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    <p>Let us walk through the JVM:</p> <pre><code>B b1 = new B(){ int m(A a,A b) { return 10; } }; </code></pre> <p>This creates an instance of <code>B</code> with an anonymous overload of method <code>m()</code> having two arguments of type <code>A</code>. But this is a <em>different</em> <code>m()</code> method than what class <code>B</code> (or <code>A</code>) defines, since their <em>signature</em> (<code>A, A</code> vs <code>A, B</code>) differ.</p> <p>Then:</p> <pre><code>System.out.println(b1.m(b1, b1)); </code></pre> <p>This calls <code>b1</code>'s <code>m()</code> method with two arguments of type <code>B</code>.</p> <p>Now the JVM looks up what <code>m()</code> is:</p> <ul> <li>there is no method <code>m()</code> having two arguments of type <code>B</code>;</li> <li>in class <code>B</code>, it finds a match: a method by name <code>m()</code> whose first argument is a <code>A</code> (since <code>B</code> inherits <code>A</code>) and a second argument which is of type <code>B</code>;</li> <li><strong>the anonymous overloading by <code>b1</code> is <em>completely ignored</em> here!</strong> (see <a href="https://gist.github.com/fge/5762353" rel="nofollow">https://gist.github.com/fge/5762353</a>)</li> <li>end of method lookup.</li> </ul> <p>The <code>m()</code> method of class <code>B</code> is therefore invoked. And in this method, we have:</p> <pre><code>if (a1 == a2) // TRUE! return x; </code></pre> <p>Since the condition is true (the method has been called with the two arguments being the exact same object references), the value of <code>x</code> must be returned; and <code>x</code> is defined by class <code>A</code>, which class <code>B</code> <code>extends</code>:</p> <pre><code> public static int x = 1; </code></pre> <p>Since this is a <strong>static</strong> member of class A (which class B does not hide) it is equally accessible by instance methods, from any instance of <code>A</code> or <code>B</code>; therefore, the return code, and output of this program, is 1.</p>
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    1. COIt isn't looking at the method defined within the anonymous inner class because the (static) type of `b1` is `B`.
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    2. CONo. Try the sample code with the anonymous overload of `m()` having two arguments of type `B` instead of `A`: the returned value will be 10! Because `B,B` is more specific that `A, B`; but here, the overload is `A, A` which is _less_ specific.
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    3. COIf it does that, I think there's a bug in javac. (I don't have Java installed on my own machine.)
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