (run in android) always gives me a ClassCastException in the 3rd line: final String[] v1 = i18nCategory.translation.get(id); final ArrayList v2 = new ArrayList(Arrays.asList(v1)); String[] v3 =…
Gavriel
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Explanation of ClassCastException in Java

I read some articles written on "ClassCastException", but I couldn't get a good idea on what it means. What is a ClassCastException?
Chathuranga Chandrasekara
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What else can throw a ClassCastException in java?

This is an interview question. The interview is over, but this question is still on my mind. I can't ask the interviewer, as I did not get the job. Scenario: put object of class C1 in to a cache with key "a" Later code: C1 c1FromCache = (C1)…
tgkprog
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ClassCastException when casting to the same class

I have 2 different Java projects, one has 2 classes: dynamicbeans.DynamicBean2 and dynamic.Validator. On the other project, I load both of these classes dynamically and store them on an Object class Form { Class beanClass; Class…
Jaime Garcia
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Why am I getting a ClassCastException when generating javadocs?

I'm using ant to generate javadocs, but get this exception over and over - why? I'm using JDK version 1.6.0_06. [javadoc] java.lang.ClassCastException: com.sun.tools.javadoc.ClassDocImpl cannot be cast to com.sun.javadoc.AnnotationTypeDoc …
ScArcher2
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ClassCastException, casting Integer to Double

ArrayList marks = new ArrayList(); Double sum = 0.0; sum = ((Double)marks.get(i)); Everytime I try to run my program, I get a ClassCastException that states: java.lang.Integer cannot be cast to java.lang.Double
Khuba
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Android: ClassCastException when adding a header view to ExpandableListView

I'm trying to add a header to an ExpandableListView like so: headerView = View.inflate(this, R.layout.header, null); expandableListView.addHeaderView(headerView); expandableListView.setAdapter(new SectionedAdapter(this)); Which gives me the…
Christopher Perry
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android.app.Application cannot be cast to android.app.Activity

I'm trying to change a LinearLayout from another class, but when i run this code: public class IRC extends PircBot { ArrayList channels; ArrayList userCount; ArrayList topics; LinearLayout channelLayout; Context…
DomeWTF
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can't cast to implemented interface

i'm very confused... I have a class which directly implements an interface: public class Device implements AutocompleteResult {...} Here is proof that I'm looking at the right variables: Object match = ...; log.debug(match.getClass()); // Outputs…
pstanton
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ClassCastException: RestTemplate returning List instead of List

I'm trying to access getter methods on my MyModelClass but my code is returning List instead of List. This is my code. List myModelClass=(List)…
Erick
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How does one declare the type of an Android preference?

I have a preferences.xml that looks like this:
David R.
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Casting Java functional interfaces

As always I was looking through JDK 8 sources and found very interesting code: @Override default void forEachRemaining(Consumer action) { if (action instanceof IntConsumer) { forEachRemaining((IntConsumer) action); }…
Andrii Abramov
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Getting class cast exception where both classes are exactly the same

I am doing a JBoss SEAM project and when I view a form I get this error. java.lang.ClassCastException: it.cogitoweb.csi.entity.csiorelav.CsiTipoLav cannot be cast to it.cogitoweb.csi.entity.csiorelav.CsiTipoLav Its alway the same JPA class which is…
Phil
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java.lang.ClassCastException: com.sun.faces.facelets.compiler.UIInstructions cannot be cast to org.primefaces.model.menu.MenuElement

This morning I came in to my office and the first thing I saw: my company site crashed. Because of me I think. Now I tried for one hour and a half to fix this, but I found nothing and everybody looses their mind because the website doesn't work and…
user1713847
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