Explorer

The explorer API provides convinience methods to interact with the underlying blockchain via a bootstrap node. It also provides a mechanism to validate the NKN Address for correctness.

Valid Address

Check if the provided address is structurally valid or not

String address = "<nknAddress>";boolean isValid = NKNExplorer.isAddressValid(address);if ( isValid ){    System.out.println("Address is valid");} else {    System.out.println("Address is not valid");}

Wallet

Resolve Name

Resolve a friendly name and get the corresponding NKN Address from the naming service.

String nknAddress = NKNExplorer.Wallet.resolveNamedAddress("friendlyname");

Query Balance

Query the balance of an NKN Address

BigDecimal balance = NKNExplorer.Wallet.queryBalance("<nknAddress>");

Get Nonce

Get the nonce

long nonce = NKNExplorer.Wallet.getNonce("<nknAddress>");

Blockchain

Get Block Count

Get the block count

int blockCount = NKNExplorer.BlockChain.getBlockCount();

Get Latest Block Hash

Get the hash corresponding to the latest block

NKNExplorer.BlockChain.LatestBlockHash latestBlockHash = NKNExplorer.BlockChain.getLatestBlockHash();System.out.println(latestBlockHash.hash);System.out.println(latestBlockHash.height);

Subscription

Get Subscribers

Get a list of subscribers for a given topic.

String topic = "topicName";final NKNExplorer.Subscription.Subscriber[] subscribers = NKNExplorer.Subscription.getSubscribers(topic);System.out.println("Subscribers of '" + topic + "':");for (NKNExplorer.Subscription.Subscriber subscriber : subscribers) {    System.out.println("Subscriber Identifier: " + subscriber.fullClientIdentifier);    System.out.println("Meta: " + subscriber.meta);
}System.out.println("Total: " + subscribers.length + " subscribers");

tip

There is an overloaded method available to get subscribers which gives the option to filter subscribers basis offset, limit, metadata, transaction pool along with topic.

Get Subscriber Count

Get the number of subscribers subscribed to a topic

String topic = "topicName";int subscriberCount = NKNExplorer.Subscription.getSubscriberCount(topic);   

Get Subscription Details

Get details of the subscription for a subscriber

String topic = "topicName";String subscriberIdentifier = "identifier";NKNExplorer.Subscription.SubscriptionDetail subscriptionDetail = NKNExplorer.Subscription.getSubscriptionDetail(topic, subscriberIdentifier);
System.out.println("Subscriber Identifier: " + subscriptionDetail.fullClientIdentifier);System.out.println("Topic: " + subscriptionDetail.topic);System.out.println("Meta: " + subscriptionDetail.meta);System.out.println("Expires At: " + subscriptionDetail.expiresAt);