[KYUUBI #1088] Refactor java version dto to scala version

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### _Why are the changes needed?_
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### _How was this patch tested?_
- [ ] Add some test cases that check the changes thoroughly including negative and positive cases if possible

- [ ] Add screenshots for manual tests if appropriate

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Closes #1089 from yanghua/KYUUBI-1088.

Closes #1088

c905bde3 [yanghua] [KYUUBI #1088] Refactor java version dto to scala version

Authored-by: yanghua <yanghua1127@gmail.com>
Signed-off-by: ulysses-you <ulyssesyou@apache.org>

kyuubi-server/src/main/java/org/apache/kyuubi/server/api/v1/dto/SessionOpenRequest.java

@@ -1,72 +0,0 @@
-/*
- * 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.kyuubi.server.api.v1.dto;
-
-import java.util.Map;
-
-public class SessionOpenRequest {
-
-  private int protocolVersion;
-  private String user;
-  private String password;
-  private String ipAddr;
-  private Map configs;
-
-  public SessionOpenRequest() {
-  }
-
-  public int getProtocolVersion() {
-    return protocolVersion;
-  }
-
-  public void setProtocolVersion(int protocolVersion) {
-    this.protocolVersion = protocolVersion;
-  }
-
-  public String getUser() {
-    return user;
-  }
-
-  public void setUser(String user) {
-    this.user = user;
-  }
-
-  public String getPassword() {
-    return password;
-  }
-
-  public void setPassword(String password) {
-    this.password = password;
-  }
-
-  public String getIpAddr() {
-    return ipAddr;
-  }
-
-  public void setIpAddr(String ipAddr) {
-    this.ipAddr = ipAddr;
-  }
-
-  public Map<String, String> getConfigs() {
-    return configs;
-  }
-
-  public void setConfigs(Map<String, String> configs) {
-    this.configs = configs;
-  }
-}

kyuubi-server/src/main/scala/org/apache/kyuubi/server/api/v1/SessionsResource.scala

@@ -22,10 +22,8 @@ import com.fasterxml.jackson.module.scala.DefaultScalaModule
 import javax.ws.rs.{Consumes, GET, Path, POST, Produces}
 import javax.ws.rs.core.MediaType
 import org.apache.hive.service.rpc.thrift.TProtocolVersion
-import scala.collection.JavaConverters.mapAsScalaMapConverter
 
 import org.apache.kyuubi.server.api.ApiRequestContext
-import org.apache.kyuubi.server.api.v1.dto.{SessionOpenedCount, SessionOpenRequest}
 
 @Produces(Array(MediaType.APPLICATION_JSON))
 private[v1] class SessionsResource extends ApiRequestContext {
@@ -34,23 +32,20 @@ private[v1] class SessionsResource extends ApiRequestContext {
 
   @GET
   @Path("count")
-  def sessionCount(): SessionOpenedCount = {
-    val sessionOpenedCount = new SessionOpenedCount()
-    sessionOpenedCount.setOpenSessionCount(
-      backendService.sessionManager.getOpenSessionCount
-    )
-    sessionOpenedCount
+  def sessionCount(): String = {
+    mapper.writeValueAsString(SessionOpenCount(backendService.sessionManager.getOpenSessionCount))
   }
 
   @POST
   @Consumes(Array(MediaType.APPLICATION_JSON))
-  def openSession(request : SessionOpenRequest): String = {
+  def openSession(req : String): String = {
+    val request = mapper.readValue(req, classOf[SessionOpenRequest])
     val sessionHandle = backendService.openSession(
-      TProtocolVersion.findByValue(request.getProtocolVersion),
-      request.getUser,
-      request.getPassword,
-      request.getIpAddr,
-      request.getConfigs.asScala.toMap)
+      TProtocolVersion.findByValue(request.protocolVersion),
+      request.user,
+      request.password,
+      request.ipAddr,
+      request.configs)
     mapper.writeValueAsString(sessionHandle)
   }
 }

kyuubi-server/src/main/scala/org/apache/kyuubi/server/api/v1/dto.scala

@@ -15,40 +15,14 @@
  * limitations under the License.
  */
 
-package org.apache.kyuubi.server.api.v1.dto;
+package org.apache.kyuubi.server.api.v1
 
