With the open source project messenger4j you will get all you need.
It's an easy to use Java library for building chatbots on the Messenger Platform.
It provides a rich builder API to construct the outgoing messages.
Furthermore it parses the inbound messages to specific java objects and automatically detects their type. For each message type or event you can register corresponding event handlers.
Receiving:
String payload = ...
String signature = ...
MessengerReceiveClient receiveClient = MessengerPlatform.newReceiveClientBuilder("APP_SECRET", "VERIFICATION_TOKEN")
.onTextMessageEvent(event -> System.out.printf("%s: %s", event.getSender().getId(), event.getText()))
.build();
MessengerReceiveClient receiveClient = MessengerPlatform.newReceiveClientBuilder("APP_SECRET", "VERIFICATION_TOKEN")
.onTextMessageEvent(new TextMessageEventHandler() {
@Override
public void handle(TextMessageEvent event) {
System.out.printf("%s: %s", event.getSender().getId(), event.getText());
}
})
.build();
receiveClient.processCallbackPayload(payload, signature);
Sending (simple):
MessengerSendClient sendClient = MessengerPlatform.newSendClientBuilder("PAGE_ACCESS_TOKEN").build();
sendClient.sendTextMessage("RECIPIENT_ID", "Hi there, how are you today?");
Sending (complex):
ReceiptTemplate receipt = ReceiptTemplate.newBuilder("Stephane Crozatier", "12345678902", "USD", "Visa 2345")
.orderUrl("http://petersapparel.parseapp.com/order?order_id=123456")
.timestamp(1428444852L)
.addElements()
.addElement("Classic White T-Shirt", 50F)
.subtitle("100% Soft and Luxurious Cotton")
.quantity(2)
.currency("USD")
.imageUrl("http://petersapparel.parseapp.com/img/whiteshirt.png")
.toList()
.addElement("Classic Gray T-Shirt", 25F)
.subtitle("100% Soft and Luxurious Cotton")
.quantity(1)
.currency("USD")
.imageUrl("http://petersapparel.parseapp.com/img/grayshirt.png")
.toList()
.done()
.addAddress("1 Hacker Way", "Menlo Park", "94025", "CA", "US").street2("").done()
.addSummary(56.14F).subtotal(75.00F).shippingCost(4.95F).totalTax(6.19F).done()
.addAdjustments()
.addAdjustment()
.name("New Customer Discount")
.amount(20.00F)
.toList()
.addAdjustment()
.name("$10 Off Coupon")
.amount(10.00F)
.toList()
.done()
.build();
sendClient.sendTemplate("RECIPIENT_ID", receipt);
BTW: I've built it.