add java json serde test

typesystem/src/main/scala/org/apache/hadoop/metadata/json/Serialization.scala

@@ -22,10 +22,10 @@ import org.apache.jute.compiler.JLong
 import org.apache.hadoop.metadata.types.DataTypes.{MapType, TypeCategory, ArrayType}
 import org.apache.hadoop.metadata._
 import org.apache.hadoop.metadata.types._
-import org.apache.hadoop.metadata.storage.Id
+import org.apache.hadoop.metadata.storage.{ReferenceableInstance, Id}
 import org.json4s.JsonAST.JInt
 import org.json4s._
-import org.json4s.native.Serialization.{read, write => swrite}
+import org.json4s.native.Serialization.{write => swrite, _}
 import org.json4s.reflect.{ScalaType, Reflector}
 import java.util.regex.Pattern
 import java.util.Date
@@ -239,5 +239,17 @@ object Serialization {
       JField("version", JInt(version)) :: Nil) => new Id(id.toLong, version.toInt, className)
   }
 
+  def toJson(value : ITypedReferenceableInstance) : String = {
+    implicit val formats = org.json4s.native.Serialization.formats(NoTypeHints) + new TypedStructSerializer +
+      new TypedReferenceableInstanceSerializer +  new BigDecimalSerializer + new BigIntegerSerializer
 
+    writePretty(value)
+  }
+
+  def fromJson(jsonStr : String) : ITypedReferenceableInstance = {
+    implicit val formats = org.json4s.native.Serialization.formats(NoTypeHints) + new TypedStructSerializer +
+      new TypedReferenceableInstanceSerializer +  new BigDecimalSerializer + new BigIntegerSerializer
+
+    read[ReferenceableInstance](jsonStr)
+  }
 }

typesystem/src/test/java/org/apache/hadoop/metadata/json/SerializationJavaTest.java

+/**
+ * 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.hadoop.metadata.json;
+
+import com.google.common.collect.ImmutableList;
+import org.apache.hadoop.metadata.BaseTest;
+import org.apache.hadoop.metadata.ITypedReferenceableInstance;
+import org.apache.hadoop.metadata.MetadataException;
+import org.apache.hadoop.metadata.Referenceable;
+import org.apache.hadoop.metadata.types.*;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+public class SerializationJavaTest extends BaseTest {
+
+
+    @Before
+    public void setup() throws MetadataException {
+        super.setup();
+    }
+
+    /*
+     * Class Hierarchy is:
+     *   Department(name : String, employees : Array[Person])
+     *   Person(name : String, department : Department, manager : Manager)
+     *   Manager(subordinates : Array[Person]) extends Person
+     *
+     * Persons can have SecurityClearance(level : Int) clearance.
+     */
+    @Test
+    public void test1() throws MetadataException {
+
+        TypeSystem ts = ms.getTypeSystem();
+
+        HierarchicalTypeDefinition<ClassType> deptTypeDef = createClassTypeDef("Department", ImmutableList.<String>of(),
+                createRequiredAttrDef("name", DataTypes.STRING_TYPE),
+                new AttributeDefinition("employees",
+                        String.format("array<%s>", "Person"), Multiplicity.COLLECTION, true, "department")
+        );
+        HierarchicalTypeDefinition<ClassType> personTypeDef = createClassTypeDef("Person", ImmutableList.<String>of(),
+                createRequiredAttrDef("name", DataTypes.STRING_TYPE),
+                new AttributeDefinition("department",
+                        "Department", Multiplicity.REQUIRED, false, "employees"),
+                new AttributeDefinition("manager",
+                        "Manager", Multiplicity.OPTIONAL, false, "subordinates")
+        );
+        HierarchicalTypeDefinition<ClassType> managerTypeDef = createClassTypeDef("Manager",
+                ImmutableList.<String>of("Person"),
+                new AttributeDefinition("subordinates",
+                        String.format("array<%s>", "Person"), Multiplicity.COLLECTION, false, "manager")
+        );
+
+        HierarchicalTypeDefinition<TraitType> securityClearanceTypeDef = createTraitTypeDef("SecurityClearance",
+                ImmutableList.<String>of(),
+                createRequiredAttrDef("level", DataTypes.INT_TYPE)
+        );
+
+        ts.defineTypes(ImmutableList.<StructTypeDefinition>of(),
+                ImmutableList.<HierarchicalTypeDefinition<TraitType>>of(securityClearanceTypeDef),
+                ImmutableList.<HierarchicalTypeDefinition<ClassType>>of(deptTypeDef, personTypeDef, managerTypeDef));
+
+        Referenceable hrDept = new Referenceable("Department");
+        Referenceable john = new Referenceable("Person");
+        Referenceable jane = new Referenceable("Manager", "SecurityClearance");
+
+        hrDept.set("name", "hr");
+        john.set("name", "John");
+        john.set("department", hrDept);
+        jane.set("name", "Jane");
+        jane.set("department", hrDept);
+
+        john.set("manager", jane);
+
+        hrDept.set("employees", ImmutableList.<Referenceable>of(john, jane));
+
+        jane.set("subordinates", ImmutableList.<Referenceable>of(john));
+
+        jane.getTrait("SecurityClearance").set("level", 1);
+
+        ClassType deptType = ts.getDataType(ClassType.class, "Department");
+        ITypedReferenceableInstance hrDept2 = deptType.convert(hrDept, Multiplicity.REQUIRED);
+
+        String hrDeptStr = hrDept2.toString();
+
+        Assert.assertEquals(hrDeptStr, "{\n" +
+                "\tid : (type: Department, id: <unassigned>)\n" +
+                "\tname : \thr\n" +
+                "\temployees : \t[{\n" +
+                "\tid : (type: Person, id: <unassigned>)\n" +
+                "\tname : \tJohn\n" +
+                "\tdepartment : (type: Department, id: <unassigned>)\n" +
+                "\tmanager : (type: Manager, id: <unassigned>)\n" +
+                "}, {\n" +
+                "\tid : (type: Manager, id: <unassigned>)\n" +
+                "\tsubordinates : \t[{\n" +
+                "\tid : (type: Person, id: <unassigned>)\n" +
+                "\tname : \tJohn\n" +
+                "\tdepartment : (type: Department, id: <unassigned>)\n" +
+                "\tmanager : (type: Manager, id: <unassigned>)\n" +
+                "}]\n" +
+                "\tname : \tJane\n" +
+                "\tdepartment : (type: Department, id: <unassigned>)\n" +
+                "\tmanager : <null>\n" +
+                "\n" +
+                "\tSecurityClearance : \t{\n" +
+                "\t\tlevel : \t\t1\n" +
+                "\t}}]\n" +
+                "}");
+
+        String jsonStr = Serialization$.MODULE$.toJson(hrDept2);
+        //System.out.println(jsonStr);
+
+        hrDept2 = Serialization$.MODULE$.fromJson(jsonStr);
+        Assert.assertEquals(hrDept2.toString(), hrDeptStr);
+
+    }
+}
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