1 |
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN"> |
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN"> |
2 |
<html> |
<html> |
3 |
<head> |
<head> |
4 |
<title>JSR 166 Community Review Draft Introduction.</title> |
<title>JSR 166 Introduction.</title> |
5 |
</head> |
</head> |
6 |
|
|
7 |
<body bgcolor="#ffffee" vlink="#0000aa" link="#cc0000"> |
<body bgcolor="#ffffee" vlink="#0000aa" link="#cc0000"> |
8 |
<h1>JJSR 166 Community Review Draft Introduction.</h1> |
<h1>JSR 166 Introduction.</h1> |
9 |
|
|
10 |
by <a href="http://gee.cs.oswego.edu/dl">Doug Lea</a> |
by <a href="http://gee.cs.oswego.edu/dl">Doug Lea</a> |
11 |
<p> |
<p> |
12 |
|
|
13 |
To chack for updates to this draft, access a preliminary prototype |
This is the updated JSR166 specification. For further information, go |
14 |
release of main functionality, or join a mailing list discussing this |
to: <A |
|
JSR, go to: <A |
|
15 |
HREF="http://altair.cs.oswego.edu/mailman/listinfo/concurrency-interest"> |
HREF="http://altair.cs.oswego.edu/mailman/listinfo/concurrency-interest"> |
16 |
http://altair.cs.oswego.edu/mailman/listinfo/concurrency-interest</A> |
http://altair.cs.oswego.edu/mailman/listinfo/concurrency-interest</A>. |
17 |
. |
|
18 |
<p> |
<p><em>Note: The javadocs here includes some existing java.util |
19 |
|
Collection interfaces and classes that are not part of the JSR-166 |
20 |
<em> <b>Disclaimer</b>. The prototype implementation is experimental |
spec, but are included because JSR-166 methods implement or inherit |
21 |
code developed as part of JCP JSR-166 is made available to the |
from their specifications.</em> |
|
developer community for use as-is. It is not a supported product. Use |
|
|
it at your own risk. The specification, language and implementation |
|
|
are subject to change as a result of your feedback. Because these |
|
|
features have not yet been approved for addition to the Java language, |
|
|
there is no schedule for their inclusion in a product. </em> |
|
|
|
|
|
<p> <em> <b>Disclaimer</b>. This draft specification was produced |
|
|
using JDK1.4 tools plus some preprocessing. The resulting javadocs do |
|
|
not yet correctly render other planned JDK1.5 constructs on which |
|
|
JSR-166 relies, most notably the use of generic types. We are |
|
|
releasing this version now (before the availability of JDK1.5-based |
|
|
tools) because, even though they are misformatted and sometimes lack |
|
|
proper cross-referencing, they otherwise convey the intended |
|
|
specifications. </em> |
|
22 |
|
|
23 |
<p> JSR-166 introduces package <tt>java.util.concurrent</tt> |
<p> JSR-166 introduces package <tt>java.util.concurrent</tt> |
24 |
containing utility classes commonly useful in concurrent |
containing utility classes commonly useful in concurrent |
25 |
programming. Like package <tt>java.util</tt>, it includes a few small |
programming. Like package <tt>java.util</tt>, it includes a few small |
26 |
standardized extensible frameworks, as well as some classes that |
standardized extensible frameworks, as well as other classes that |
27 |
provide useful functionality and are otherwise tedious or difficult to |
provide useful functionality and are otherwise tedious or difficult to |
28 |
implement. |
implement. |
29 |
|
|
35 |
pools. This diversity reflects the range of contexts in which |
pools. This diversity reflects the range of contexts in which |
36 |
developers of concurrent programs have been found to require or desire |
developers of concurrent programs have been found to require or desire |
37 |
support not previously available in J2SE, which also keeping the |
support not previously available in J2SE, which also keeping the |
38 |
resulting package small; providing only that minimial support for |
resulting package small; providing only functionality that has been |
39 |
which it makes sense to standardize. |
found to be worthwhile to standardize. |
40 |
|
|
41 |
<p>Descriptions and brief motivations for the main components may be |
<p>Descriptions and brief motivations for the main components may be |
42 |
found in the associated package documentation. JSR-166 also includes |
found in the associated package documentation. JSR-166 also includes |
53 |
|
|
54 |
<h2>Threads</h2> |
<h2>Threads</h2> |
55 |
|
|
56 |
Two minor changes are introduced to the {@link java.lang.Thread} |
Three minor changes are introduced to the {@link java.lang.Thread} |
57 |
class: It now allows per-thread installation of handlers for uncaught |
class: |
58 |
exceptions. Ths optionally disassociates handlers from ThreadGroups, |
<ul> |
59 |
which has proven to be too inflexible. (Note that the combination of |
<li> It now allows per-thread installation of handlers for uncaught |
60 |
features in JSR-166 make ThreadGroups even less likely to be used in |
exceptions. Ths optionally disassociates handlers from ThreadGroups, |
61 |
most programs. Perhaps they will eventually be deprecated.) Secondly, |
which has proven to be too inflexible. (Note that the combination of |
62 |
access checks are no longer required when a Thread interrupts |
features in JSR-166 make ThreadGroups even less likely to be used in |
63 |
<em>itself</em>. The <tt>interrupt</tt> method is the only way to |
most programs. Perhaps they will eventually be deprecated.) |
64 |
re-assert a thread's interruption status (and in the case of |
|
65 |
self-interruption has no other effect than this). The check here |
<li> Access checks are no longer required when a Thread interrupts |
66 |
previously caused unjustifiable and uncontrollable failures when |
<em>itself</em>. The <tt>interrupt</tt> method is the only way to |
67 |
restricted code invoked library code that must reassert interruption |
re-assert a thread's interruption status (and in the case of |
68 |
to correctly propagate status when encountering some |
self-interruption has no other effect than this). The check here |
69 |
<tt>InterruptedExceptions</tt>. |
previously caused unjustifiable and uncontrollable failures when |
70 |
|
restricted code invoked library code that must reassert interruption |
71 |
|
to correctly propagate status when encountering some |
72 |
|
<tt>InterruptedExceptions</tt>. |
73 |
|
<li> The <tt>destroy</tt> method, which has never been implemented, |
74 |
|
has finally been deprecated. This is just a spec change, reflecting |
75 |
|
the fact that that the reason it has never been implemented is that |
76 |
|
it was undesirable and unworkable. |
77 |
|
</ul> |
78 |
|
|
79 |
<h2>Timing</h2> |
<h2>Timing</h2> |
80 |
|
|
91 |
|
|
92 |
|
|
93 |
<hr> |
<hr> |
|
<address><A HREF="http://gee.cs.oswego.edu/dl">Doug Lea</A></address> |
|
94 |
</body> |
</body> |
95 |
</html> |
</html> |