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diff --git a/docs/dist/doc/README-187.html b/docs/dist/doc/README-187.html new file mode 100644 index 000000000..1d9b28c24 --- /dev/null +++ b/docs/dist/doc/README-187.html @@ -0,0 +1,133 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> +<html> <head> +<title>AspectJ 1.8.7 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 2015 Contributors. +All rights reserved. +</small></div> + +<h1>AspectJ 1.8.7 Readme</h1> + +<p>The full list of resolved issues in 1.8.7 is available +<a href="https://bugs.eclipse.org/bugs/buglist.cgi?query_format=advanced;bug_status=RESOLVED;bug_status=VERIFIED;bug_status=CLOSED;product=AspectJ;target_milestone=1.8.7;">here</a></h2>.</p> + +<ul> +<li>1.8.7 available 9-Sep-2015 +</ul> + + +<h2>Notable changes</h2> + +<h3>ajdoc</h3> +<p>The ajdoc tool has been fixed! It is now working again if run on a 1.7 JDK.</p> + +<h3>Dynamic weaver attachment</h3> +<p>The AspectJ loadtime weaving agent can now be dynamically attached to a JVM after it has started +(you don't need to use -javaagent). This offers extra flexibility but obviously any +classes loaded before attachment will not be woven.</p> + +<p>Here is a simple aspect:</p> +<code><pre> +public aspect Azpect { + before(): execution(* *(..)) { + System.out.println(thisJoinPointStaticPart); + } +} +</pre></code> + +<p>Compiled via:</p> + +<code><pre>ajc -1.8 Azpect.java -outxml</pre></code> + +<p>This produces a compiled class <tt>Azpect.class</tt> and a file <tt>META-INF/aop-ajc.xml</tt>.</p> + +<p>I then have this sample application (same directory):</p> + +<code><pre> +import java.lang.management.ManagementFactory; +import org.aspectj.weaver.loadtime.Agent; +import com.sun.tools.attach.VirtualMachine; + +public class Application { + + public static void main(String[] args) { + if (!isAspectJAgentLoaded()) + System.err.println("WARNING: AspectJ weaving agent not loaded"); + new Sample().doSomething(); + } + + public static boolean isAspectJAgentLoaded() { + try { + Agent.getInstrumentation(); + } catch (NoClassDefFoundError e) { + System.out.println(e); + return false; + } catch (UnsupportedOperationException e) { + System.out.println(e); + return dynamicallyLoadAspectJAgent(); + } + return true; + } + + public static boolean dynamicallyLoadAspectJAgent() { + String nameOfRunningVM = ManagementFactory.getRuntimeMXBean().getName(); + int p = nameOfRunningVM.indexOf('@'); + String pid = nameOfRunningVM.substring(0, p); + try { + VirtualMachine vm = VirtualMachine.attach(pid); + String jarFilePath = System.getProperty("AGENT_PATH"); + vm.loadAgent(jarFilePath); + vm.detach(); + } catch (Exception e) { + System.out.println(e); + return false; + } + return true; + } +} +</pre></code> + +<p>And this Sample class:</p> +<code><pre> +public class Sample { + public void doSomething() { + System.out.println("Do something"); + System.out.println("Square of 7 = " + square(7)); + } + + private int square(int i) { + return i * i; + } +} +</pre></code> + +<p>Compile these with javac, <b>but you must have the aspectjweaver and the JDK tools.jar on your classpath</b>.</p> + +<p>Once compiled we can run it:</p> + +<code><pre>java -DAGENT_PATH=<path-to>/aspectjweaver.jar Application</pre></code> + +<p>What does it do? The main method calls the function that detects whether the agent is attached, if it is not then +it programmatically attaches it using the <tt>VirtualMachine</tt> class. Then the main method accesses the +Sample class. At this point in program execution the Sample class is loaded and because the agent has been +attached it gets woven. Notice that the <tt>Application</tt> class itself is not woven because it was loaded prior +to agent attachment.</p> + +<p>Thanks to Alexander Kriegisch for the sample code and the patch to add this behaviour to AspectJ.</p> + + +<!-- ============================== --> +</body> +</html> |