53 lines
1.0 KiB
Java
53 lines
1.0 KiB
Java
package envoy.data;
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import java.io.Serializable;
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/**
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* Generates increasing IDs between two numbers.
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*
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* @author Kai S. K. Engelbart
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* @since Envoy Common v0.2-alpha
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*/
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public final class IDGenerator implements Serializable {
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private final long end;
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private long current;
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private static final long serialVersionUID = 0L;
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/**
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* Creates an instance of {@link IDGenerator}.
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*
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* @param begin the first ID
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* @param size the amount of IDs to provide
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* @since Envoy Common v0.2-alpha
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*/
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public IDGenerator(long begin, long size) {
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current = begin;
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end = begin + size;
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}
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@Override
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public String toString() {
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return String.format("IDGenerator[current=%d,end=%d]", current, end);
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}
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/**
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* @return {@code true} if there are unused IDs remaining
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* @since Envoy Common v0.2-alpha
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*/
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public boolean hasNext() {
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return current < end;
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}
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/**
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* @return the next ID
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* @since Envoy Common v0.2-alpha
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*/
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public long next() {
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if (!hasNext())
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throw new IllegalStateException("All IDs have been used");
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return current++;
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}
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}
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