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copied!<p>To test if two objects are identical (that is: whether they're one and the same), use <code>==</code>, not <code>equals()</code>. With the sample input in the question this would print <code>true</code> and <code>false</code>, <em>assuming</em> that you have implemented <code>equals()</code>:</p> <pre><code>System.out.println(obj1.equals(obj2)); // true System.out.println(obj1 == obj2); // false </code></pre> <p>Or perhaps more interesting:</p> <pre><code>Test obj1 = new Test(100, 22); Test obj2 = new Test(100, 22); Test obj3 = obj2; System.out.println(obj1.equals(obj2)); // true System.out.println(obj1 == obj2); // false System.out.println(obj2 == obj3); // true System.out.println(obj1.equals(obj3)); // true </code></pre> <p>Now back to your question. The problem lies in the fact that you haven't properly implemented <code>equals()</code>, which tests for value <em>equality</em> between objects, and that's what you're interested in. For the code in the question, a correct implementation of <code>equals()</code> would look like this:</p> <pre><code>@Override public boolean equals(Object obj) { if (this == obj) // are the objects identical? return true; if (obj == null) // is the other object null? return false; if (getClass() != obj.getClass()) // do the objects have the same class? return false; Test other = (Test) obj; // cast other object if (a != other.a) // is the `a` field equal in both objects? return false; if (b != other.b) // is the `b` field equal in both objects? return false; return true; // ok, the objects are equal :) } </code></pre>

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