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copied!<p><strong>Update:</strong> My previous answer was wrong. You cannot do it without modifying the default behaviour! See below why. </p> <hr> <blockquote> <p><strong>..how to get the last entry or key entered?</strong></p> </blockquote> <p>From the API description of <code>LinkedHashMap</code> you can read:</p> <blockquote> <p>A structural modification is any operation that adds or deletes one or more mappings or, in the case of access-ordered linked hash maps, affects iteration order. In <strong><em>insertion-ordered</strong> linked hash maps, merely changing the value associated with a key that is already contained in the map is not a structural modification</em>. In <strong><em>access-ordered</strong> linked hash maps, merely querying the map with get is a structural modification</em>.</p> </blockquote> <p>So what does it all mean?</p> <ul> <li><em><strong>access-ordered</em></strong> - every time you do a <code>put</code> or a <code>get</code> the order of the elements changes</li> <li><em><strong>insertion-ordered</em></strong> - when inserting elements (for the first time) they are added last</li> </ul> <p>For example:</p> <pre><code>map.put(1, 1); map.put(2, 2); map.put(1, 10); System.out.println(map); </code></pre> <p>... will print <code>{1=10, 2=2}</code> with <em>insertion-ordered</em> and <code>{2=2, 1=10}</code> with *access-ordered'. The trouble is using <code>access-ordered</code> if of course if you do a <code>get</code> operations the order also changes.</p> <hr> <h2>How to fix</h2> <p>So... how to fix. Well the <code>LinkedHashMap</code> cannot be used directly used. So you can wrap it (do not care about the corny name) and override the <code>put</code> and the <code>putAll</code> methods so that they remove the key from the map first before putting it back in!</p> <pre><code>class BestLinkedHashMap<K, V> extends LinkedHashMap<K, V> { @Override public V put(K key, V value) { V last = super.remove(key); super.put(key, value); return last; } @Override public void putAll(Map<? extends K, ? extends V> m) { for (K key : m.keySet()) super.remove(key); super.putAll(m); } } </code></pre> <hr> <p>Then to get the last element, either do:</p> <ul> <li><p>wrap the output from in a <code>LinkedList</code> implementation:</p> <pre><code>V v = new LinkedList<V>(map.values()).getLast(); </code></pre></li> <li><p><code>toArray()</code> way:</p> <pre><code>Collection<V> values = map.values(); V v = values.toArray(new V[0])[values.size() - 1]; </code></pre></li> <li><p>iterate to the last element using the iterator:</p> <pre><code>Iterator<V> it = values.iterator(); V last = null; while (it.hasNext()) last = it.next(); </code></pre></li> </ul>

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