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author | Alexander Kriegisch <Alexander@Kriegisch.name> | 2021-06-29 13:18:25 +0700 |
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committer | Alexander Kriegisch <Alexander@Kriegisch.name> | 2024-01-06 10:09:11 +0100 |
commit | ebbc41255384e85db03c4eb6aae4e6464803d0a9 (patch) | |
tree | 4d90f6d206ec43bef21eb601161785c4502d358e /docs/dist/doc/README-190.adoc | |
parent | 0ba9f25b0e5deb638f6e7472141f4edc4450c99b (diff) | |
download | aspectj-ebbc41255384e85db03c4eb6aae4e6464803d0a9.tar.gz aspectj-ebbc41255384e85db03c4eb6aae4e6464803d0a9.zip |
Add initial set of AsciiDoc files, converted from HTML/XML
Some originals have been deleted already. Others, especially the user
guides, still exist in both formats because they have not been
proof-read and probably lots of links do not function as expected. But I
want to see what the files look like directly on GitHun.
Signed-off-by: Alexander Kriegisch <Alexander@Kriegisch.name>
Diffstat (limited to 'docs/dist/doc/README-190.adoc')
-rw-r--r-- | docs/dist/doc/README-190.adoc | 339 |
1 files changed, 339 insertions, 0 deletions
diff --git a/docs/dist/doc/README-190.adoc b/docs/dist/doc/README-190.adoc new file mode 100644 index 000000000..3b1f27784 --- /dev/null +++ b/docs/dist/doc/README-190.adoc @@ -0,0 +1,339 @@ +[.small]#© Copyright 2018 Contributors. All rights reserved.# + +The full list of resolved issues in 1.9.0 is available +https://bugs.eclipse.org/bugs/buglist.cgi?bug_status=RESOLVED&bug_status=VERIFIED&bug_status=CLOSED&f0=OP&f1=OP&f3=CP&f4=CP&j1=OR&list_id=16866879&product=AspectJ&query_format=advanced&target_milestone=1.9.0[here] + +. + +== AspectJ 1.9.0 + +=== Improved runtime interface + +New factory methods have been added to the AspectJ runtime. This is an +attempt to more optimally create thisJoinPoint and +thisEnclosingJoinPoint objects. The generated code that invokes these +now also uses the ability for the LDC bytecode instruction to load class +constants directly (this replaces what was happening previously where +generated code referenced string classnames and classloading was being +done from the aspectj runtime as the woven application was starting). + +This is turned on by using -Xajruntimetarget:1.9. This option was used +previously to enable users to target an old runtime if they knew that +old runtime is all that was available at some deployed target. The new +generation mechanism is not the default, not until it has had a bit more +testing out in the wild. + +The changes to generated code have a couple of potential side effects: + +* *overall size*: the woven code may be smaller due to the use of +smaller string constant pieces in the generated code (previously strings +were smashed together in the generated code and then taken apart by +AspectJ at runtime). Since the pieces are smaller, they can be shared +across other uses in the class file. +* *method size*: although the overall class may be smaller there are +more instructions involved in preparing the data for invocation of the +new joinpoint factory methods. It is possible if you have a lot of +joinpoints that we might blow the 64k instruction limit for the +ajc$preClinit method (where the factory invocation code is generated). +Please provide feedback if this happens to you! + +In anticipation of not all build plugins supporting that +-Xajruntimetarget option, you can now specify these kinds of option in +the ASPECTJ_OPTS environment variable. Set that in your environment: + +.... +export ASPECTJ_OPTS="-Xajruntimetarget:1.9" +.... + +And it should get picked up by AspectJ when it runs. + +* 1.9.0 available 2-Apr-2018 + +== AspectJ 1.9.0.RC4 + +Primary changes in RC4 are to add support for <compilerArg> in the Ant +task. This enables users of the Ant task to pass in options supported by +the underlying AspectJ but not yet surfaced elsewhere. Particularly +useful with Java9 which includes a number of module related commands. +For example, here is an iajc usage with compilerArg that is passing +--add-modules java.xml.bind: + +.... + <iajc destdir="bin" failonerror="true" + showWeaveInfo="true" source="1.9" target="1.9" + debug="true" fork="true" maxmem="256m"> + <compilerArg value="--add-modules"/> + <compilerArg value="java.xml.bind"/> + <src path="src" /> + <classpath> + <pathelement location="${aspectj.home}/lib/aspectjrt.jar"/> + </classpath> + </iajc> +.... + +1.9.0.RC4 available 21-Feb-2018 + +== AspectJ 1.9.0.RC3 + +Primary changes in RC3 are to upgrade JDT and pickup all the fixes for +Java9 that have gone into it over the last few months. + +1.9.0.RC3 available 5-Feb-2018 + +== AspectJ 1.9.0.RC2 + +* 1.9.0.RC2 available 9-Nov-2017 + +Key change in 1.9.0.RC2 is actually to be more tolerant of JDK10. The +version handling has been somewhat overhauled so AspectJ 9 will behave +better on Java 10 and future JDKs. This should put AspectJ in a better +place if new JDK versions are going to arrive thick and fast. + +== AspectJ 1.9.0.RC1 + +* 1.9.0.RC1 available 20-Oct-2017 + +This is the first release candidate of AspectJ 1.9.0 - the version of +AspectJ to be based on Java9. It includes a recent version of the +Eclipse Java9 compiler (from jdt core, commit #062ac5d7a6bf9). + +=== Automatic Modules + +AspectJ can now be used with the new module system available in Java9. +The key jars in AspectJ have been given automatic module names. The +automatic module name is org.aspectj.runtime for the aspectjrt module: + +.... +$ java --module-path <pathto>/lib/aspectjrt.jar --list-modules | grep aspectj + +org.aspectj.runtime file:///<pathto>/lib/aspectjrt.jar automatic +.... + +And similarly org.aspectj.weaver and org.aspectj.tools for aspectjweaver +and aspectjtools respectively: + +.... +$ java --module-path <pathto>/lib/aspectjweaver.jar --describe-module org.aspectj.weaver + +org.aspectj.weaver file:///<pathto>/lib/aspectjweaver.jar automatic +requires java.base mandated +contains aj.org.objectweb.asm +contains aj.org.objectweb.asm.signature +contains org.aspectj.apache.bcel +contains org.aspectj.apache.bcel.classfile +contains org.aspectj.apache.bcel.classfile.annotation +contains org.aspectj.apache.bcel.generic +contains org.aspectj.apache.bcel.util +contains org.aspectj.asm +contains org.aspectj.asm.internal +... +.... + + + + + + +=== Building woven modules + +AspectJ understands module-info.java source files and building modules +that include aspects. Here is an example: + +.... +module-info.java + +module demo { + exports pkg; + requires org.aspectj.runtime; +} + + +pkg/Demo.java + +package pkg; + +public class Demo { + public static void main(String[] argv) { + System.out.println("Demo running"); + } +} + + +otherpkg/Azpect.java + +package otherpkg; + +public aspect Azpect { + before(): execution(* *(..)) && !within(Azpect) { + System.out.println("Azpect running"); + } +} +.... + +We can now build those into a module: + +.... +$ ajc -1.9 module-info.java otherpkg/Azpect.java pkg/Demo.java -outjar demo.jar + +... +module-info.java:3 [error] org.aspectj.runtime cannot be resolved to a module +... +.... + +Wait, that failed! Yes, aspectjrt.jar (which includes the required +org.aspectj.weaver module) wasn't supplied. We need to pass it on the +module-path: + +.... +$ ajc -1.9 --module-path <pathto>/aspectjrt.jar module-info.java otherpkg/Azpect.java pkg/Demo.java -outjar demo.jar +.... + +Now we have a demo module we can run: + +.... +$ java --module-path <pathto>/aspectjrt.jar:demo.jar --module demo/pkg.Demo + +Azpect running +Demo running +.... + +That's it! + + + + + + +=== Binary weaving with modules + +A module is really just a jar with a module-info descriptor. As such you +can simply pass a module on the inpath and binary weave it with other +aspects. Take the module we built above, let's weave into it again: + +.... +extra/AnotherAzpect.java + +package extra; + +public aspect AnotherAzpect { + before(): execution(* *(..)) && !within(*Azpect) { + System.out.println("AnotherAzpect running"); + } +} +.... + +.... +$ ajc -inpath demo.jar AnotherAzpect.java -outjar newdemo.jar +.... + +Notice how there was no complaint here that the org.aspectj.runtime +module hadn't been passed in. That is because inpath was being used +which doesn't treat specified jars as modules (and so does not check +dependencies). There is no module-inpath right now. + +Because the new jar produced includes the compiled aspect, the +module-info specification inside is still correct, so we can run it +exactly as before: + +.... +$ java --module-path ~/installs/aspectj190rc1/lib/aspectjrt.jar:newdemo.jar --module demo/pkg.Demo + +Azpect running +AnotherAzpect running +Demo running +.... + + + + + + +=== Faster Spring AOP + +Dave Syer recently created a series of benchmarks for checking the speed +of Spring-AspectJ: https://github.com/dsyer/spring-boot-aspectj + +Here we can see the numbers for