[Feat][Spark] Update snakeyaml to 2.x.x version (#312)

* Update snakeyaml to 2.x.x version

 On branch 311-update-snakeyaml
 Changes to be committed:
	modified:   spark/pom.xml
	modified:   spark/src/main/scala/com/alibaba/graphar/EdgeInfo.scala
	modified:   spark/src/main/scala/com/alibaba/graphar/GraphInfo.scala
	modified:   spark/src/main/scala/com/alibaba/graphar/VertexInfo.scala

* Fix code style

 On branch 311-update-snakeyaml
 Changes to be committed:
	modified:   spark/src/main/scala/com/alibaba/graphar/GraphInfo.scala
	modified:   spark/src/main/scala/com/alibaba/graphar/VertexInfo.scala

Author: SemyonSinchenko

spark/pom.xml

@@ -82,7 +82,7 @@
         <dependency>
             <groupId>org.yaml</groupId>
             <artifactId>snakeyaml</artifactId>
-            <version>1.26</version>
+            <version>2.0</version>
         </dependency>
         <dependency>
             <groupId>com.aliyun.odps</groupId>

spark/src/main/scala/com/alibaba/graphar/EdgeInfo.scala

@@ -21,6 +21,7 @@ import org.apache.spark.sql.{SparkSession}
 import org.yaml.snakeyaml.{Yaml, DumperOptions}
 import org.yaml.snakeyaml.constructor.Constructor
 import scala.beans.BeanProperty
+import org.yaml.snakeyaml.LoaderOptions
 
 /** Edge info is a class to store the edge meta information. */
 class EdgeInfo() {
@@ -670,7 +671,7 @@ object EdgeInfo {
     val path = new Path(edgeInfoPath)
     val fs = path.getFileSystem(spark.sparkContext.hadoopConfiguration)
     val input = fs.open(path)
-    val yaml = new Yaml(new Constructor(classOf[EdgeInfo]))
+    val yaml = new Yaml(new Constructor(classOf[EdgeInfo], new LoaderOptions()))
     return yaml.load(input).asInstanceOf[EdgeInfo]
   }
 }

spark/src/main/scala/com/alibaba/graphar/GraphInfo.scala

@@ -21,6 +21,7 @@ import org.apache.spark.sql.{SparkSession}
 import org.yaml.snakeyaml.{Yaml, DumperOptions}
 import org.yaml.snakeyaml.constructor.Constructor
 import scala.beans.BeanProperty
+import org.yaml.snakeyaml.LoaderOptions
 
 /** Main data type in gar enumeration */
 object GarType extends Enumeration {
@@ -366,7 +367,9 @@ object GraphInfo {
     val path = new Path(graphInfoPath)
     val fs = path.getFileSystem(spark.sparkContext.hadoopConfiguration)
     val input = fs.open(path)
-    val yaml = new Yaml(new Constructor(classOf[GraphInfo]))
+    val yaml = new Yaml(
+      new Constructor(classOf[GraphInfo], new LoaderOptions())
+    )
     val graph_info = yaml.load(input).asInstanceOf[GraphInfo]
     if (graph_info.getPrefix == "") {
       val pos = graphInfoPath.lastIndexOf('/')

spark/src/main/scala/com/alibaba/graphar/VertexInfo.scala

@@ -21,6 +21,7 @@ import org.apache.spark.sql.{SparkSession}
 import org.yaml.snakeyaml.{Yaml, DumperOptions}
 import org.yaml.snakeyaml.constructor.Constructor
 import scala.beans.BeanProperty
+import org.yaml.snakeyaml.LoaderOptions
 
 /** VertexInfo is a class to store the vertex meta information. */
 class VertexInfo() {
@@ -288,7 +289,9 @@ object VertexInfo {
     val path = new Path(vertexInfoPath)
     val fs = path.getFileSystem(spark.sparkContext.hadoopConfiguration)
     val input = fs.open(path)
-    val yaml = new Yaml(new Constructor(classOf[VertexInfo]))
+    val yaml = new Yaml(
+      new Constructor(classOf[VertexInfo], new LoaderOptions())
+    )
     return yaml.load(input).asInstanceOf[VertexInfo]
   }
 }