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    <p>Declaration is not to declare "value" to a variable; it's to declare the <em>type</em> of the variable.</p> <p>Assignment is simply the storing of a value to a variable.</p> <p>Initialization is the assignment of a value to a variable <em>at the time of declaration</em>.</p> <p>These definitions also applies to fields.</p> <pre><code>int i; // simple declaration i = 42 // simple assignment int[] arr = { 1, 2, 3 }; // declaration with initialization, allows special shorthand syntax for arrays arr = { 4, 5, 6 }; // doesn't compile, special initializer syntax invalid here arr = new int[] { 4, 5, 6 }; // simple assignment, compiles fine </code></pre> <hr> <p>However, it should be mentioned that "initialization" also has a more relaxed definition of "the first assignment to a variable", regardless of where it happens.</p> <pre><code>int i; // local variable declaration if (something) i = 42; System.out.println(i); // compile time error: The local variable i may not have been initialized </code></pre> <p>This, however, compiles:</p> <pre><code>int i; // the following also compiles if i were declared final if (something) i = 42; else i = 666; System.out.println(i); </code></pre> <p>Here <code>i</code> can be "initialized" from two possible locations, by simple assignments. Because of that, if <code>i</code> was an array, you can't use the special array initializer shorthand syntax with this construct.</p> <p>So basically "initialization" has two possible definitions, depending on context:</p> <ul> <li>In its narrowest form, it's when an assignment is comboed with declaration. <ul> <li>It allows, among other things, special array shorthand initializer syntax</li> </ul></li> <li>More generally, it's when an assignment is first made to a variable. <ul> <li>It allows, among other things, assignments to a <code>final</code> variable at multiple places. <ul> <li>The compiler would do its best to ensure that exactly one of those assignments can happen, thus "initializing" the <code>final</code> variable</li> </ul></li> </ul></li> </ul> <hr> <p>There's also JVM-context class and instance initialization, OOP-context object initialization, etc.</p>
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    1. POJava: define terms initialization, declaration and assignment
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    1. CO"int[] arr = { 1, 2, 3 };" is arr-declared and {1,2,3}-assignment. It implies an initialization. Right?
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    2. COYes, that is an example of the special array initializer syntax being used, so it is initialization.
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