DATACMNS-921 - ResultProcessor now gracefully falls back to approximate collections if necessary.

When handling collection results, we now create an approximate collection in case the creation of the exact same collection fails.

src/test/java/org/springframework/data/repository/query/ResultProcessorUnitTests.java

@@ -245,6 +245,20 @@ public class ResultProcessorUnitTests {
 		assertThat(result, is(instanceOf(WrappingDto.class)));
 	}
 
+	/**
+	 * @see DATACMNS-921
+	 */
+	@Test
+	public void fallsBackToApproximateCollectionIfNecessary() throws Exception {
+
+		ResultProcessor processor = getProcessor("findAllProjection");
+
+		SpecialList<Sample> specialList = new SpecialList<Sample>(new Object());
+		specialList.add(new Sample("Dave", "Matthews"));
+
+		processor.processResult(specialList);
+	}
+
 	private static ResultProcessor getProcessor(String methodName, Class<?>... parameters) throws Exception {
 		return getQueryMethod(methodName, parameters).getResultProcessor();
 	}
@@ -311,4 +325,11 @@ public class ResultProcessorUnitTests {
 		@Value("#{target.firstname + ' ' + target.lastname}")
 		String getFullName();
 	}
+
+	static class SpecialList<E> extends ArrayList<E> {
+
+		private static final long serialVersionUID = -6539525376878522158L;
+
+		public SpecialList(Object dummy) {}
+	}
 }