Add test case for loading mappings from properties
diff --git a/gora-mongodb/src/main/java/org/apache/gora/mongodb/store/MongoMapping.java b/gora-mongodb/src/main/java/org/apache/gora/mongodb/store/MongoMapping.java
index f8912c6..b8a5f66 100644
--- a/gora-mongodb/src/main/java/org/apache/gora/mongodb/store/MongoMapping.java
+++ b/gora-mongodb/src/main/java/org/apache/gora/mongodb/store/MongoMapping.java
@@ -21,6 +21,7 @@
 
 import java.util.HashMap;
 import java.util.Locale;
+import java.util.Objects;
 import java.util.regex.Pattern;
 
 import org.slf4j.Logger;
@@ -218,4 +219,20 @@
     DOCUMENT, // a subdocument
     OBJECTID // ObjectId is a 12-byte BSON type
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+    MongoMapping mapping = (MongoMapping) o;
+    return Objects.equals(collectionName, mapping.collectionName) &&
+            Objects.equals(classToDocument, mapping.classToDocument) &&
+            Objects.equals(documentToClass, mapping.documentToClass) &&
+            Objects.equals(documentFields, mapping.documentFields);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(collectionName, classToDocument, documentToClass, documentFields);
+  }
 }
diff --git a/gora-mongodb/src/test/java/org/apache/gora/mongodb/store/TestMongoStoreMappingFromProperties.java b/gora-mongodb/src/test/java/org/apache/gora/mongodb/store/TestMongoStoreMappingFromProperties.java
new file mode 100644
index 0000000..550d25e
--- /dev/null
+++ b/gora-mongodb/src/test/java/org/apache/gora/mongodb/store/TestMongoStoreMappingFromProperties.java
@@ -0,0 +1,89 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.apache.gora.mongodb.store;
+
+import com.mongodb.ServerAddress;
+import junit.framework.Assert;
+import org.apache.commons.io.IOUtils;
+import org.apache.gora.examples.generated.Employee;
+import org.apache.gora.mongodb.MongoContainer;
+import org.apache.gora.store.DataStoreFactory;
+import org.apache.hadoop.conf.Configuration;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.nio.charset.Charset;
+import java.util.Properties;
+
+/**
+ * Test case for loading mappings from properties
+ */
+public class TestMongoStoreMappingFromProperties {
+    private MongoContainer _container;
+
+    @Before
+    public void setUp() {
+        // Container for MongoStore
+        this._container = new MongoContainer("4.2");
+        _container.start();
+    }
+
+    @Test
+    public void testInitialize() throws IOException {
+        // Simple mapping XML
+        String mappingXml = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
+                "<gora-otd>\n" +
+                "    <class name=\"org.apache.gora.examples.generated.Employee\" keyClass=\"java.lang.String\" document=\"frontier\">\n" +
+                "        <field name=\"name\" docfield=\"name\" type=\"string\"/>\n" +
+                "    </class>\n" +
+                "</gora-otd>";
+
+        // Initiate the MongoDB server on the default port
+        ServerAddress address = _container.getServerAddress();
+        int port = address.getPort();
+        String host = address.getHost();
+
+        Properties prop = DataStoreFactory.createProps();
+
+        // Store Mongo server "host:port" in Hadoop configuration
+        // so that MongoStore will be able to get it latter
+        Configuration conf = new Configuration();
+        conf.set(MongoStoreParameters.PROP_MONGO_SERVERS, host + ":" + port);
+
+        // Set mapping XML property
+        prop.setProperty(MongoStore.XML_MAPPING_DEFINITION, mappingXml);
+        MongoStore<String, Employee> mongoStore =
+                DataStoreFactory.createDataStore(MongoStore.class, String.class, Employee.class, conf, prop);
+        MongoMapping actualMapping = mongoStore.getMapping();
+
+        // Read mapping definition from mappingXml
+        MongoMappingBuilder<String, Employee> builder = new MongoMappingBuilder<>(mongoStore);
+        builder.fromInputStream(IOUtils.toInputStream(mappingXml, (Charset) null));
+        MongoMapping expectedMapping = builder.build();
+
+        Assert.assertEquals(expectedMapping, actualMapping);
+    }
+
+    @After
+    public void tearDown() {
+        _container.stop();
+    }
+}