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    <blockquote> <ul> <li>Now the question is does serialization loads the class again to have two instance of Elvis?</li> </ul> </blockquote> <p>A new instance of Elvis is created (the impersonator), but the overloaded <code>readResolve</code> method ensures that it is not returned as part of the data structure returned by <code>ObjectInputStream.readObject()</code>.</p> <p>The Elvis impersonator is (or soon becomes) unreachable, and is garbage collected.</p> <blockquote> <ul> <li>If the class is loaded only once then we should be having only one instance of Elvis since static fields are not serialized and are not restored during deserialization and</li> </ul> </blockquote> <p>Ideally yes. In practice no.</p> <blockquote> <ul> <li>From where does the other Elvis instance comes which is made eligible for garbage collection by readResolve (prevented from escaping the deserialization process). Can this be explained?</li> </ul> </blockquote> <p>The deserialization process starts out by creating the 2nd Elvis (the impersonator), but the <code>readResolve</code> method ensures that nothing ever sees it. </p> <p>To understand how and why that is the case, you need to understand the function that a <code>readResolve()</code> method plays in deserialization, as specified <a href="http://download.oracle.com/javase/6/docs/platform/serialization/spec/input.html#5903" rel="nofollow">here</a>. Basically, when the <code>readResolve()</code> method returns <code>INSTANCE</code> it is saying, "wherever you were going to use the impersonator in the graph we are building, use the real Elvis instead".</p>
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    1. POEffective Java Item #77 - Serialization of singleton objects - Why should I have to use readResolve?
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    1. USStephen C
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    1. CO@Stephen C The Elvis impersonator becomes unreachable, unless an adversary grabs a reference to it first.
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      1. USTom Hawtin - tackline
    2. CO@Stephen C - "The deserialization process starts out by creating the 2nd Elvis (the impersonator)" - Does it create another object and assign a new value for the static field INSTANCE? Static fields are not serialized and they are initialized when loading the class loads I guess.
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    3. CO@Tom - I thought that's what I said.
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      1. USStephen C
 

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