Adding StacklessLogging try-with-resources compatible convenience class

jetty-util/src/main/java/org/eclipse/jetty/util/log/StacklessLogging.java

@@ -0,0 +1,69 @@
+//
+//  ========================================================================
+//  Copyright (c) 1995-2013 Mort Bay Consulting Pty. Ltd.
+//  ------------------------------------------------------------------------
+//  All rights reserved. This program and the accompanying materials
+//  are made available under the terms of the Eclipse Public License v1.0
+//  and Apache License v2.0 which accompanies this distribution.
+//
+//      The Eclipse Public License is available at
+//      http://www.eclipse.org/legal/epl-v10.html
+//
+//      The Apache License v2.0 is available at
+//      http://www.opensource.org/licenses/apache2.0.php
+//
+//  You may elect to redistribute this code under either of these licenses.
+//  ========================================================================
+//
+
+package org.eclipse.jetty.util.log;
+
+/**
+ * A try-with-resources compatible layer for {@link StdErrLog#setHideStacks(boolean) hiding stacktraces} within the scope of the <code>try</code> block when
+ * logging with {@link StdErrLog} implementation.
+ * <p>
+ * Use of other logging implementation cause no effect when using this class
+ * <p>
+ * Example:
+ * 
+ * <pre>
+ * try (StacklessLogging scope = new StacklessLogging(EventDriver.class,Noisy.class))
+ * {
+ *     doActionThatCausesStackTraces();
+ * }
+ * </pre>
+ */
+public class StacklessLogging implements AutoCloseable
+{
+    private final Class<?> clazzes[];
+
+    public StacklessLogging(Class<?>... classesToSquelch)
+    {
+        this.clazzes = classesToSquelch;
+        hideStacks(true);
+    }
+
+    @Override
+    public void close() throws Exception
+    {
+        hideStacks(false);
+    }
+
+    private void hideStacks(boolean hide)
+    {
+        for (Class<?> clazz : clazzes)
+        {
+            Logger log = Log.getLogger(clazz);
+            if (log == null)
+            {
+                // not interested in classes without loggers
+                continue;
+            }
+            if (log instanceof StdErrLog)
+            {
+                // only operate on loggers that are of type StdErrLog
+                ((StdErrLog)log).setHideStacks(hide);
+            }
+        }
+    }
+}