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copied!<p>Besides your example which declares local fields outside the <code>try</code> block in order to be accessible inside the <code>catch</code> block, one very simple way of handling this is to dump the state of the class out in the <code>Exception</code> using the class's overridden <code>toString</code> method. Granted, this is only useful in <code>Class</code>es that maintain state. </p> <pre><code>try { setMyValue(someObject.getValue()); doSomething(getMyValue()); } catch (BadThingsHappenException bthe) { // consider this a RuntimeException wrapper class throw new UnhandledException(toString(), bthe); } </code></pre> <p>Your <code>toString()</code> would need to be overridden:</p> <pre><code>public String toString() { return super.toString() + "[myValue: " + getMyValue() +"]"; } </code></pre> <p><strong>edit:</strong></p> <p>another idea:</p> <p>You could maintain state in a <a href="http://java.sun.com/javase/6/docs/api/java/lang/ThreadLocal.html" rel="nofollow noreferrer"><code>ThreadLocal</code></a> debug context. Suppose you create a class called <code>MyDebugUtils</code> which holds a <code>ThreadLocal</code> that contains a Map per Thread. You allow for static access to this <code>ThreadLocal</code> and maintenance methods (ie, to clear the context when your debugging is finished). </p> <p>The interface could be:</p> <pre><code>public static void setValue(Object key, Object value) public static void clearContext() public static String getContextString() </code></pre> <p>and in our example:</p> <pre><code>try { MyDebugUtils.setValue("someObeject.value", someObject.getValue()); doSomething(someObject.getValue()); } catch (BadThingsHappenException bthe) { // consider this a RuntimeException wrapper class throw new UnhandledException(MyDebugUtils.getContextString(), bthe); } finally { MyDebugUtils.clearContext(); } </code></pre> <p>There might be some issues that you would want to iron out, such as handling cases where your <code>doSomething</code> method also contains a <code>try/catch/finally</code> set that clears the debug context. This could be handled by allowing for finer granularity in the context Map than just the Thread in the process:</p> <pre><code>public static void setValue(Object contextID, Object key, Object value) public static void clearContext(Object contextID) public static String getContextString(Object contextID) </code></pre>

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