org.apache.juneau.utils.IdGenerators Maven / Gradle / Ivy
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package org.apache.juneau.utils;
import java.util.concurrent.atomic.*;
/**
* Predefined ID generators.
*/
public class IdGenerators {
/**
* Creates an ID generator using {@link AtomicInteger} initialized to value 1.
*
* @param initValue The initial value.
* @return A new ID generator.
*/
public static IdGenerator createIntGenerator(final int initValue) {
return new IdGenerator() {
private final AtomicInteger i = new AtomicInteger(initValue);
@Override /* IdGenerator */
public synchronized Integer next() {
return i.getAndIncrement();
}
@Override
public synchronized void lb(Integer k) {
i.set(Math.max(k + 1, i.get()));
}
};
}
/**
* Creates an ID generator using {@link AtomicInteger} initialized to the specified value.
*
* @return A new ID generator.
*/
public static IdGenerator createIntGenerator() {
return createIntGenerator(1);
}
/**
* Creates an ID generator using {@link AtomicLong} initialized to value 1.
*
* @param initValue The initial value.
* @return A new ID generator.
*/
public static IdGenerator createLongGenerator(final long initValue) {
return new IdGenerator() {
private final AtomicLong l = new AtomicLong(initValue);
@Override /* IdGenerator */
public synchronized Long next() {
return l.getAndIncrement();
}
@Override
public synchronized void lb(Long k) {
l.set(Math.max(k + 1, l.get()));
}
};
}
/**
* Creates an ID generator using {@link AtomicLong} initialized to the specified value.
*
* @return A new ID generator.
*/
public static IdGenerator createLongGenerator() {
return createLongGenerator(1);
}
}