-import java.io.Serializable;
-import java.util.Objects;
+case class SessionOpenCount(openSessionCount: Int)
 
-public class SessionOpenedCount implements Serializable {
-
-  private int openSessionCount;
-
-  public SessionOpenedCount() {
-  }
-
-  public int getOpenSessionCount() {
-    return openSessionCount;
-  }
-
-  public void setOpenSessionCount(int openSessionCount) {
-    this.openSessionCount = openSessionCount;
-  }
-
-  @Override
-  public boolean equals(Object o) {
-    if (this == o) {
-      return true;
-    }
-    if (!(o instanceof SessionOpenedCount)) {
-      return false;
-    }
-    SessionOpenedCount that = (SessionOpenedCount) o;
-    return openSessionCount == that.getOpenSessionCount();
-  }
-
-  @Override
-  public int hashCode() {
-    return Objects.hash(openSessionCount);
-  }
-}
+case class SessionOpenRequest(
+  protocolVersion: Int,
+  user: String,
+  password: String,
+  ipAddr: String,
+  configs: Map[String, String]
+)

kyuubi-server/src/test/scala/org/apache/kyuubi/server/api/v1/SessionsResourceSuite.scala

@@ -28,7 +28,6 @@ import org.junit.Test
 
 import org.apache.kyuubi.server.RestFrontendServiceSuite
 import org.apache.kyuubi.server.RestFrontendServiceSuite.{OBJECT_MAPPER, TEST_SERVER_PORT}
-import org.apache.kyuubi.server.api.v1.dto.{SessionOpenedCount, SessionOpenRequest}
 import org.apache.kyuubi.session.SessionHandle
 
 class SessionsResourceSuite extends JerseyTest {
@@ -42,20 +41,16 @@ class SessionsResourceSuite extends JerseyTest {
 
   @Test
   def testOpenAndCountSession: Unit = {
-    val requestObj = new SessionOpenRequest
-    requestObj.setProtocolVersion(1)
-    requestObj.setUser("admin")
-    requestObj.setPassword("123456")
-    requestObj.setIpAddr("localhost")
-    val configs = new java.util.HashMap[String, String]
-    configs.put("testConfig", "testValue")
-    requestObj.setConfigs(configs)
+    val requestObj = SessionOpenRequest(
+      1, "admin", "123456", "localhost", Map("testConfig" -> "testValue"))
+
+    val requestObjStr = OBJECT_MAPPER.writeValueAsString(requestObj)
 
     RestFrontendServiceSuite.withKyuubiRestServer {
       (_, _, _) =>
         var response = target(s"api/v1/sessions")
           .request(MediaType.APPLICATION_JSON_TYPE)
-          .post(Entity.entity(requestObj, MediaType.APPLICATION_JSON_TYPE))
+          .post(Entity.entity(requestObjStr, MediaType.APPLICATION_JSON_TYPE))
 
         assert(200 == response.getStatus)
 
@@ -66,12 +61,10 @@ class SessionsResourceSuite extends JerseyTest {
         assert(sessionHandle.identifier != null)
 
         // verify the open session count
-        val expectedCount = new SessionOpenedCount()
-        expectedCount.setOpenSessionCount(1)
-
         response = target("api/v1/sessions/count").request().get()
-        val responseObj = response.readEntity(classOf[SessionOpenedCount])
-        assert(responseObj.equals(expectedCount))
+        val openedSessionCount = OBJECT_MAPPER.readValue(
+          response.readEntity(classOf[String]), classOf[SessionOpenCount])
+        assert(openedSessionCount.openSessionCount == 1)
     }
   }