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copied!<p>Look here:</p> <pre><code>public boolean equals(Object other) { if (this.getClass().isInstance(other)) { return true; } else { return false; } } </code></pre> <p>Your <code>equals()</code> method is definitely broken. This returns <code>true</code> for <strong>every</strong> other <code>User</code> object, even though it internally holds a completely different user ID/name. So the selected item matches <strong>every</strong> available select item value. That's why you see the last item being preselected everytime.</p> <p>Assuming that the <code>id</code> property is unique for every user, then the <code>equals()</code> method should at its simplest rather look like this:</p> <pre><code>public boolean equals(Object other) { if (!(other instanceof User)) { return false; } if (other == this) { return true; } if (id != null) { return id.equals(((User) other).id); } return false; } </code></pre> <p>which can also be summarized as follows</p> <pre><code>public boolean equals(Object other) { return (other instanceof User) && (id != null) ? id.equals(((User) other).id) : (other == this); } </code></pre> <p>Hint: a bit decent IDE like Eclipse can autogenerate <code>equals()</code> (and <code>hashCode()</code>) method.</p> <h3>See also:</h3> <ul> <li><a href="https://stackoverflow.com/questions/3181339/right-way-to-implement-equals-contract">Right way to implement equals contract</a></li> <li><a href="https://stackoverflow.com/questions/4417035/generic-reflective-helper-method-for-equals-and-hashcode/4417048#4417048">Generic reflective helper method for equals and hashCode</a></li> </ul>

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