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    <p>These initializations are done when the new instance of the class is created by JVM . See <a href="http://docs.oracle.com/javase/specs/jls/se7/html/jls-12.html#jls-12.5" rel="nofollow">Creation of new class instances</a> section . It states:</p> <blockquote> <p>Whenever a new class instance is created, memory space is allocated for it with room for all the instance variables declared in the class type and all the instance variables declared in each superclass of the class type, including all the instance variables that may be hidden (§8.3).</p> <p>If there is not sufficient space available to allocate memory for the object, then creation of the class instance completes abruptly with an OutOfMemoryError. Otherwise, <strong>all the instance variables in the new object, including those declared in superclasses, are initialized to their default values</strong> (§4.12.5).</p> </blockquote> <p>The default value is as follows for each type of instance variable:</p> <blockquote> <ul> <li>For type <code>byte</code>, the default value is zero, that is, the value of <code>(byte)0</code>.</li> <li>For type <code>short</code>, the default value is zero, that is, the value of <code>(short)0</code>.</li> <li>For type <code>int</code>, the default value is zero, that is, <code>0</code>.</li> <li>For type <code>long</code>, the default value is zero, that is, <code>0L</code>.</li> <li>For type <code>float</code>, the default value is positive zero, that is, <code>0.0f</code>.</li> <li>For type <code>double</code>, the default value is positive zero, that is, <code>0.0d</code>.</li> <li>For type <code>char</code>, the default value is the null character, that is, <code>'\u0000'</code>.</li> <li>For type <code>boolean</code>, the default value is <code>false</code>.</li> <li>For all <code>reference types</code> (§4.3), the default value is <code>null</code>.</li> </ul> </blockquote>
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    1. POWhich mechanism is responsible for initial initialiazation of fields in Java
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    1. USVishal K
    1. USVishal K
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    1. COSo it seems that its `new` keyword that makes JVM try to create new object of selected class by allocating space required for that object (and its superclass, and its superclass, and so on until Object) and *setting values of fields to "zeros"*. Then initialization to "correct" values occurs in constructor. Did I misunderstood something?
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      1. USPshemo
    2. CO@Pshemo Keyword `new` is one the ways of creating an object. It is the creation of object that makes JVM to allocate space required and setting the values of fields to `default`. And yes you are correct in your words that : then initialization to assigned value occurs in `constructor` or within `instance initializer`.
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      1. USVishal K
    3. CO@Pshemo Thank you. It seems thatbCONSTRUCTOR!!! is doing that.
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      1. USangry_gopher
 

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