DATAMONGO-1358

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/Aggregation.java

@@ -307,7 +307,13 @@ public static SkipOperation skip(int elementsToSkip) {
 	public static LimitOperation limit(long maxElements) {
 		return new LimitOperation(maxElements);
 	}
-
+	/**
+	 * Creates a new {@link OutOperation} creating new collection.
+	 *
+	 * @param out collection name must not null.
+	 * @return
+	 */
+	public static OutOperation out(String out){return  new OutOperation(out);}
 	/**
 	 * Creates a new {@link MatchOperation} using the given {@link Criteria}.
 	 *

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/aggregation/OutOperation.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.mongodb.core.aggregation;
+
+import com.mongodb.BasicDBObject;
+import com.mongodb.DBObject;
+import org.springframework.util.Assert;
+
+
+/**
+ * Encapsulates the aggregation framework {@code $out}-operation. We recommend to use the static factory method
+ * {@link Aggregation#out(String)} instead of creating instances of this class directly.
+ *
+ * @author Shweta Gupta
+ * @see https://docs.mongodb.org/manual/reference/operator/aggregation/out/
+ * @since 1.9
+ */
+public class OutOperation implements AggregationOperation{
+	private final String out;
+	/**
+	 * @param out Output collection name.
+	 */
+	public OutOperation(String out) {
+		Assert.notNull(out, "Out must not be null!");
+		this.out = out;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.mongodb.core.aggregation.AggregationOperation#toDBObject(org.springframework.data.mongodb.core.aggregation.AggregationOperationContext)
+	 */
+	@Override
+	public DBObject toDBObject(AggregationOperationContext context) {
+		return new BasicDBObject("$out",out);
+	}
+}

spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/aggregation/AggregationTests.java

@@ -853,6 +853,43 @@ public void shouldAllowGroupByIdFields() {
 		assertThat(String.valueOf(firstItem.get("_id")), is("u1"));
 	}
 
+
+
+	/**
+	 * @see DATAMONGO-1358
+	 */
+	@Test
+	public void shouldSupportOutAggregation() {
+
+		mongoTemplate.dropCollection(User.class);
+
+		LocalDateTime now = new LocalDateTime();
+
+		User user1 = new User("u1", new PushMessage("1", "aaa", now.toDate()));
+		User user2 = new User("u2", new PushMessage("2", "bbb", now.minusDays(2).toDate()));
+		User user3 = new User("u3", new PushMessage("3", "ccc", now.minusDays(1).toDate()));
+
+		mongoTemplate.save(user1);
+		mongoTemplate.save(user2);
+		mongoTemplate.save(user3);
+
+		Aggregation agg = newAggregation( //
+				project("id", "msgs"), //
+				unwind("msgs"), //
+				match(where("msgs.createDate").gt(now.minusDays(1).toDate())), //
+				group("id").push("msgs").as("msgs"),out("userDetails") //
+		);
+
+		AggregationResults<DBObject> results = mongoTemplate.aggregate(agg, User.class, DBObject.class);
+		System.out.println(results.getRawResults());
+
+		List<DBObject> mappedResults = mongoTemplate.findAll(DBObject.class,"userDetails");
+
+		DBObject firstItem = mappedResults.get(0);
+	assertThat(firstItem.get("_id"), is(notNullValue()));
+	assertThat(String.valueOf(firstItem.get("_id")), is("u1"));
+}
+
 	/**
 	 * @see DATAMONGO-840
 	 */