AspectJ 1.9.0
© Copyright 2018 Contributors. All rights reserved.
The full list of resolved issues in 1.9.0 is available here
Release info: 1.9.0 available 2-Apr-2018
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 class names and class-loading 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$preClinitmethod (where the factory invocation code is generated). Please provide feedback if this happens to you!
In anticipation of not all build plugins supporting that
-Xajruntimetarget option, you can now specify these kinds of option in
the ASPECTJ_OPTS environment variable. Set that in your environment:
export ASPECTJ_OPTS="-Xajruntimetarget:1.9"And it should get picked up by AspectJ when it runs.
AspectJ 1.9.0.RC4
Release info: 1.9.0.RC4 available 21-Feb-2018
Primary changes in RC4 are to add support for <compilerArg> in the Ant
task. This enables users of the Ant task to pass in options supported by
the underlying AspectJ but not yet surfaced elsewhere. Particularly
useful with Java9 which includes a number of module related commands.
For example, here is an iajc usage with compilerArg that is passing
--add-modules java.xml.bind:
<iajc destdir="bin" failonerror="true"
showWeaveInfo="true" source="1.9" target="1.9"
debug="true" fork="true" maxmem="256m">
<compilerArg value="--add-modules"/>
<compilerArg value="java.xml.bind"/>
<src path="src" />
<classpath>
<pathelement location="${aspectj.home}/lib/aspectjrt.jar"/>
</classpath>
</iajc>AspectJ 1.9.0.RC3
Release info: 1.9.0.RC3 available 5-Feb-2018
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.
AspectJ 1.9.0.RC2
Release info: 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
Release info: 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 automaticAnd 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.jarNow we have a demo module we can run:
$ java --module-path <pathto>/aspectjrt.jar:demo.jar --module demo/pkg.Demo
Azpect running
Demo runningThat’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.jarNotice 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 runningFaster Spring AOP
Dave Syer recently created a series of benchmarks for checking the speed of Spring-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/opSo 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/opLook 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.javafiles. 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. (Issue 526244) -
Related to that AspectJ, on detection of aspects should be able to automatically introduce the
requires org.aspectj.runtimeto the module-info. (Issue 526242) -
Module-aware variants of AspectJ paths:
--module-inpath,--module-aspectpath. (Issue 526243)