Chapter 15. Clients

Table of Contents

15.1. Native Client
15.1.1. Java Client
15.1.2. CSharp Client (Enterprise Edition Only)
15.2. Memcache Client
15.3. Rest Client

There are currently three ways to connect to a running Hazelcast cluster:

  1. Native Clients

  2. Memcache Clients

  3. REST Client

15.1. Native Client

Native Client enables you to do almost all Hazelcast operations without being a member of the cluster. It connects to one of the cluster members and delegates all cluster wide operations to it or connects to all of them and delegate operations smartly. When the relied cluster member dies, client will transparently switch to another live member.

There can be hundreds, even thousands of clients connected to the cluster. But by default there is 40 threads on server side that will handle all the requests. You may want to increase hazelcast.executor.client.thread.count property for better performance.

Imagine a trading application where all the trading data stored and managed in a 10 node Hazelcast cluster. Swing/Web applications at traders' desktops can use Native Java Client to access and modify the data in the Hazelcast cluster.

Currently Hazelcast has Native Java and C# Client available. C# Client implementation has not yet finished as of version 3.

15.1.1. Java Client

You can do almost all hazelcast operations with Java Client. It already implements the same interface. You must include hazelcast-client.jar into your classpath.

import com.hazelcast.core.HazelcastInstance;
import com.hazelcast.client.HazelcastClient;

import java.util.Map;
import java.util.Collection;

ClientConfig clientConfig = new ClientConfig();
clientConfig.addAddress("", "");

HazelcastInstance client = HazelcastClient.newHazelcastClient(clientConfig);
//All cluster operations that you can do with ordinary HazelcastInstance
Map<String, Customer> mapCustomers = client.getMap("customers");
mapCustomers.put("1", new Customer("Joe", "Smith"));
mapCustomers.put("2", new Customer("Ali", "Selam"));
mapCustomers.put("3", new Customer("Avi", "Noyan"));

Collection<Customer> colCustomers = mapCustomers.values();
for (Customer customer : colCustomers) {
     // process customer

15.1.2. CSharp Client (Enterprise Edition Only)

Not yet implemented as of version 3