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    <p>You can only access protected members of a type in a different package if the compile-time type of the expression you're referencing it through is either your own class or a subclass. (Where "your" class is the class containing the code.) Your own class has to be a subclass of the type which originally declares the method, too.</p> <p>Here's an example; assume that <code>Base</code> is in a different package to all the other classes:</p> <pre><code>package first; public class Base { protected void Foo() {} } // Yes, each class is really in its own file normally - but treat // all the classes below as being in package "second" package second; public class Child extends Base { public void OtherMethod(Object x) { ((Base) x).Foo(); // Invalid: Base is not Child or subclass ((Child) x).Foo(); // Valid: Child is Child ((GrandChild) x).Foo(); // Valid: GrandChild is subclass of Child ((OtherChild) x).Foo(); // Invalid: OtherChild is not Child or subclass } } public class GrandChild extends Child {} public class OtherChild extends Base {} </code></pre> <p>In other words, it's letting you have access to the protected members of "objects which are a like you".</p> <p>Details are in <a href="http://java.sun.com/docs/books/jls/third_edition/html/names.html#6.6.2" rel="noreferrer">section 6.6.2 of the Java Language Specification</a>:</p> <blockquote> <p>A <code>protected</code> member or constructor of an object may be accessed from outside the package in which it is declared only by code that is responsible for the implementation of that object.</p> <p><strong>6.6.2.1 Access to a protected Member</strong></p> <p>Let <em>C</em> be the class in which a protected member <em>m</em> is declared. Access is permitted only within the body of a subclass <em>S</em> of <em>C</em>. In addition, if Id denotes an instance field or instance method, then: If the access is by a qualified name <em>Q.Id</em>, where <em>Q</em> is an <em>ExpressionName</em>, then the access is permitted if and only if the type of the expression <em>Q</em> is <em>S</em> or a subclass of <em>S</em>. If the access is by a field access expression <em>E.Id</em>, where <em>E</em> is a <em>Primary</em> expression, or by a method invocation expression <em>E.Id(. . .)</em>, where <em>E</em> is a <em>Primary</em> expression, then the access is permitted if and only if the type of <em>E</em> is <em>S</em> or a subclass of <em>S</em>.</p> </blockquote>
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    1. POHow are java.lang.Object's protected methods protected from subclasses?
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    1. USJon Skeet
    1. USJon Skeet
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    1. POHow are java.lang.Object's protected methods protected from subclasses?
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    1. CONote from that reference that classes can access protected members of _any_ class in the same package.
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      1. USMichael Myers
    2. COYou have a typo: <pre> public class Child extends Base {} { […] } </pre>
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      1. USAdrian Heine
    3. COWhoops, thanks both - will fix.
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