Hi,
I am working on a project and I need to debug the Bytecode generated by a library. Reading the bytecode and trying to figure out where to the problem could be can be tedious at times.
Is there a Bytecode debugger that I can use to decompile the .class files and possibly execute them step-by-step?
Thanks
Junior interview focused on Java compiler and Java bytecode
Hey guys, I’m going to have a junior interview heavily focused on Java compiler and bytecode. I’m very comfortable and proficient with Java however I’m not so experienced with the compiler technologies and bytecode. Can someone point me some good resources for studying, reading and understanding better these technologies please?
Thank you!
Title says it all. Looking for the blog post. Was all around pretty ridiculous and absurdist.
WebJShrink is a web service for visualizing code bloat within a repository and debloating Java bytecode. It is built atop the hybrid static/dynamic analyzer JShrink, the safest Java debloating solution available. The entire analysis and debloating process is streamlined via WebJShrink with all computation offloaded to cloud.
Watch full length presentation: https://www.youtube.com/watch?v=yzVzcd-MJ1w&feature=youtu.be
https://github.com/0xaa4eb/ulyp
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Hi guys. I want to share my project with you. It's a troubleshooting tool which uses java bytecode instrumentation and has a simple UI written on javafx. You set the following agent properties: packages you want to instrument and a starting point method. When the starting point is executed, tracing is started. As soon as the starting point method call finishes, tracing is deactivated. When tracing is active, it records all method calls of classes in packages you specified.
Orginally, I wrote it 2 years ago as a simple proof-of-concept and started using on my work. The primary usage is troubleshooting and investigating, especially huge enterprise frameworks where debugging usually ends when you realize you have 30+ tabs with code opened. It also may be useful as a research tool when you want to dive into the framework and see what it does.
Please share you thoughts, and critic is especially welcome.
I tried to run java decompiler (JD-Project) to decompile a class file generated from a Kotlin source.
The file generated was not java compatible (I know it's decompiled to java and not Kotlin). But, AFAIK :
- Kotlin compiles to java compatible bytecode and
- JVM doesn't know anything about the programming language making it easier for other languages to target JVM.
If above points hold then the .class file should have decompiled to syntactically correct .java file but, it didn't. I'm not sure why.
I'm unable to find any official source which can clarify this but according to a a bit old stackoverflow link(didn't save it earlier and unable to find it now), Kotlin uses some bytecode tricks which might not result in Java compatible code. Could anyone please provide some clarification on this?
Looking for feedback and collaborators for RemoraJ project. The goal is to have Java IPC & transaction tracing in QA, Test, UAT and production with very low overhead which can be turned on/off on-demand, capture traces and plug into platform of choice. Traces can be used to analyze performance, find bottlenecks, capture stacks traces, heap dumps when standard java profilers can not be used or incur very high overhead. Thoughts?
I was trying to figure this out for a while. When compiling from Java source code directly to machine code instead of bytecode, and having it run natively on the machine, does the JRE need to be installed?
I'm thinking it doesn't because I'm pretty sure it mentions that all the memory and thread management modules are included in the executable. Would it be possible to compile Java to machine code and run it on another machine without the JRE installed?
Does the command jar which creates jar files belong to JRE? When I install JRE, will I have jar? Or do I have to install JDK to have jar? (My experience seems to be that command jar belongs to JDK, but not to JRE. So when I install JRE but not JDK, I don't have command jar.)
There are several JVM languages, such as Java, Scala, Clojure.
Does command jar apply to JVM's bytecode language or to the higher level languages such as Java, Scala, Clojure?
Can command jar be used with all the JVM based high level languages such as Java, Scala, Clojure, or just with Java?
(My guess is that jar applies to JVM bytecode language, so it can be used for packaging purpose with all the JVM based high level languages such as Java, Scala, Clojure ..., since they are all compiled to bytecode before jar applies to them.)
After you compile non-Java JVM-based languages such as Scala, Clojure, how do you do packaging? Can you still use jar command for packaging? Do the SDK releases for Scala and Clojure include jar command? How do you install jar command for these languages?
Thanks.
In the programming class I'm taking at the moment, we're talking about the different ways different languages handle your source code. During the talk, we discussed the advantages and disadvantages of interpreted and compiled languages, and I started wondering what the advantage of compiling to bytecode before interpreting in Java is. As far as I understand, Python just interprets the source code itself, so it seems to be possible.
Why does Java need to compile it first? It's not like the source code gets completely obscured by it, since I know the class files can be at least somewhat converted back, like the fan made modding tools for Minecraft did back in the day. My teacher couldn't answer, so I'm turning to you all. What is the advantage of compiling to bytecode before running in Java?
Title says it all. Looking for the link to the blog post.
Is it possible to write some java byte code and compile it into a .class?
