Made HystrixRequestContext Closeable so we can leverage try-with-resources on java 7 and forward

Author: velo

hystrix-core/src/main/java/com/netflix/hystrix/strategy/concurrency/HystrixRequestContext.java

@@ -15,6 +15,7 @@
  */
 package com.netflix.hystrix.strategy.concurrency;
 
+import java.io.Closeable;
 import java.util.concurrent.ConcurrentHashMap;
 
 import com.netflix.hystrix.HystrixCollapser;
@@ -60,7 +61,7 @@
  * <p>
  * <b>NOTE:</b> If <code>initializeContext()</code> is called then <code>shutdown()</code> must also be called or a memory leak will occur.
  */
-public class HystrixRequestContext {
+public class HystrixRequestContext implements Closeable {
 
     /*
      * ThreadLocal on each thread will hold the HystrixRequestVariableState.
@@ -142,4 +143,16 @@ public void shutdown() {
             state = null;
         }
     }
-}
+
+    /**
+     * Shutdown {@link HystrixRequestVariableDefault} objects in this context.
+     * <p>
+     * <b>NOTE: This must be called if <code>initializeContext()</code> was called or a memory leak will occur.</b>
+     *
+     * This method invokes <code>shutdown()</code>
+     */
+    public void close() {
+      shutdown();
+    }
+
+}

hystrix-core/src/test/java/com/netflix/hystrix/HystrixCollapserTest.java

@@ -369,7 +369,7 @@ public void testRequestVariableLifecycle1() throws Exception {
         assertEquals(1, cmdIterator.next().getNumberCollapsed());
 
         // simulate request lifecycle
-        requestContext.shutdown();
+        requestContext.close();
 
         System.out.println("timer.tasks.size() B: " + timer.tasks.size());
 
@@ -452,7 +452,7 @@ public void run() {
         assertEquals(1, cmdIterator.next().getNumberCollapsed());
 
         // simulate request lifecycle
-        requestContext.shutdown();
+        requestContext.close();
 
         HystrixRequestVariableHolder<RequestCollapser<?, ?, ?>> rv = RequestCollapserFactory.getRequestVariable(new TestRequestCollapser(timer, 1).getCollapserKey().name());