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diff --git a/docs/dist/doc/README-164.html b/docs/dist/doc/README-164.html deleted file mode 100644 index eadb5a8f5..000000000 --- a/docs/dist/doc/README-164.html +++ /dev/null @@ -1,204 +0,0 @@ -<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> -<html> <head> -<title>AspectJ 1.6.4 Readme</title> -<style type="text/css"> -<!-- - P { margin-left: 20px; } - PRE { margin-left: 20px; } - LI { margin-left: 20px; } - H4 { margin-left: 20px; } - H3 { margin-left: 10px; } ---> -</style> -</head> - -<body> -<div align="right"><small> -© Copyright 2009 Contributors. -All rights reserved. -</small></div> - -<h1>AspectJ 1.6.4 Readme</h1> - -<ul> -<li><a href="#compilation">Compilation times</a></li> -<li><a href="#language">Language enhancements</a></li> -<li><a href="#bugsfixed">Bugs fixed</a></li> -<li><a href="#whatsnext">What's next?</a></li> -</ul> -<hr> -<a name="compilation"/> -<H4>Compilation times</h4> -<p>In AspectJ 1.6.4 the goal was to improve the IDE experience, through a combination of improved compilation speed (both full -builds and incremental builds), improved support for multiple-project configurations, and improved feedback in the editor. The -following sections go into details on each of those topics.</p> - -<p><B>Full Compilation</b></p> -<p>As an example project, all the measurements here are based on the modified JDT compiler that AspectJ uses internally. It is -1100 source files and includes aspects that affect around 850 join points. Here are the full build times in AJDT: -</p> -<p>AJDT 1.6.3 (uses AspectJ 1.6.3)</p> -<code><pre> -21352ms -21597ms -21502ms -</pre></code> - -<p>AJDT 1.6.5dev builds (use AspectJ 1.6.4)</p> -<code><pre> -19811ms -19802ms -19504ms -</pre></code> -<p> -About 1.5-2 seconds faster for this example. -</p> -<p><b>Incremental Compilation and multi-project scenarios</b></p> -<p>In most common project configurations there are multiple eclipse projects in some kind of dependency hierarchy. Depending on -what changes in a top level project, those downstream may need to be rebuilt. The analysis around this area has greatly improved -in AspectJ 1.6.4, and this has resulted in much reduced incremental build times. The example timed here is around 20 AspectJ -projects in a hierarchy, and a change is made to a source file in the top level project and build times are observed for the -downstream projects.</p> -<p>The timings reported here are accessible to anyone with AJDT installed - just open the 'AJDT Event Trace View' and it will -report ongoing information about what the compiler/weaver and AJDT are up to. Be aware that data is only recorded in this view -if it is open - so for optimal performance it should be shutdown, but it is useful for debugging scenarios or collecting -basic benchmark numbers. Within the event trace view output, the time recorded for 'time spent in AJDE' represents the time -spent in the compiler: analysing what has changed on the classpath, building code, weaving code. -</p> -<p>Initially this is using AJDT 1.6.2 (which embeds AspectJ 1.6.3):</p> -<p> -<code><pre> -Type of change: adding a new method to a type -Project build times (first one is the compile of our change, the rest are for downstream projects): -462ms, 4ms, 145ms, 8ms, 9ms, 287ms, 471ms, 222ms, 1028ms, 143ms, 505ms, 199ms, 261ms, 1224ms, -321ms, 704ms, 75ms, 233ms, 257ms -Summary: Total time spent in the compiler for that change: <b>6558ms</b> ---- -Type of change: whitespace change (adding just a harmless space character) -Project build times (first one is the compile of our change, the rest are for downstream projects): -229ms, 5ms, 10ms, 9ms, 10ms, 79ms, 43ms, 62ms, 80ms, 37ms, 64ms, 32ms, 79ms, -154ms, 94ms, 189ms, 72ms, 144ms, 205ms -Summary: Total time spent in the compiler for that change: <b>1597ms</b> -</pre></code> -</p> -<p>Now with AspectJ 1.6.5 dev builds (which embed AspectJ 1.6.4):</p> -<p> -<code><pre> -Type of change: adding a new method to a type -Project build times (first one is the compile of our change, the rest are for downstream projects): -288ms, 3ms, 143ms, 2ms, 2ms, 162ms, 244ms, 89ms, 489ms, 113ms, 277ms, 108ms, 143ms, 626ms, -135ms, 260ms, 2ms, 96ms, 6ms -Summary: Total time spent in the compiler for that change: <b>3188ms</b> down from 6558ms - -Type of change: whitespace change (adding just a harmless space character) -Project build times (first one is the compile of our change, the rest are for downstream projects): -101ms, 1ms, 1ms, 1ms, 0ms, 1ms, 1ms, 1ms, 1ms, 1ms, 0ms, 1ms, 1ms, 2ms, 0ms, 1ms, 0ms, 2ms, 2ms -Summary: Total time spent in the compiler for that change: <b>118ms</b> (down from 1597ms) -</pre></code> -</p> -<p> -Improvements all round, and almost instant builds now for whitespace changes, even in large -project setups. -</p> -<p>In addition the compilation times are also improved in situations where AspectJ projects depend upon Java projects and -where aspectpath is used. AJDT 1.6.5 dev builds also include some changes that really speed up builds. -</p> -<h4>Better editor feedback</h4> -<p>Under <a href="https://bugs.eclipse.org/bugs/show_bug.cgi?id=246393">bug 246393</a> the problem has been addressed where -sometimes spurious errors would appear