--- jsr166/src/jsr166e/LongAdderTable.java 2011/09/10 01:38:28 1.5 +++ jsr166/src/jsr166e/LongAdderTable.java 2012/08/13 15:52:33 1.9 @@ -12,10 +12,10 @@ import java.io.Serializable; /** * A keyed table of adders, that may be useful in computing frequency - * counts and histograms, or may be used a form of multiset. A {@link - * LongAdder} is associated with each key. Keys are added to the table - * implicitly upon any attempt to update, or may be added explicitly - * using method {@link #install}. + * counts and histograms, or may be used as a form of multiset. A + * {@link LongAdder} is associated with each key. Keys are added to + * the table implicitly upon any attempt to update, or may be added + * explicitly using method {@link #install}. * *

jsr166e note: This class is targeted to be placed in * java.util.concurrent.atomic @@ -31,8 +31,8 @@ public class LongAdderTable implement private final ConcurrentHashMapV8 map; static final class CreateAdder - implements ConcurrentHashMapV8.MappingFunction { - public LongAdder map(Object unused) { return new LongAdder(); } + implements ConcurrentHashMapV8.Fun { + public LongAdder apply(Object unused) { return new LongAdder(); } } private static final CreateAdder createAdder = new CreateAdder(); @@ -53,13 +53,7 @@ public class LongAdderTable implement * @return the adder associated with the key */ public LongAdder install(K key) { - LongAdder a = map.get(key); - if (a == null) { - LongAdder r = new LongAdder(); - if ((a = map.putIfAbsent(key, r)) == null) - a = r; - } - return a; + return map.computeIfAbsent(key, createAdder); } /** @@ -71,10 +65,7 @@ public class LongAdderTable implement * @param x the value to add */ public void add(K key, long x) { - LongAdder a = map.get(key); - if (a == null) - a = map.computeIfAbsent(key, createAdder); - a.add(x); + map.computeIfAbsent(key, createAdder).add(x); } /** @@ -136,7 +127,7 @@ public class LongAdderTable implement /** * Returns the sum totalled across all keys. * - * @return the sum totalled across all keys. + * @return the sum totalled across all keys */ public long sumAll() { long sum = 0L; @@ -156,7 +147,7 @@ public class LongAdderTable implement /** * Totals, then resets, the sums associated with all keys. * - * @return the sum totalled across all keys. + * @return the sum totalled across all keys */ public long sumThenResetAll() { long sum = 0L;