package ca.uhn.hl7v2.examples.hoh;
   
   import java.io.IOException;
   import java.util.Map;
   
   import ca.uhn.hl7v2.HL7Exception;
   import ca.uhn.hl7v2.hoh.hapi.server.HohServlet;
   import ca.uhn.hl7v2.model.Message;
   import ca.uhn.hl7v2.protocol.ReceivingApplication;
  import ca.uhn.hl7v2.protocol.ReceivingApplicationException;
  import jakarta.servlet.ServletConfig;
  
  /**
   * Example servlet implementation which receives HL7 messages
   * and uses HAPI to process them.
   */
  public class ExampleHl7OverHttpServletWithOneApplication extends HohServlet {
  
  	/**
  	 * Initialise the servlet
  	 */
  	@Override
  	public void init(ServletConfig theConfig) {
  		
  		/* Servlet should be initialized with an instance of
  		 * ReceivingApplication, which handles incoming messages 
  		 */
  		setApplication(new MyApplication());
  		
  	}
  
  	/**
  	 * The application does the actual processing
  	 */
  	private static class MyApplication implements ReceivingApplication<Message>
  	{
  
  		/**
  		 * processMessage is fired each time a new message 
  		 * arrives. 
  		 * 
  		 * @param theMessage The message which was received
  		 * @param theMetadata A map containing additional information about
  		 *                    the message, where it came from, etc.  
  		 */
  		@Override
  		public Message../../../ca/uhn/hl7v2/model/Message.html#Message">Message processMessage(Message theMessage, Map<String, Object> theMetadata) throws ReceivingApplicationException, HL7Exception {
  			System.out.println("Received message:\n" + theMessage.encode());
  
  			// .. process the message ..
  			
  			/*
  			 * Now reply to the message
  			 */
  			Message response;
  			try {
  				response = theMessage.generateACK();
  			} catch (IOException e) {
  				throw new ReceivingApplicationException(e);
  			}
  			
  			/*
  			 * If something goes horribly wrong, you can throw an 
  			 * exception and an HTTP 500 error will be generated.
  			 * However, it is preferable to return a normal HL7 ACK 
  			 * message with an "AE" response code to note an error. 
  			 */
  			boolean somethingFailed = false;
  
  			return response;
  		}
  
  		/**
  		 * {@inheritDoc}
  		 */
  		@Override
  		public boolean canProcess(Message theMessage) {
  			return true;
  		}
  		
  	}
  	
  }