hunt.proton.engine.Receiver source code

1 /*
2  * hunt-proton: AMQP Protocol library for D programming language.
3  *
4  * Copyright (C) 2018-2019 HuntLabs
5  *
6  * Website: https://www.huntlabs.net/
7  *
8  * Licensed under the Apache-2.0 License.
9  *
10  */
11 
12 module hunt.proton.engine.Receiver;
13 
14 import hunt.proton.codec.ReadableBuffer;
15 import hunt.proton.codec.WritableBuffer;
16 
17 import hunt.proton.engine.Link;
18 /**
19  * Receiver
20  *
21  */
22 interface Receiver : Link
23 {
24 
25     /**
26      * Adds the specified number of credits.
27      *
28      * The number of link credits initialises to zero.  It is the application's responsibility to call
29      * this method to allow the receiver to receive {@code credits} more deliveries.
30      */
31     public void flow(int credits);
32 
33     /**
34      * Receive message data for the current delivery.
35      *
36      * If the caller takes all the bytes the Receiver currently has for this delivery then it is removed from
37      * the Connection's work list.
38      *
39      * Before considering a delivery to be complete, the caller should examine {@link Delivery#isPartial()}.  If
40      * the delivery is partial, the caller should call {@link #recv(byte[], int, int)} again to receive
41      * the additional bytes once the Delivery appears again on the Connection work-list.
42      *
43      * TODO might the flags other than IO_WORK in DeliveryImpl also prevent the work list being pruned?
44      * e.g. what if a slow JMS consumer receives a disposition frame containing state=RELEASED? This is not IO_WORK.
45      *
46      * @param bytes the destination array where the message data is written
47      * @param offset index in the array to start writing data at
48      * @param size the maximum number of bytes to write
49      *
50      * @return number of bytes written. -1 if there are no more bytes for the current delivery.
51      *
52      * @see #current()
53      */
54     public int recv(byte[] bytes, int offset, int size);
55 
56     /**
57      * Receive message data for the current delivery.
58      *
59      * @param buffer the buffer to write the message data.
60      *
61      * @return number of bytes written. -1 if there are no more bytes for the current delivery.
62      */
63     public int recv(WritableBuffer buffer);
64 
65     /**
66      * Receive message data for the current delivery returning the data in a Readable buffer.
67      *
68      * The delivery will return an empty buffer if there is no pending data to be read or if all
69      * data has been read either by a previous call to this method or by a call to one of the other
70      * receive methods.
71      *
72      * @return a ReadableBuffer that contains the currently available data for the current delivery.
73      */
74     public ReadableBuffer recv();
75 
76     public void drain(int credit);
77 
78     /**
79      * {@inheritDoc}
80      *
81      * TODO document what this method conceptually does and when you should use it.
82      */
83     public bool advance();
84 
85     public bool draining();
86 
87     public void setDrain(bool drain);
88 
89 }