DATAMONGO-861 - Add support for $cond and $ifNull operators in aggregation operations.

pom.xml

@@ -5,7 +5,7 @@
 
 	<groupId>org.springframework.data</groupId>
 	<artifactId>spring-data-mongodb-parent</artifactId>
-	<version>1.10.0.BUILD-SNAPSHOT</version>
+	<version>1.10.0.DATAMONGO-861-SNAPSHOT</version>
 	<packaging>pom</packaging>
 
 	<name>Spring Data MongoDB</name>

spring-data-mongodb-cross-store/pom.xml

@@ -6,7 +6,7 @@
 	<parent>
 		<groupId>org.springframework.data</groupId>
 		<artifactId>spring-data-mongodb-parent</artifactId>
-		<version>1.10.0.BUILD-SNAPSHOT</version>
+		<version>1.10.0.DATAMONGO-861-SNAPSHOT</version>
 		<relativePath>../pom.xml</relativePath>
 	</parent>
 
@@ -48,7 +48,7 @@
 		<dependency>
 			<groupId>org.springframework.data</groupId>
 			<artifactId>spring-data-mongodb</artifactId>
-			<version>1.10.0.BUILD-SNAPSHOT</version>
+			<version>1.10.0.DATAMONGO-861-SNAPSHOT</version>
 		</dependency>
 
 		<dependency>

spring-data-mongodb-distribution/pom.xml

@@ -13,7 +13,7 @@
 	<parent>
 		<groupId>org.springframework.data</groupId>
 		<artifactId>spring-data-mongodb-parent</artifactId>
-		<version>1.10.0.BUILD-SNAPSHOT</version>
+		<version>1.10.0.DATAMONGO-861-SNAPSHOT</version>
 		<relativePath>../pom.xml</relativePath>
 	</parent>
 

spring-data-mongodb-log4j/pom.xml

@@ -5,7 +5,7 @@
 	<parent>
 		<groupId>org.springframework.data</groupId>
 		<artifactId>spring-data-mongodb-parent</artifactId>
-		<version>1.10.0.BUILD-SNAPSHOT</version>
+		<version>1.10.0.DATAMONGO-861-SNAPSHOT</version>
 		<relativePath>../pom.xml</relativePath>
 	</parent>
 

spring-data-mongodb/pom.xml

@@ -11,7 +11,7 @@
 	<parent>
 		<groupId>org.springframework.data</groupId>
 		<artifactId>spring-data-mongodb-parent</artifactId>
-		<version>1.10.0.BUILD-SNAPSHOT</version>
+		<version>1.10.0.DATAMONGO-861-SNAPSHOT</version>
 		<relativePath>../pom.xml</relativePath>
 	</parent>
 

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

@@ -25,7 +25,7 @@
 import org.springframework.data.domain.Sort.Direction;
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.ExposedField;
 import org.springframework.data.mongodb.core.aggregation.ExposedFields.FieldReference;
-import org.springframework.data.mongodb.core.aggregation.Fields.*;
+import org.springframework.data.mongodb.core.aggregation.Fields.AggregationField;
 import org.springframework.data.mongodb.core.aggregation.FieldsExposingAggregationOperation.InheritsFieldsAggregationOperation;
 import org.springframework.data.mongodb.core.query.Criteria;
 import org.springframework.data.mongodb.core.query.NearQuery;
@@ -331,13 +331,13 @@ public static MatchOperation match(Criteria criteria) {
 	}
 
 	/**
-	 * Creates a new {@link OutOperation} using the given collection name. This operation must be the last operation
-	 * in the pipeline.
+	 * Creates a new {@link OutOperation} using the given collection name. This operation must be the last operation in
+	 * the pipeline.
 	 *
 	 * @param outCollectionName collection name to export aggregation results. The {@link OutOperation} creates a new
-	 * collection in the current database if one does not already exist. The collection is
-	 * not visible until the aggregation completes. If the aggregation fails, MongoDB does
-	 * not create the collection. Must not be {@literal null}.
+	 *          collection in the current database if one does not already exist. The collection is not visible until the
+	 *          aggregation completes. If the aggregation fails, MongoDB does not create the collection. Must not be
+	 *          {@literal null}.
 	 * @return
 	 */
 	public static OutOperation out(String outCollectionName) {
@@ -372,6 +372,68 @@ public static LookupOperation lookup(Field from, Field localField, Field foreign
 		return new LookupOperation(from, localField, foreignField, as);
 	}
 
+	/**
+	 * Creates a new {@link IfNullOperator} for the given {@code field} and {@code replacement} value.
+	 *
+	 * @param field must not be {@literal null}.
+	 * @param replacement must not be {@literal null}.
+	 * @return never {@literal null}.
+	 * @since 1.10
+	 */
+	public static IfNullOperator ifNull(String field, Object replacement) {
+		return IfNullOperator.newBuilder().ifNull(field).thenReplaceWith(replacement);
+	}
+
+	/**
+	 * Creates a new {@link IfNullOperator} for the given {@link Field} and {@link Field} to obtain a value from.
+	 *
+	 * @param field must not be {@literal null}.
+	 * @param replacement must not be {@literal null}.
+	 * @return never {@literal null}.
+	 * @since 1.10
+	 */
+	public static IfNullOperator ifNull(Field field, Field replacement) {
+		return IfNullOperator.newBuilder().ifNull(field).thenReplaceWith(replacement);
+	}
+
+	/**
+	 * Creates a new {@link IfNullOperator} for the given {@link Field} and {@code replacement} value.
+	 *
+	 * @param field must not be {@literal null}.
+	 * @param replacement must not be {@literal null}.
+	 * @return never {@literal null}.
+	 * @since 1.10
+	 */
+	public static IfNullOperator ifNull(Field field, Object replacement) {
+		return IfNullOperator.newBuilder().ifNull(field).thenReplaceWith(replacement);
+	}
+
+	/**
+	 * Creates a new {@link ConditionalOperator} for the given {@link Field} that holds a {@literal boolean} value.
+	 *
+	 * @param booleanField must not be {@literal null}.
+	 * @param then must not be {@literal null}.
+	 * @param otherwise must not be {@literal null}.
+	 * @return never {@literal null}.
+	 * @since 1.10
+	 */
+	public static ConditionalOperator conditional(Field booleanField, Object then, Object otherwise) {
+		return ConditionalOperator.newBuilder().when(booleanField).then(then).otherwise(otherwise);
+	}
+
+	/**
+	 * Creates a new {@link ConditionalOperator} for the given {@link Criteria}.
+	 *
+	 * @param criteria must not be {@literal null}.
+	 * @param then must not be {@literal null}.
+	 * @param otherwise must not be {@literal null}.
+	 * @return never {@literal null}.
+	 * @since 1.10
+	 */
+	public static ConditionalOperator conditional(Criteria criteria, Object then, Object otherwise) {
+		return ConditionalOperator.newBuilder().when(criteria).then(then).otherwise(otherwise);
+	}
+
 	/**
 	 * Creates a new {@link Fields} instance for the given field names.
 	 *