--- jsr166/src/test/loops/BinaryAsyncAction.java 2012/10/21 06:14:12 1.6 +++ jsr166/src/test/loops/BinaryAsyncAction.java 2015/09/14 16:47:43 1.20 @@ -13,13 +13,13 @@ import java.util.concurrent.atomic.*; * have smaller stack space footprints and faster completion mechanics * but higher per-task footprints. Compared to LinkedAsyncActions, * BinaryAsyncActions are simpler to use and have less overhead in - * typical uasges but are restricted to binary computation trees. + * typical usages but are restricted to binary computation trees. * - *
Upon construction, an BinaryAsyncAction does not bear any + *
Upon construction, a BinaryAsyncAction does not bear any * linkages. For non-root tasks, links must be established using - * method linkSubtasks before use. + * method {@link #linkSubtasks} before use. * - *
Sample Usage. A version of Fibonacci: + *
Sample Usage. A version of Fibonacci: *
* class Fib extends BinaryAsyncAction { * final int n; @@ -27,28 +27,28 @@ import java.util.concurrent.atomic.*; * Fib(int n) { this.n = n; } * protected void compute() { * if (n > 1) { - * linkAndForkSubtasks(new Fib(n-1), new Fib(n-2)); + * linkAndForkSubtasks(new Fib(n-1), new Fib(n-2)); * else { - * result = n; // fib(0)==0; fib(1)==1 - * complete(); + * result = n; // fib(0)==0; fib(1)==1 + * complete(); * } * } * protected void onComplete(BinaryAsyncAction x, BinaryAsyncAction y) { - * result = ((Fib)x).result + ((Fib)y).result; + * result = ((Fib)x).result + ((Fib)y).result; * } * } *- * An alternative, and usually faster strategy is to instead use a + * An alternative, and usually faster, strategy is to instead use a * loop to fork subtasks: *
* protected void compute() { * Fib f = this; * while (f.n > 1) { - * Fib left = new Fib(f.n - 1); - * Fib right = new Fib(f.n - 2); - * f.linkSubtasks(left, right); - * right.fork(); // fork right - * f = left; // loop on left + * Fib left = new Fib(f.n - 1); + * Fib right = new Fib(f.n - 2); + * f.linkSubtasks(left, right); + * right.fork(); // fork right + * f = left; // loop on left * } * f.result = f.n; * f.complete(); @@ -75,7 +75,7 @@ public abstract class BinaryAsyncAction /** * Creates a new action. Unless this is a root task, you will need - * to link it using method linkSubtasks before forking as + * to link it using method {@link #linkSubtasks} before forking as * a subtask. */ protected BinaryAsyncAction() { @@ -89,7 +89,7 @@ public abstract class BinaryAsyncAction * as parent, and each other as siblings. * @param x one subtask * @param y the other subtask - * @throws NullPointerException if either argument is null. + * @throws NullPointerException if either argument is null */ public final void linkSubtasks(BinaryAsyncAction x, BinaryAsyncAction y) { x.parent = y.parent = this; @@ -98,9 +98,9 @@ public abstract class BinaryAsyncAction } /** - * Overridable callback action triggered upon complete of + * Overridable callback action triggered upon {@code complete} of * subtasks. Upon invocation, both subtasks have completed. - * After return, this task isDone and is joinable by + * After return, this task {@code isDone} and is joinable by * other tasks. The default version of this method does nothing. * But it may be overridden in subclasses to perform some action * (for example a reduction) when this task is completes. @@ -112,22 +112,22 @@ public abstract class BinaryAsyncAction /** * Overridable callback action triggered by - * completeExceptionally. Upon invocation, this task has + * {@code completeExceptionally}. Upon invocation, this task has * aborted due to an exception (accessible via - * getException). If this method returns true, + * {@code getException}). If this method returns {@code true}, * the exception propagates to the current task's * parent. Otherwise, normal completion is propagated. The * default version of this method does nothing and returns - * true. + * {@code true}. * @return true if this task's exception should be propagated to - * this tasks parent. + * this task's parent */ protected boolean onException() { return true; } /** - * Equivalent in effect to invoking linkSubtasks and then + * Equivalent in effect to invoking {@link #linkSubtasks} and then * forking both tasks. * @param x one subtask * @param y the other subtask @@ -156,9 +156,9 @@ public abstract class BinaryAsyncAction /** * Completes this task, and if this task has a sibling that is - * also complete, invokes onComplete of parent task, and so + * also complete, invokes {@code onComplete} of parent task, and so * on. If an exception is encountered, tasks instead - * completeExceptionally. + * {@code completeExceptionally}. */ public final void complete() { // todo: Use tryUnfork without possibly blowing stack @@ -169,7 +169,7 @@ public abstract class BinaryAsyncAction a.sibling = null; a.parent = null; a.completeThis(); - if (p == null || p.compareAndSetControlState(0, 1)) + if (p == null || p.compareAndSetControlState(0, 1)) break; try { p.onComplete(a, s); @@ -184,15 +184,15 @@ public abstract class BinaryAsyncAction /** * Completes this task abnormally. Unless this task already * cancelled or aborted, upon invocation, this method invokes - * onException, and then, depending on its return value, - * completees parent (if one exists) exceptionally or normally. To + * {@code onException}, and then, depending on its return value, + * completes parent (if one exists) exceptionally or normally. To * avoid unbounded exception loops, this method aborts if an - * exception is encountered in any onException + * exception is encountered in any {@code onException} * invocation. * @param ex the exception to throw when joining this task * @throws NullPointerException if ex is null * @throws Throwable if any invocation of - * onException does so. + * {@code onException} does so */ public final void completeExceptionally(Throwable ex) { BinaryAsyncAction a = this; @@ -209,7 +209,7 @@ public abstract class BinaryAsyncAction /** * Returns this task's parent, or null if none or this task * is already complete. - * @return this task's parent, or null if none. + * @return this task's parent, or null if none */ public final BinaryAsyncAction getParent() { return parent; @@ -218,7 +218,7 @@ public abstract class BinaryAsyncAction /** * Returns this task's sibling, or null if none or this task is * already complete. - * @return this task's sibling, or null if none. + * @return this task's sibling, or null if none */ public BinaryAsyncAction getSibling() { return sibling; @@ -267,7 +267,7 @@ public abstract class BinaryAsyncAction } /** - * Sets the control state to the given value, + * Increments the control state. * @param value the new value */ protected final void incrementControlState() { @@ -275,11 +275,10 @@ public abstract class BinaryAsyncAction } /** - * Decrement the control state + * Decrements the control state. * @return true if successful */ protected final void decrementControlState() { controlStateUpdater.decrementAndGet(this); } - }