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22 package org.onap.dmaap.dmf.mr.backends;
26 * A consumer interface. Consumers pull the next message from a given topic.
29 public interface Consumer
32 * A message interface provide the offset and message
33 * @author nilanjana.maity
36 public interface Message
39 * returning the offset of that particular message
44 * returning the message
51 * Get this consumer's name
57 * Get creation time in ms
60 long getCreateTimeMs ();
63 * Get last access time in ms
66 long getLastAccessMs ();
69 * Get the next message from this source. This method must not block.
70 * @return the next message, or null if none are waiting
72 Message nextMessage ();
75 * Get the next message from this source. This method must not block.
76 * @param atOffset start with the next message at or after atOffset. -1 means next from last request
77 * @return the next message, or null if none are waiting
83 * Close/clean up this consumer
89 * Commit the offset of the last consumed message
95 * Get the offset this consumer is currently at
100 void setOffset(long offset);