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    <p>What you're seeing is because you're using <code>String</code>, which has a very special (and <em>nearly</em> unique) behavior: Your two strings are actually one <code>String</code> object, because string literals are automatically <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#intern%28%29" rel="noreferrer"><code>intern</code>'d</a>. The JDK and JVM work together to put string literals into a pool of <code>String</code> instances which are reused, rather than creating separate <code>String</code> instances for the same sequence of characters.</p> <p>Try your experiment with <code>new Object()</code> instead:</p> <pre><code> Object a = new Object(); Object b = new Object(); System.out.println(a.hashCode()); System.out.println(b.hashCode()); System.out.println(System.identityHashCode(a)); System.out.println(System.identityHashCode(b)); </code></pre> <hr> <blockquote> <p>Also what is difference between hashcode() and system.identityhashcode()</p> </blockquote> <p>The <code>hashCode</code> function can be overridden by a class to return something appropriate for that class. <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/System.html#identityHashCode%28java.lang.Object%29" rel="noreferrer"><code>System.identityHashCode</code></a> returns the same <code>hashCode</code> that <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html#hashCode%28%29" rel="noreferrer"><code>Object#hashCode</code></a> <em>would</em> have returned if the subclass hadn't overridden it.</p> <p>So for <code>Object</code>, you'd get the same return value from each of them. But for any class that overrides <code>hashCode</code> to return something more appropriate for that class (which includes <code>String</code>), you'd get different values.</p>
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    1. POHow every object are different from one another
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    1. UST.J. Crowder
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    1. POHow every object are different from one another
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    1. COAdding to @TJ's answer, even `new String("Hello");` would show the difference in `identityHashCode`!
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    2. CO@R.J: True, but I didn't want to introduce even more confusion. :-)
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    3. CO+1 I would also add that `new String()` means `create new object on heap/return new object` and `String a="text"` means `use existing object from heap/string pool.`
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