Remove isConnect API

Signed-off-by: sahuang <xiaohai.xu@zilliz.com>

examples/src/main/java/MilvusClientExample.java

@@ -78,9 +78,6 @@ public class MilvusClientExample {
       throw e;
     }
 
-    // Check whether we are connected
-    boolean connected = client.isConnected();
-
     // Create a collection with the following collection mapping
     final String collectionName = "example"; // collection name
     final long dimension = 128; // dimension of each vector

src/main/java/io/milvus/client/MilvusClient.java

@@ -59,12 +59,6 @@ public interface MilvusClient {
    */
   Response connect(ConnectParam connectParam) throws ConnectFailedException;
 
-  /**
-   * @return <code>true</code> if the client is connected to Milvus server and the channel's
-   *     connectivity state is READY.
-   */
-  boolean isConnected();
-
   /**
    * Disconnects from Milvus server
    *

src/main/java/io/milvus/client/MilvusGrpcClient.java

@@ -114,15 +114,6 @@ public class MilvusGrpcClient implements MilvusClient {
     return new Response(Response.Status.SUCCESS);
   }
 
-  @Override
-  public boolean isConnected() {
-    if (channel == null) {
-      return false;
-    }
-    ConnectivityState connectivityState = channel.getState(false);
-    return connectivityState == ConnectivityState.READY;
-  }
-
   @Override
   public Response disconnect() throws InterruptedException {
     if (!channelIsReadyOrIdle()) {

src/test/java/io/milvus/client/MilvusGrpcClientTest.java

@@ -116,8 +116,6 @@ class MilvusClientTest {
             .build();
     client.connect(connectParam);
     TimeUnit.SECONDS.sleep(2);
-    // Channel should be idle
-    assertFalse(client.isConnected());
     // A new RPC would take the channel out of idle mode
     assertTrue(client.listCollections().ok());
   }
@@ -162,11 +160,6 @@ class MilvusClientTest {
     assertThrows(ConnectFailedException.class, () -> client.connect(connectParam));
   }
 
-  @org.junit.jupiter.api.Test
-  void isConnected() {
-    assertTrue(client.isConnected());
-  }
-
   @org.junit.jupiter.api.Test
   void createInvalidCollection() {
     String invalidCollectionName = "╯°□°）╯";