diff --git a/java/examples/src/main/java/PaddleServingClientExample.java b/java/examples/src/main/java/PaddleServingClientExample.java
index 3505d8c584e5011df2c52c6203bcb5b24c0a8d85..a9334c2f7b903ae27be5a187b77996f2e0c2c1e9 100644
--- a/java/examples/src/main/java/PaddleServingClientExample.java
+++ b/java/examples/src/main/java/PaddleServingClientExample.java
@@ -17,8 +17,8 @@ public class PaddleServingClientExample {
         List<String> fetch = Arrays.asList("price");
         
         Client client = new Client();
-        List<String> endpoints = Arrays.asList("localhost:9393");
-        boolean succ = client.connect(endpoints);
+        String target = "localhost:9393";
+        boolean succ = client.connect(target);
         if (succ != true) {
             System.out.println("connect failed.");
             return false;
@@ -52,8 +52,8 @@ public class PaddleServingClientExample {
         List<String> fetch = Arrays.asList("price");
         
         Client client = new Client();
-        List<String> endpoints = Arrays.asList("localhost:9393");
-        boolean succ = client.connect(endpoints);
+        String target = "localhost:9393";
+        boolean succ = client.connect(target);
         if (succ != true) {
             System.out.println("connect failed.");
             return false;
@@ -82,8 +82,8 @@ public class PaddleServingClientExample {
         List<String> fetch = Arrays.asList("price");
 
         Client client = new Client();
-        List<String> endpoints = Arrays.asList("localhost:9393");
-        boolean succ = client.connect(endpoints);
+        String target = "localhost:9393";
+        boolean succ = client.connect(target);
         if (succ != true) {
             System.out.println("connect failed.");
             return false;
@@ -112,8 +112,8 @@ public class PaddleServingClientExample {
         List<String> fetch = Arrays.asList("prediction");
 
         Client client = new Client();
-        List<String> endpoints = Arrays.asList("localhost:9393");
-        boolean succ = client.connect(endpoints);
+        String target = "localhost:9393";
+        boolean succ = client.connect(target);
         if (succ != true) {
             System.out.println("connect failed.");
             return false;
@@ -150,8 +150,8 @@ public class PaddleServingClientExample {
         List<String> fetch = Arrays.asList("pooled_output");
 
         Client client = new Client();
-        List<String> endpoints = Arrays.asList("localhost:9393");
-        boolean succ = client.connect(endpoints);
+        String target = "localhost:9393";
+        boolean succ = client.connect(target);
         if (succ != true) {
             System.out.println("connect failed.");
             return false;
@@ -231,8 +231,8 @@ public class PaddleServingClientExample {
         List<String> fetch = Arrays.asList("prob");
 
         Client client = new Client();
-        List<String> endpoints = Arrays.asList("localhost:9292");
-        boolean succ = client.connect(endpoints);
+        String target = "localhost:9393";
+        boolean succ = client.connect(target);
         if (succ != true) {
             System.out.println("connect failed.");
             return false;
@@ -269,9 +269,11 @@ public class PaddleServingClientExample {
                 succ = e.batch_predict();
             } else if ("cube_local".equals(arg)) {
                 succ = e.cube_local();
+            } else if ("cube_quant".equals(arg)) {
+                succ = e.cube_local();
             } else {
                 System.out.format("%s not match: java -cp <jar> PaddleServingClientExample <exp>.\n", arg);
-                System.out.println("<exp>: fit_a_line bert model_ensemble asyn_predict batch_predict cube_local.");
+                System.out.println("<exp>: fit_a_line bert model_ensemble asyn_predict batch_predict cube_local cube_quant.");
             }
         }
 
diff --git a/java/src/main/java/io/paddle/serving/client/Client.java b/java/src/main/java/io/paddle/serving/client/Client.java
index ea891877a01722b8cae9d456b5674112c01a4537..b83fe858ea1666ed8278d2dc16458215f23b55fc 100644
--- a/java/src/main/java/io/paddle/serving/client/Client.java
+++ b/java/src/main/java/io/paddle/serving/client/Client.java
@@ -109,10 +109,9 @@ public class Client {
         return resp.getErrCode() == 0;
     }
 
-    public boolean connect(List<String> endpoints) {
-        // TODO
-        //String target = "ipv4:" + String.join(",", endpoints);
-        String target = endpoints.get(0);
+    public boolean connect(String target) {
+        // TODO: target must be NameResolver-compliant URI
+        // https://grpc.github.io/grpc-java/javadoc/io/grpc/ManagedChannelBuilder.html
         try {
             channel_ = ManagedChannelBuilder.forTarget(target)
                 .defaultLoadBalancingPolicy("round_robin")
@@ -484,8 +483,8 @@ public class Client {
         List<String> fetch = Arrays.asList("price");
         
         Client client = new Client();
-        List<String> endpoints = Arrays.asList("localhost:9393");
-        boolean succ = client.connect(endpoints);
+        String endpoint = "localhost:9393";
+        boolean succ = client.connect(endpoint);
         if (succ != true) {
             System.out.println("connect failed.");
             return;