Globally Centralized Configuration (Java)

Central configuration repository client using Zookeeper. Build on top of Zookeeper using Curator Framework https://github.com/Netflix/curator

General Overview

• Java Application connects to set of Zookeeper servers using Curator Framework
• Fetches recent configuration settings (property file) and maintains local copy in HashMap for quick lookups
• Client watches znode for changes and updates local HashMap when configuration changes
• Optionally client may add listeners on each configuration key to handle onChange events

Example

// Zookeeper CuratorFramework Connections
CuratorFramework zooClient = CuratorFrameworkFactory.builder().namespace("curatordemo")
			.connectString("localhost:2181").retryPolicy(new ExponentialBackoffRetry(1000, 3))
			.connectionTimeoutMs(30000).build();
zooClient.start();

// Configuration Manager Initialization
ConfManager confManager = ConfManager.getInstance();
confManager.setDataFormat(CONF_DATA_FORMAT.JSON); // assumes data to be in JSON
confManager.setZookeeperPath("/sample-path"); // optional to set correct global path
confManager.setClient(zooClient);

// Read Properties (String, Integers, Arrays)
String stringProp = confManager.getPropertyAsString("test.stringKey", "defValue");
Integer intProp = confManager.getPropertyAsInteger("test.intKey", 10);
ArrayList<String> arrayProp = confManager.getPropertyAsList("test.arrayKey", Arrays.asList(""));

confManager.addChangeListener("test.changeKeyTest", new ConfManager.PropertyChangeHandler<String>() {
    @Override
    public void handle(String newValue) {
        System.out.println("Received new value: " + newValue);
    }
});