Fix #663 NPE during context stop

Avoid adding null beans
protect against null beans.

jetty-server/src/main/java/org/eclipse/jetty/server/Server.java

@@ -654,7 +654,8 @@ public class Server extends HandlerWrapper implements Attributes
     @Override
     public void setAttribute(String name, Object attribute)
     {
-        addBean(attribute);
+        Object old=_attributes.getAttribute(name);
+        updateBean(old,attribute);        
         _attributes.setAttribute(name, attribute);
     }
 

jetty-util/src/main/java/org/eclipse/jetty/util/component/ContainerLifeCycle.java

@@ -246,7 +246,7 @@ public class ContainerLifeCycle extends AbstractLifeCycle implements Container,
 
     public boolean addBean(Object o, Managed managed)
     {
-        if (contains(o))
+        if (o==null || contains(o))
             return false;
 
         Bean new_bean = new Bean(o);
@@ -751,6 +751,8 @@ public class ContainerLifeCycle extends AbstractLifeCycle implements Container,
 
         private Bean(Object b)
         {
+            if (b==null)
+                throw new NullPointerException();
             _bean = b;
         }
 

jetty-webapp/src/test/java/org/eclipse/jetty/webapp/ClasspathPatternTest.java

@@ -66,8 +66,8 @@ public class ClasspathPatternTest
     public void testExplicitNestedMatch()
     {
         assertTrue(pattern.match("org.example.Nested$Something"));
-        
         assertFalse(pattern.match("org.example.Nested$Minus"));
+        assertTrue(pattern.match("org.example.Nested$Other"));
     }
 
     @Test