A TimeUnit is mainly used to inform time-based methods + *
A {@code TimeUnit} is mainly used to inform time-based methods * how a given timing parameter should be interpreted. For example, * the following code will timeout in 50 milliseconds if the {@link * java.util.concurrent.locks.Lock lock} is not available: * - *
Lock lock = ...; - * if ( lock.tryLock(50L, TimeUnit.MILLISECONDS) ) ... - *+ *
{@code
+ * Lock lock = ...;
+ * if (lock.tryLock(50L, TimeUnit.MILLISECONDS)) ...}
+ *
* while this code will timeout in 50 seconds:
- * - * Lock lock = ...; - * if ( lock.tryLock(50L, TimeUnit.SECONDS) ) ... - *+ *
{@code
+ * Lock lock = ...;
+ * if (lock.tryLock(50L, TimeUnit.SECONDS)) ...}
*
* Note however, that there is no guarantee that a particular timeout
* implementation will be able to notice the passage of time at the
- * same granularity as the given TimeUnit.
+ * same granularity as the given {@code TimeUnit}.
*
* @since 1.5
* @author Doug Lea
*/
public enum TimeUnit {
- NANOSECONDS (0) {
+ NANOSECONDS {
public long toNanos(long d) { return d; }
public long toMicros(long d) { return d/(C1/C0); }
public long toMillis(long d) { return d/(C2/C0); }
@@ -51,7 +51,7 @@ public enum TimeUnit {
public long convert(long d, TimeUnit u) { return u.toNanos(d); }
int excessNanos(long d, long m) { return (int)(d - (m*C2)); }
},
- MICROSECONDS (1) {
+ MICROSECONDS {
public long toNanos(long d) { return x(d, C1/C0, MAX/(C1/C0)); }
public long toMicros(long d) { return d; }
public long toMillis(long d) { return d/(C2/C1); }
@@ -62,7 +62,7 @@ public enum TimeUnit {
public long convert(long d, TimeUnit u) { return u.toMicros(d); }
int excessNanos(long d, long m) { return (int)((d*C1) - (m*C2)); }
},
- MILLISECONDS (2) {
+ MILLISECONDS {
public long toNanos(long d) { return x(d, C2/C0, MAX/(C2/C0)); }
public long toMicros(long d) { return x(d, C2/C1, MAX/(C2/C1)); }
public long toMillis(long d) { return d; }
@@ -73,7 +73,7 @@ public enum TimeUnit {
public long convert(long d, TimeUnit u) { return u.toMillis(d); }
int excessNanos(long d, long m) { return 0; }
},
- SECONDS (3) {
+ SECONDS {
public long toNanos(long d) { return x(d, C3/C0, MAX/(C3/C0)); }
public long toMicros(long d) { return x(d, C3/C1, MAX/(C3/C1)); }
public long toMillis(long d) { return x(d, C3/C2, MAX/(C3/C2)); }
@@ -84,7 +84,7 @@ public enum TimeUnit {
public long convert(long d, TimeUnit u) { return u.toSeconds(d); }
int excessNanos(long d, long m) { return 0; }
},
- MINUTES (4) {
+ MINUTES {
public long toNanos(long d) { return x(d, C4/C0, MAX/(C4/C0)); }
public long toMicros(long d) { return x(d, C4/C1, MAX/(C4/C1)); }
public long toMillis(long d) { return x(d, C4/C2, MAX/(C4/C2)); }
@@ -95,7 +95,7 @@ public enum TimeUnit {
public long convert(long d, TimeUnit u) { return u.toMinutes(d); }
int excessNanos(long d, long m) { return 0; }
},
- HOURS (5) {
+ HOURS {
public long toNanos(long d) { return x(d, C5/C0, MAX/(C5/C0)); }
public long toMicros(long d) { return x(d, C5/C1, MAX/(C5/C1)); }
public long toMillis(long d) { return x(d, C5/C2, MAX/(C5/C2)); }
@@ -106,7 +106,7 @@ public enum TimeUnit {
public long convert(long d, TimeUnit u) { return u.toHours(d); }
int excessNanos(long d, long m) { return 0; }
},
- DAYS (6) {
+ DAYS {
public long toNanos(long d) { return x(d, C6/C0, MAX/(C6/C0)); }
public long toMicros(long d) { return x(d, C6/C1, MAX/(C6/C1)); }
public long toMillis(long d) { return x(d, C6/C2, MAX/(C6/C2)); }
@@ -118,18 +118,6 @@ public enum TimeUnit {
int excessNanos(long d, long m) { return 0; }
};
- /**
- * The index of this unit. This value is no longer used in this
- * version of this class, but is retained for serialization
- * compatibility with previous version.