AspectJ 1.8.11 (on an older Macbook +Pro): + +.... +Benchmark (scale) Mode Cnt Score Error Units +StartupBenchmark.ltw N/A avgt 10 2.553 ~ 0.030 s/op +StartupBenchmark.ltw_100 N/A avgt 10 2.608 ~ 0.046 s/op +StartupBenchmark.spring v0_10 avgt 10 2.120 ~ 0.148 s/op +StartupBenchmark.spring v1_10 avgt 10 2.219 ~ 0.066 s/op +StartupBenchmark.spring v1_100 avgt 10 2.244 ~ 0.030 s/op +StartupBenchmark.spring v10_50 avgt 10 2.950 ~ 0.026 s/op +StartupBenchmark.spring v20_50 avgt 10 3.854 ~ 0.090 s/op +StartupBenchmark.spring v20_100 avgt 10 4.003 ~ 0.038 s/op +StartupBenchmark.spring a0_10 avgt 10 2.067 ~ 0.019 s/op +StartupBenchmark.spring a1_10 avgt 10 2.724 ~ 0.023 s/op +StartupBenchmark.spring a1_100 avgt 10 2.778 ~ 0.057 s/op +StartupBenchmark.spring a10_50 avgt 10 7.191 ~ 0.134 s/op +StartupBenchmark.spring a10_100 avgt 10 7.191 ~ 0.168 s/op +StartupBenchmark.spring a20_50 avgt 10 11.541 ~ 0.158 s/op +StartupBenchmark.spring a20_100 avgt 10 11.464 ~ 0.157 s/op +.... + +So this is the average startup of an app affected by aspects applying to +the beans involved. Where numbers are referenced the first is the number +of aspects/pointcuts and the second is the number of beans. The 'a' +indicates an annotation based pointcut vs a non-annotation based +pointcut ('v'). Notice things are much worse for annotation based +pointcuts. At 20 pointcuts and 50 beans the app is 9 seconds slower to +startup. + + +In AspectJ 1.8.12 and 1.9.0.RC1 some work has been done here. The key +change is to recognize that the use of annotations with runtime +retention is much more likely than annotations with class level +retention. Retrieving annotations with class retention is costly because +we must open the bytes for the class file and dig around in there (vs +runtime retention which are immediately accessible by reflection on the +types). In 1.8.11 the actual type of the annotation involved in the +matching is ignored and the code will fetch *all* the annotations on the +type/method/field being matched against. So even if the match is looking +for a runtime retention annotation, we were doing the costly thing of +fetching any class retention annotations. In 1.8.12/1.9.0.RC1 we take +the type of the match annotation into account - allowing us to skip +opening the classfiles in many cases. There is also some deeper work on +activating caches that were not previously being used correctly but the +primary change is factoring in the annotation type. + +What difference does that make? AspectJ 1.9.0.RC1: + +.... +Benchmark (scale) Mode Cnt Score Error Units +StartupBenchmark.ltw N/A avgt 10 2.568 ~ 0.035 s/op +StartupBenchmark.ltw_100 N/A avgt 10 2.622 ~ 0.075 s/op +StartupBenchmark.spring v0_10 avgt 10 2.096 ~ 0.054 s/op +StartupBenchmark.spring v1_10 avgt 10 2.206 ~ 0.031 s/op +StartupBenchmark.spring v1_100 avgt 10 2.252 ~ 0.025 s/op +StartupBenchmark.spring v10_50 avgt 10 2.979 ~ 0.071 s/op +StartupBenchmark.spring v20_50 avgt 10 3.851 ~ 0.058 s/op +StartupBenchmark.spring v20_100 avgt 10 4.000 ~ 0.046 s/op +StartupBenchmark.spring a0_10 avgt 10 2.071 ~ 0.026 s/op +StartupBenchmark.spring a1_10 avgt 10 2.182 ~ 0.032 s/op +StartupBenchmark.spring a1_100 avgt 10 2.272 ~ 0.024 s/op +StartupBenchmark.spring a10_50 avgt 10 2.557 ~ 0.027 s/op +StartupBenchmark.spring a10_100 avgt 10 2.598 ~ 0.040 s/op +StartupBenchmark.spring a20_50 avgt 10 2.961 ~ 0.043 s/op +StartupBenchmark.spring a20_100 avgt 10 3.093 ~ 0.098 s/op +.... + +Look at the a20_100 case - instead of impacting start time by 9 seconds, +it impacts it by 1 second. + +=== More to come... + +* Eclipse JDT Java 9 support is still being actively worked on and lots +of fixes will be coming through over the next few months and included in +AspectJ 1.9.X revisions. +* AspectJ does not currently modify module-info.java files. An aspect +from one module applying to code in another module clearly introduces a +dependency between those two modules. There is no reason - other than +time! - that this can't be done. +(https://bugs.eclipse.org/bugs/show_bug.cgi?id=526244[Issue 526244]) +* Related to that AspectJ, on detection of aspects should be able to +automatically introduce the requires org.aspectj.runtime to the +module-info. (https://bugs.eclipse.org/bugs/show_bug.cgi?id=526242[Issue +526242]) +* Module aware variants of AspectJ paths: --module-inpath, +--module-aspectpath. +(https://bugs.eclipse.org/bugs/show_bug.cgi?id=526243[Issue 526243]) + + + + + |