This is my doc for MinJreToolkit besides its javadoc. I don't know where to put it in wiki, so I post it here. Thanks for Regis's mentoring & all in the list that have ever helped me!
-Daniel On Mon, Aug 17, 2009 at 10:59 PM, Daniel Gong <daniel.gong.fu...@gmail.com>wrote: > *Introduction to MinJreToolkit* > > > > Version 0.01 > > > > 1. Main goal > > The main goal of MinJreToolkit is to implement a set of tools to help > developers decide which files of a JRE are necessary to execute a certain > custom JAVA application and then reduce the JRE size as much as possible to > just suit the custom application. > > > > 2. General idea > > The general idea of MinJreToolkit is to implement tools to automatically > analyze the custom application in several different ways and define a > uniformed result format which can be merged easily for all these tools. The > analyzing strategies include constant pool parsing, dynamic tracing and so > on. > > Due to the possible dynamic behavior of JAVA application, it is hard to > strictly decide the exact necessary files given a JRE implementation and a > JAVA application. Therefore, the task of the MinJreToolkit is to reduce the > JRE to a size which will be very possibly larger than the real minimum size > a bit. > > > > 3. Detailed design > > In the current version of MinJreToolkit, the basic result format has been > defined, associated with a class which contains the data of result and the > operations between results. Besides, two analyzing strategies and a JRE > generator have been implemented to perform static and dynamic analysis to a > custom application and generate a new JRE from an origin one according to > the final merged result. > > The basic result format > > The current result file is a plain text file with a cns file name > extension, called CNS (Class Name Set) file. The format of CNS file is > simple. It must start with a line of “Class Name Set File” and followed by a > list of fully qualified class name (such as java.io.File) or package name > (such as java.lang.*), only one item in a line without any empty characters > before and after the name. Empty lines are allowed between name lines for > that sometimes the user may want to organize the names in groups. > > The associated class, called ClassNameSet, is the data structure that > contains and manages the class name set. It can be initialized from a cns > file and can also be output to a cns file. More, it can merge from a cns > file or another instance of ClassNameSet. When trying to add a class name or > a package name, the instance of ClassNameSet will examine the name to decide > whether it is a valid name. If not, it will ignore it quietly and continue. > The future version of MinJreToolkit may add this kind of exception > information to a log file. > > Static analysis > > The static analysis is implemented based on bcel 5.2. The analyzer parses > the constant pool of each class with bcel, get the dependence between > classes and employ a simple dependency closure algorithm to calculate the > closure. The output of this analyzer is a cns file containing JRE classes in > the closure. > > Dynamic analysis > > The dynamic analysis is implemented as a JVMTI agent. It parses all the > class load events taking place in the runtime of an application and give a > cns file output. The agent is supposed to be used in tests. The coverage of > this kind of dynamic tracing depends on the coverage of test cases. > > JRE Generator > > The JRE generator should be initialized by a cns file which contains the > necessary classes that a certain JRE implementation must load in any case. > Then cns files can be added to the generator. After that, the generator copy > necessary files and “reduced” jar files to the target JRE directory. > > > > 4. What can you do with the demo > > Currently the demo contains > > > - the functional module of static analyzer and JRE generator > - the main class of static analyzer and JRE generator > - the command line scripts of static analyzer and JRE generator (in > Windows environment) > - the Ant task of static analyzer and JRE generator > - the dynamic tracing agent (in both Windows & Linux environment) > > A build.xml file has been provided to compile, test both command line > version and Ant task version of static analyzer and JRE generator as well as > the dynamic tracing agent and finally create the distribution of > MinJreToolkit including binary files, command line scripts and > documentation. > > To execute the build.xml file, the user should have Apache Ant installed > and well configured. Before the execution, the property of “jdk.dir”, > “origin.dir”, “target.dir” should be correctly configured to your JDK > directory, the original JRE directory and the target JRE directory > respectively. > > Run “ant” in the demo directory will execute the default target “dist” and > get a distribution of MinJreToolkit in the “dist” directory after compiling > and testing. After that, the user can use the distribution to help him/her > get a reduced JRE for his/her own application. > > Run “ant clean” in the demo directory will clean all files possibly > produced in the previous building process and restore the demo directory to > the original status. > > 5. Future plan > > Currently the following improvements are in the future plan: > > > - Optimize the closure calculation algorithm used in the static > analysis > - Reduce the output closure size > - Enhance the performance of the algorithm in speed and memory > occupancy > - Add other analyzers to make the toolkit generate smaller JRE > - Add a log functional module to the toolkit to provide more > information to user > > > On Mon, Aug 17, 2009 at 9:53 AM, Regis <xu.re...@gmail.com> wrote: > >> Daniel Gong wrote: >> >> >>> Since adding this is a small change, should I upload a new version to >>> JIRA? >>> >> >> I have committed the code to >> https://svn.apache.org/repos/asf/harmony/enhanced/tools/trunk/minijre at >> r804821 >> >> so you can create patch against it. >> >> >>> Besides, I am wondering what else should I do for GSoC? >>> >> >> It would be great if you can add a wiki page to introduce this tool. >> >> >>> -Daniel >>> >>> >> >> >> -- >> Best Regards, >> Regis. >> > >
