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The @Override Annontation in J2SE5.0
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Override/Overload Annotation-J2SE5.0 Java Security Class Loading Class Verifier SecurityManager |
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One of the annotations available with the addition of the metadata facility in Java Version 5.0 (see Chapter 1: Java and Chapter 1 Java: Supplement), greatly reduces the chance of accidentally overloading when you really want to override. The @Override annotation tells the compiler that you intend to override a method from a superclass. If you don't get the parameter list quite right so that you're really overloading the method name, the compiler emits a compile-time error. This annotation is used as follows
The metadata facility in Java 5.0 supports simple and complex annotation types, which are closely related to Java interfaces. Some annotation types define member methods and member variables and require parameters when used. However, the @Override annotation is just a marker interface. It has no members, and thus accepts no parameters when used, as shown above. It must appear on a line by itself and indicates that the method name on the next line should override a method from a superclass. If the method signature on the next line isn't really an overriding signature, then the compiler complains as follows Parent.java:10:
method does not override a method from its superclass By using @Override each time you intend to override a method from a superclass, you are safe from accidentally overloading instead of overriding. References & Web Resources
Latest update: Oct. 20, 2004 |
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