Smarter extract to local variable refactoring

- N&N for: eclipse-jdt/eclipse.jdt.ui#66

4.26/jdt.html

@@ -105,6 +105,19 @@ <h2>Java Editor </h2>
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+  <tr id="smarter-extract-local"> <!-- https://github.com/eclipse-jdt/eclipse.jdt.ui/pull/66 -->
+    <td class="title"><a href="#smarter-extract-local">Extract local variable improved</a></td>
+    <td class="content">
+      The extract local variable refactoring available from <b>Refactor -> Extract Local Variable</b> has been improved to recognize
+      situations where adding the local variable may cause a NullPointerException as it precedes code used to check for null.  In these cases, 
+      the positioning of the local variable is altered so the null check occurs before the variable declaration.
+      <p>For example, in the following class, a call to the String length() method is made after verifying the String variable is not null.</p>
+      <p><img src="images/extract-local-var-before.png" alt="Before"/></p>
+      <p>If we select the <b>s.length()</b> call and choose to extract this to a local variable to replace all occurrences, the result is:</p>
+      <p><img src="images/extract-local-var-after.png" alt="Before"/></p>
+      <p>Note how the declaration is after the if statement to ensure that the check for null occurs first</p>
+    </td>
+  </tr>
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