make MockInvocation more benign, returning null for proxy instead of UnsupportedOperationException

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/proxy/branches/version-2.0-work@1525260 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/core/src/main/java/org/apache/commons/proxy2/interceptor/InterceptorUtils.java b/core/src/main/java/org/apache/commons/proxy2/interceptor/InterceptorUtils.java
index fb68a2b..7751bc1 100644
--- a/core/src/main/java/org/apache/commons/proxy2/interceptor/InterceptorUtils.java
+++ b/core/src/main/java/org/apache/commons/proxy2/interceptor/InterceptorUtils.java
@@ -18,6 +18,7 @@
 package org.apache.commons.proxy2.interceptor;
 
 import org.apache.commons.proxy2.Interceptor;
+import org.apache.commons.proxy2.Invoker;
 import org.apache.commons.proxy2.ObjectProvider;
 import org.apache.commons.proxy2.provider.ObjectProviderUtils;
 
@@ -71,12 +72,21 @@
         return new ThrowingInterceptor(provider);
     }
 
+    /**
+     * Creates an {@link Interceptor} that delegates to the specified {@link Invoker}.
+     * @param invoker delegate
+     * @return invoker {@link Interceptor}
+     */
+    public static Interceptor invoking(Invoker invoker)
+    {
+        return new InvokerInterceptor(invoker);
+    }
+
 //----------------------------------------------------------------------------------------------------------------------
 // Constructors
 //----------------------------------------------------------------------------------------------------------------------
 
     private InterceptorUtils()
     {
-
     }
 }
diff --git a/core/src/test/java/org/apache/commons/proxy2/util/MockInvocation.java b/core/src/test/java/org/apache/commons/proxy2/util/MockInvocation.java
index 9075e42..92c74e5 100644
--- a/core/src/test/java/org/apache/commons/proxy2/util/MockInvocation.java
+++ b/core/src/test/java/org/apache/commons/proxy2/util/MockInvocation.java
@@ -45,7 +45,7 @@
     @Override
     public Object getProxy()
     {
-        throw new UnsupportedOperationException("Proxy objects aren't supported.");
+        return null;
     }
 
     @Override