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copied!<p>The issue here is that <a href="http://java.sun.com/javase/6/docs/api/java/util/Map.html" rel="noreferrer"><code>Map</code></a> has two values (a key and value), while a <a href="http://java.sun.com/javase/6/docs/api/java/util/List.html" rel="noreferrer"><code>List</code></a> only has one value (an element).</p> <p>Therefore, the best that can be done is to either get a <code>List</code> of the keys or the values. (Unless we make a wrapper to hold on to the key/value pair).</p> <p>Say we have a <code>Map</code>:</p> <pre><code>Map<String, String> m = new HashMap<String, String>(); m.put("Hello", "World"); m.put("Apple", "3.14"); m.put("Another", "Element"); </code></pre> <p>The keys as a <code>List</code> can be obtained by creating a new <a href="http://java.sun.com/javase/6/docs/api/java/util/ArrayList.html" rel="noreferrer"><code>ArrayList</code></a> from a <a href="http://java.sun.com/javase/6/docs/api/java/util/Set.html" rel="noreferrer"><code>Set</code></a> returned by the <a href="http://java.sun.com/javase/6/docs/api/java/util/Map.html#keySet()" rel="noreferrer"><code>Map.keySet</code></a> method:</p> <pre><code>List<String> list = new ArrayList<String>(m.keySet()); </code></pre> <p>While the values as a <code>List</code> can be obtained creating a new <code>ArrayList</code> from a <a href="http://java.sun.com/javase/6/docs/api/java/util/Collection.html" rel="noreferrer"><code>Collection</code></a> returned by the <a href="http://java.sun.com/javase/6/docs/api/java/util/Map.html#values()" rel="noreferrer"><code>Map.values</code></a> method:</p> <pre><code>List<String> list = new ArrayList<String>(m.values()); </code></pre> <p>The result of getting the <code>List</code> of keys:</p> <pre> Apple Another Hello </pre> <p>The result of getting the <code>List</code> of values:</p> <pre> 3.14 Element World </pre>

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