Java Glossary : ClassCastException

Java definitions: 0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

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ClassCastException

You can cast null into anything without raising a ClassCastException. Generally, this is a good thing. Otherwise every cast would need an if to specially handle the null case. You might be tempted to count on ClassCastExceptions to filter out nulls for you. The following code will not raise a java.lang.ClassCastException:

Cat c = null;
Object o = c;
Dalmatian d = (Dalmatian)o;

In other words, there is one universal representation for null, not a special one for each class. For more detail

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