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    <p>The following snippet gives an example that shows how to get an element from a <code>List</code> at a specified index, and also how to use the advanced for-each loop to iterate through all elements:</p> <pre><code> import java.util.*; //... List&lt;String&gt; list = new ArrayList&lt;String&gt;(); list.add("Hello!"); list.add("How are you?"); System.out.println(list.get(0)); // prints "Hello!" for (String s : list) { System.out.println(s); } // prints "Hello!", "How are you?" </code></pre> <p>Note the following:</p> <ul> <li>Generic <code>List&lt;String&gt;</code> and <code>ArrayList&lt;String&gt;</code> types are used instead of raw <code>ArrayList</code> type.</li> <li>Variable names starts with lowercase</li> <li><code>list</code> is declared as <code>List&lt;String&gt;</code>, i.e. the interface type instead of implementation type <code>ArrayList&lt;String&gt;</code>.</li> </ul> <hr> <h2>References</h2> <h3>API:</h3> <ul> <li><a href="http://java.sun.com/docs/books/tutorial/collections/index.html" rel="noreferrer">Java Collections Framework tutorial</a></li> <li><a href="http://java.sun.com/javase/6/docs/api/java/util/ArrayList.html" rel="noreferrer"><code>class ArrayList&lt;E&gt; implements List&lt;E&gt;</code></a></li> <li><a href="http://java.sun.com/javase/6/docs/api/java/util/List.html" rel="noreferrer"><code>interface List&lt;E&gt;</code></a> <ul> <li><a href="http://java.sun.com/javase/6/docs/api/java/util/List.html#get%28int%29" rel="noreferrer"><code>E get(int index)</code></a> <ul> <li>Returns the element at the specified position in this list.</li> </ul></li> </ul></li> </ul> <h3>Don't use raw types</h3> <ul> <li><p><a href="http://java.sun.com/docs/books/jls/third_edition/html/typesValues.html#4.8" rel="noreferrer">JLS 4.8 Raw Types</a></p> <blockquote> <p>The use of raw types is allowed only as a concession to compatibility of legacy code. The use of raw types in code written after the introduction of genericity into the Java programming language is strongly discouraged. <em>It is possible that future versions of the Java programming language will disallow the use of raw types.</em></p> </blockquote></li> <li><p><em>Effective Java 2nd Edition: Item 23: Don't use raw types in new code</em></p> <blockquote> <p><em>If you use raw types, you lose all the safety and expressiveness benefits of generics.</em></p> </blockquote></li> </ul> <h3>Prefer interfaces to implementation classes in type declarations</h3> <ul> <li><em>Effective Java 2nd Edition: Item 52: Refer to objects by their interfaces</em> <blockquote> <p>[...] you should favor the use of interfaces rather than classes to refer to objects. <em>If appropriate interface types exist, then parameters, return values, variables, and fields should all be declared using interface types</em>.</p> </blockquote></li> </ul> <h3><a href="http://java.sun.com/docs/codeconv/html/CodeConventions.doc8.html" rel="noreferrer">Naming conventions</a></h3> <blockquote> <p>Variables: Except for variables, all instance, class, and class constants are in mixed case with a <em>lowercase first letter</em>.</p> </blockquote>
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