Files
java-design-patterns/commander/src/main/java/com/iluwatar/commander/messagingservice/MessagingService.java
2020-08-15 21:47:39 +04:00

102 lines
3.8 KiB
Java

/*
* The MIT License
* Copyright © 2014-2019 Ilkka Seppälä
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
package com.iluwatar.commander.messagingservice;
import com.iluwatar.commander.Service;
import com.iluwatar.commander.exceptions.DatabaseUnavailableException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* The MessagingService is used to send messages to user regarding their order and payment status.
* In case an error is encountered in payment and this service is found to be unavailable, the order
* is added to the {@link com.iluwatar.commander.employeehandle.EmployeeDatabase}.
*/
public class MessagingService extends Service {
private static final Logger LOGGER = LoggerFactory.getLogger(MessagingService.class);
enum MessageToSend {
PAYMENT_FAIL, PAYMENT_TRYING, PAYMENT_SUCCESSFUL
}
class MessageRequest {
String reqId;
MessageToSend msg;
MessageRequest(String reqId, MessageToSend msg) {
this.reqId = reqId;
this.msg = msg;
}
}
public MessagingService(MessagingDatabase db, Exception... exc) {
super(db, exc);
}
/**
* Public method which will receive request from {@link com.iluwatar.commander.Commander}.
*/
public String receiveRequest(Object... parameters) throws DatabaseUnavailableException {
var messageToSend = (int) parameters[0];
var id = generateId();
MessageToSend msg;
if (messageToSend == 0) {
msg = MessageToSend.PAYMENT_FAIL;
} else if (messageToSend == 1) {
msg = MessageToSend.PAYMENT_TRYING;
} else { //messageToSend == 2
msg = MessageToSend.PAYMENT_SUCCESSFUL;
}
var req = new MessageRequest(id, msg);
return updateDb(req);
}
protected String updateDb(Object... parameters) throws DatabaseUnavailableException {
var req = (MessageRequest) parameters[0];
if (this.database.get(req.reqId) == null) { //idempotence, in case db fails here
database.add(req); //if successful:
LOGGER.info(sendMessage(req.msg));
return req.reqId;
}
return null;
}
String sendMessage(MessageToSend m) {
if (m.equals(MessageToSend.PAYMENT_SUCCESSFUL)) {
return "Msg: Your order has been placed and paid for successfully!"
+ " Thank you for shopping with us!";
} else if (m.equals(MessageToSend.PAYMENT_TRYING)) {
return "Msg: There was an error in your payment process,"
+ " we are working on it and will return back to you shortly."
+ " Meanwhile, your order has been placed and will be shipped.";
} else {
return "Msg: There was an error in your payment process."
+ " Your order is placed and has been converted to COD."
+ " Please reach us on CUSTOMER-CARE-NUBER in case of any queries."
+ " Thank you for shopping with us!";
}
}
}