Added MessageIdGenerator for providing unique message IDs in the future.

This commit is contained in:
Kai S. K. Engelbart 2019-12-31 18:10:12 +02:00
parent a418d3efbc
commit b84f05e111

View File

@ -0,0 +1,41 @@
package envoy.data;
/**
* Generates increasing IDs between two numbers.<br>
* <br>
* Project: <strong>envoy-common</strong><br>
* File: <strong>MessageIdGenerator.java</strong><br>
* Created: <strong>31.12.2019</strong><br>
*
* @author Kai S. K. Engelbart
* @since Envoy Common v0.2-alpha
*/
public class MessageIdGenerator {
private final long end;
private long current;
/**
* Creates an instance of {@link MessageIdGenerator}.
*
* @param begin the first ID
* @param end the last ID
*/
public MessageIdGenerator(long begin, long end) {
current = begin;
this.end = end;
}
/**
* @return {@code true} if there are unused IDs remaining
*/
public boolean hasNext() { return current < end; }
/**
* @return the next ID
*/
public long next() {
if (!hasNext()) throw new IllegalStateException("All IDs have been used");
return current++;
}
}