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    <p>Create a <code>Comparator</code> for the job:</p> <pre><code>public class EmployeeComparator implements Comparator&lt;Employee&gt; { private final String type; public EmployeeComparator (String type) { this.type = type; } public int compare(Employee e1, Employee e2) { if (type.equals("name")) { return e1.getName().compareTo(e2.getName()); } return e1.getId().compareTo(e2.getId()); } } </code></pre> <p>Then to use it</p> <pre><code>String type = "name"; // determined at runtime Collections.sort(list, new EmployeeComparator(type)); </code></pre> <p>The reflective version would be similar, except you would look for a method on the object of "get" + type (capitalised) and invoke that and hard cast it to Comparable and use compareTo (I'll try to show the code, but I'm using my iPhone and its a bit of a stretch, but here goes)</p> <pre><code>public class DynamicComparator implements Comparator&lt;Object&gt; { private final String type; // pass in type capitalised, eg "Name" // ie the getter method name minus the "get" public DynamicComparator (String type) { this.type = type; } public int compare(Object o1, Object o2) { // try-catch omitted Method m = o1.getClass().getMethod("get" + type); String s1 = (String)m.invoke(o1); String s2 = (String)m.invoke(o2); return s1.compareTo(s2); } } </code></pre> <hr> <p>OK... Here's how to do it <em>without</em> creating a class, using an anonymous class (with exception handling so code compiles):</p> <pre><code>List&lt;?&gt; list; final String attribute = "Name"; // for example. Also, this is case-sensitive Collections.sort(list, new Comparator&lt;Object&gt;() { public int compare(Object o1, Object o2) { try { Method m = o1.getClass().getMethod("get" + attribute); // Assume String type. If different, you must handle each type String s1 = (String) m.invoke(o1); String s2 = (String) m.invoke(o2); return s1.compareTo(s2); // simply re-throw checked exceptions wrapped in an unchecked exception } catch (SecurityException e) { throw new RuntimeException(e); } catch (NoSuchMethodException e) { throw new RuntimeException(e); } catch (IllegalAccessException e) { throw new RuntimeException(e); } catch (InvocationTargetException e) { throw new RuntimeException(e); } } }); </code></pre>
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    1. COThis looks good and simple. Thanks !! Will try and let you know.
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    2. COThis is definately more cleaner, +1 for that...
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    3. COAwesome man..!! This is exactly what I've been looking for ! Let me try it.
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