- */
- private final int index;
-
- /** Internal constructor */
- TimeUnit(int index) {
- this.index = index;
- }
-
// Handy constants for conversion methods
static final long C0 = 1L;
static final long C1 = C0 * 1000L;
@@ -151,91 +139,118 @@ public enum TimeUnit {
return d * m;
}
+ // To maintain full signature compatibility with 1.5, and to improve the
+ // clarity of the generated javadoc (see 6287639: Abstract methods in
+ // enum classes should not be listed as abstract), method convert
+ // etc. are not declared abstract but otherwise act as abstract methods.
+
/**
* Convert the given time duration in the given unit to this
* unit. Conversions from finer to coarser granularities
* truncate, so lose precision. For example converting
- * 999 milliseconds to seconds results in
- * 0. Conversions from coarser to finer granularities
+ * {@code 999} milliseconds to seconds results in
+ * {@code 0}. Conversions from coarser to finer granularities
* with arguments that would numerically overflow saturate to
- * Long.MIN_VALUE if negative or Long.MAX_VALUE
+ * {@code Long.MIN_VALUE} if negative or {@code Long.MAX_VALUE}
* if positive.
*
- * @param duration the time duration in the given unit
- * @param unit the unit of the duration argument
+ * For example, to convert 10 minutes to milliseconds, use: + * {@code TimeUnit.MILLISECONDS.convert(10L, TimeUnit.MINUTES)} + * + * @param sourceDuration the time duration in the given {@code sourceUnit} + * @param sourceUnit the unit of the {@code sourceDuration} argument * @return the converted duration in this unit, - * or Long.MIN_VALUE if conversion would negatively - * overflow, or Long.MAX_VALUE if it would positively overflow. + * or {@code Long.MIN_VALUE} if conversion would negatively + * overflow, or {@code Long.MAX_VALUE} if it would positively overflow. */ - public abstract long convert(long duration, TimeUnit unit); + public long convert(long sourceDuration, TimeUnit sourceUnit) { + throw new AbstractMethodError(); + } /** - * Equivalent to NANOSECONDS.convert(duration, this). + * Equivalent to {@code NANOSECONDS.convert(duration, this)}. * @param duration the duration * @return the converted duration, - * or Long.MIN_VALUE if conversion would negatively - * overflow, or Long.MAX_VALUE if it would positively overflow. + * or {@code Long.MIN_VALUE} if conversion would negatively + * overflow, or {@code Long.MAX_VALUE} if it would positively overflow. * @see #convert */ - public abstract long toNanos(long duration); + public long toNanos(long duration) { + throw new AbstractMethodError(); + } /** - * Equivalent to MICROSECONDS.convert(duration, this). + * Equivalent to {@code MICROSECONDS.convert(duration, this)}. * @param duration the duration * @return the converted duration, - * or Long.MIN_VALUE if conversion would negatively - * overflow, or Long.MAX_VALUE if it would positively overflow. + * or {@code Long.MIN_VALUE} if conversion would negatively + * overflow, or {@code Long.MAX_VALUE} if it would positively overflow. * @see #convert */ - public abstract long toMicros(long duration); + public long toMicros(long duration) { + throw new AbstractMethodError(); + } /** - * Equivalent to MILLISECONDS.convert(duration, this). + * Equivalent to {@code MILLISECONDS.convert(duration, this)}. * @param duration the duration * @return the converted duration, - * or Long.MIN_VALUE if conversion would negatively - * overflow, or Long.MAX_VALUE if it would positively overflow. + * or {@code Long.MIN_VALUE} if conversion would negatively + * overflow, or {@code Long.MAX_VALUE} if it would positively overflow. * @see #convert */ - public abstract long toMillis(long duration); + public long toMillis(long duration) { + throw new AbstractMethodError(); + } /** - * Equivalent to SECONDS.convert(duration, this). + * Equivalent to {@code SECONDS.convert(duration, this)}. * @param duration the duration * @return the converted duration, - * or Long.MIN_VALUE if conversion would negatively - * overflow, or Long.MAX_VALUE if it would positively overflow. + * or {@code Long.MIN_VALUE} if conversion would negatively + * overflow, or {@code Long.MAX_VALUE} if it would positively overflow. * @see #convert */ - public abstract long toSeconds(long duration); + public long toSeconds(long duration) { + throw new AbstractMethodError(); + } /** - * Equivalent to MINUTES.convert(duration, this). + * Equivalent to {@code MINUTES.convert(duration, this)}. * @param