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<b>Trail:</b> Learning the Java Language

<br /><b>Lesson:</b> Interfaces and Inheritance

<br /><b>Section:</b> Interfaces

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<div id="PageTitle"><h1>Summary of Interfaces</h1></div>

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<p>An interface declaration can contain method signatures, default methods, static methods and constant definitions. The only methods that have implementations are default and static methods.</p>

<p>A class that implements an interface must implement all the methods declared in the interface.</p>

<p>An interface name can be used anywhere a type can be used.</p>

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