throughout the editor for a file in AJDT when just one single simple syntax errors exists. More -detail on this problem can be found -<a href="http://andrewclement.blogspot.com/2009/02/aspectj-fixing-reverse-cascade-errors.html">here</a>. -</p> -<hr> -<a name="language"/> -<H4>Language Enhancements</h4> -<p><b>Optimizing support for maintaining per join point state</b></p> -<p>The traditional way to maintain state on a per join point basis involves using the JoinPoint.StaticPart as a key -into a map: -<code><pre> -aspect X pertypewithin(*) { - Map<JoinPoint.StaticPart,Timer> timerMap = ... - - Object around(): execution(public * *(..)) { - Timer timerToUse = timerMap.get(thisJoinPointStaticPart); - timerToUse.start(); - Object o = proceed(); - timerToUse.stop(); - return o; - } -} -</pre></code> -<p>These map lookups are slow. In AspectJ 1.6.4 there is a new getId() method on the JoinPoint.StaticPart object. -The ids for all affected join points within a target type are unique (and start from 0) - they are ideal for -array lookups. So using this the above aspect can be rewritten: -</p> - -<code><pre> -aspect X pertypewithin(*) { - Timer[] timerArray = ... - - Object around(): execution(public * *(..)) { - Timer timerToUse = timerArray[thisJoinPointStaticPart.getId()]; - timerToUse.start(); - Object o = proceed(); - timerToUse.stop(); - return o; - } -} -</pre></code> -<p>much faster. Just be aware that the ids are only unique within an affected target type - hence the use of pertypewithin -in this example to ensure there is an aspect instance (and so a different array) for each advised type.</p> -<p>See related <a href="https://bugs.eclipse.org/bugs/show_bug.cgi?id=89009">bug 89009</a> for the full discussion</p> - -<h4>@DeclareMixin</h4> -<p>The annotation style declare parents support (@DeclareParents) has been (rightly) criticized because it really does not offer -an equivalent to what is possible with code style declare parents, it really offers a mixin strategy. It also has limitations -such as the delegate instance used to satisfy any method invocations on an affected target cannot access the object instance for -which it is acting as a delegate. To address these concerns a proper mixin notation has been introduced that makes it more clear -that a mixin strategy is being employed and it addresses the problem of the mixin delegate accessing the affected target instance. -</p> -<p> -The @DeclareMixin annotation is attached to a factory method which returns instances of the delegate. Here is a basic example: -</p> -<code><pre> - // The factory method that can build the delegate instance is annotated with @DeclareMixin. - // The annotation value defines the type pattern for targets of the mixin. - // The parameter is the object for which a delegate is being constructed. - // The interface that will be mixed in is the return value of the factory method. - @DeclareMixin("org.xyz..*") - public static SomeInterface createDelegate(Object instance) { - return new SomeImplementation(instance); - } -</pre></code> -<p>More examples are <a href="http://www.eclipse.org/aspectj/doc/released/adk15notebook/ataspectj-itds.html">here in the online -documentation</a>.</p> -<p>Going forward attempts will be made to try and make @DeclareParents behave more like code style - if this cannot -be done it is likely to be deprecated.</p> -<hr> -<a name="bugsfixed"/> -<h4>Bugs fixed</h4> -<p>The complete list of issues resolved for AspectJ 1.6.4 (more than 70) can be found with -this bugzilla query: -<ul> -<li><a href="https://bugs.eclipse.org/bugs/buglist.cgi?query_format=advanced&short_desc_type=allwordssubstr&short_desc=&product=AspectJ&target_milestone=1.6.4&long_desc_type=allwordssubstr&long_desc=&bug_file_loc_type=allwordssubstr&bug_file_loc=&status_whiteboard_type=allwordssubstr&status_whiteboard=&keywords_type=allwords&keywords=&bug_status=RESOLVED&bug_status=VERIFIED&bug_status=CLOSED&emailtype1=substring&email1=&emailtype2=substring&email2=&bugidtype=include&bug_id=&votes=&chfieldfrom=&chfieldto=Now&chfieldvalue=&cmdtype=doit&order=Reuse+same+sort+as+last+time&field0-0-0=noop&type0-0-0=noop&value0-0-0=">Bugs resolved</a> -</ul> -<hr> -<a name="whatsnext"/> -<h4>What's next?</h4> -<p><b>More incremental build enhancements</b></p> -<p>A number of situations still exist where incremental compile speeds still needs optimizing, particular when capabilities -like aspectpath or inpath are used.</p> -<p><b>Build state persistence</b></p> -<p>Between restarts of Eclipse the state of each project is not recorded - hence full builds are required upon restart. The -state (and associated relationship model) should be persisted between restarts, but both of these need a review first to ensure -they are not larger than they need to be. -</p> -<p><b>Memory consumption</b</p> -<p>Both for source compilation and load-time weaving scenarios. The size of the model in the IDE needs reviewing, and also the -type map within the weaver. Although the type map uses Weak/Soft references to try and better control how it uses memory, the JVM -policies for managing these references vary wildly and so some work needs to be done to allow for these differences. -<hr> - -<!-- ============================== --> -</body> -</html> |