duration the duration * @return the converted duration, - * or Long.MIN_VALUE if conversion would negatively - * overflow, or Long.MAX_VALUE if it would positively overflow. + * or {@code Long.MIN_VALUE} if conversion would negatively + * overflow, or {@code Long.MAX_VALUE} if it would positively overflow. * @see #convert + * @since 1.6 */ - public abstract long toMinutes(long duration); + public long toMinutes(long duration) { + throw new AbstractMethodError(); + } /** - * Equivalent to HOURS.convert(duration, this). + * Equivalent to {@code HOURS.convert(duration, this)}. * @param duration the duration * @return the converted duration, - * or Long.MIN_VALUE if conversion would negatively - * overflow, or Long.MAX_VALUE if it would positively overflow. + * or {@code Long.MIN_VALUE} if conversion would negatively + * overflow, or {@code Long.MAX_VALUE} if it would positively overflow. * @see #convert + * @since 1.6 */ - public abstract long toHours(long duration); + public long toHours(long duration) { + throw new AbstractMethodError(); + } /** - * Equivalent to DAYS.convert(duration, this). + * Equivalent to {@code DAYS.convert(duration, this)}. * @param duration the duration * @return the converted duration * @see #convert + * @since 1.6 */ - public abstract long toDays(long duration); + public long toDays(long duration) { + throw new AbstractMethodError(); + } /** * Utility to compute the excess-nanosecond argument to wait, @@ -247,29 +262,31 @@ public enum TimeUnit { abstract int excessNanos(long d, long m); /** - * Performs a timed Object.wait using this time unit. + * Performs a timed {@link Object#wait(long, int) Object.wait} + * using this time unit. * This is a convenience method that converts timeout arguments - * into the form required by the Object.wait method. + * into the form required by the {@code Object.wait} method. * - *
For example, you could implement a blocking poll + *
For example, you could implement a blocking {@code poll} * method (see {@link BlockingQueue#poll BlockingQueue.poll}) * using: * - *
public synchronized Object poll(long timeout, TimeUnit unit) throws InterruptedException {
- * while (empty) {
- * unit.timedWait(this, timeout);
- * ...
- * }
- * }
+ * {@code
+ * public synchronized Object poll(long timeout, TimeUnit unit)
+ * throws InterruptedException {
+ * while (empty) {
+ * unit.timedWait(this, timeout);
+ * ...
+ * }
+ * }}
*
* @param obj the object to wait on
* @param timeout the maximum time to wait. If less than
* or equal to zero, do not wait at all.
- * @throws InterruptedException if interrupted while waiting.
- * @see Object#wait(long, int)
+ * @throws InterruptedException if interrupted while waiting
*/
public void timedWait(Object obj, long timeout)
- throws InterruptedException {
+ throws InterruptedException {
if (timeout > 0) {
long ms = toMillis(timeout);
int ns = excessNanos(timeout, ms);
@@ -278,17 +295,18 @@ public enum TimeUnit {
}
/**
- * Performs a timed Thread.join using this time unit.
+ * Performs a timed {@link Thread#join(long, int) Thread.join}
+ * using this time unit.
* This is a convenience method that converts time arguments into the
- * form required by the Thread.join method.
+ * form required by the {@code Thread.join} method.
+ *
* @param thread the thread to wait for
* @param timeout the maximum time to wait. If less than
* or equal to zero, do not wait at all.
- * @throws InterruptedException if interrupted while waiting.
- * @see Thread#join(long, int)
+ * @throws InterruptedException if interrupted while waiting
*/
public void timedJoin(Thread thread, long timeout)
- throws InterruptedException {
+ throws InterruptedException {
if (timeout > 0) {
long ms = toMillis(timeout);
int ns = excessNanos(timeout, ms);
@@ -297,13 +315,14 @@ public enum TimeUnit {
}
/**
- * Performs a Thread.sleep using this unit.
+ * Performs a {@link Thread#sleep(long, int) Thread.sleep} using
+ * this time unit.
* This is a convenience method that converts time arguments into the
- * form required by the Thread.sleep method.
+ * form required by the {@code Thread.sleep} method.
+ *
* @param timeout the minimum time to sleep. If less than
* or equal to zero, do not sleep at all.
- * @throws InterruptedException if interrupted while sleeping.
- * @see Thread#sleep
+ * @throws InterruptedException if interrupted while sleeping
*/
public void sleep(long timeout) throws InterruptedException {
if (timeout > 0) {