Variables and Pointers in an Isolated Environment like Virtual Machines [closed] - bytecode

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I'm wondering how a programming language like Java can handle Variables and/or Pointers in an isolated environment like Java Virtual Machine and its own Byte-Code.
Examples in Assembly or binary equivalents are highly appreciated.

I suggest you read a little of how Java actually works.
Java doesn't have pointers, it has references which you cannot examine in pure Java. An important distinction about references in Java is that they
can change at any time without notice
don't have to be a direct address in memory. It can be encoded. e.g. to allow 32-bit references to access up to 32 GB of memory.
It has variables like any other language but you can't get a reference to them.
The byte code is a literal translation of the Java code and read it is unlikely to be more useful than reading the Java code unles syou have a deep understanding of Java. Note: the JVM compiles this to native code, so it is not the code actually run much of the time.

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Cheat Engine vs Ollydbg [closed]

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What is the difference between both programs besides that one is used for cheating at games and the other is a debugger? I know that Cheat Engine is a memory editor. But what does Ollydbg do exactly; does it only edit .exe files?
CE it's focused on memory editing and analisys, Olly can do the same as CE but its focus is code analysis and patching, there is tasks that you can use both, a case is that CE can easily find a portion of code that changes memory (Olly can do it too but CE makes it very easy) and than you can modify the code with olly.
OllyDbg is a 32-bit assembler level analyzing debugger with a lot of tools Emphasizing on binary code analysis makes it particularly useful in cases
where source is unavailable.
but cheat engine is simple and user friendly app designed
for easier searching in memory and making simple scripts for trainers.

vb6 ADODB.stream doesn't exist. .what shall i do? [closed]

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ADODB.Stream doesn't exist in my Visual Basic 6. . I searched everywhere in the objects browser. Is there any method or installation so that i could provide it???
thanks guys
Go to Projects>References>Microsoft ActiveX Data Objects 2.8 Library.
Then go to form and type the code.
It should come up as Intellisense.
You probably are looking for "ADODB" when the library isn't called that at all. Normal language usage would just call this "ADO" but the Web is full of cargo-culters. Why there is an "ADODB" tag here at all escapes me.
Look for a version of "Microsoft ActiveX Data Objects." Usually 2.5 is a reasonable choice unless you have good reasons to target a new version of the interface - they all point to the same DLL.
This is a system library used from all kinds of languages. It has nothing directly to do with VB6, and is part of Windows now (and has been for well over a decade).

Is there an entry point in Ruby code execution to be used by a Ruby profiler? [closed]

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I have a Java profiler which is a JavaAgent which does BCI on my classes and reports the statistics.
I was trying to create a basic profiler for Ruby as well (just for learning). I was wondering is there a similar mechanism for Ruby as well where I can provide a profiler class to be executed when I start my standalone Ruby program and it starts reporting statistics for the program.
I can search for getting statistics from Ruby however currently my concern is how to invoke the profiler class before execution begins for my code. Note that in case of JavaAgent, no source files needed to be modified as the byte code was directly instrumented instead of source files.
I expect a similar solution for Ruby as well, so that I dont need to modify my source files. In case my approach itself is wrong, is there any guideline or approach that I should follow for creating my basic profiler would be really helpful.
How can I cause my profiler class to be invoked before Ruby begins executing the code being profiled?
http://www.newrelic.com/ruby is really good, and there is a developer mode, you can take a look: https://docs.newrelic.com/docs/ruby/developer-mode

What programming languages are normally compiled into non-machine specific code? [closed]

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Any specific reasons would be nice too.
As some people have pointed out; Java is translated into Bytecode, which runs in JVM. Are there any which don't depend on a virtual machine? Historical or contemporary, obsolete or not.
As already pointed out, portable ByteCode is platform independent,
you can find a List of ByteCode Languages on eg. wikipedia.
But they depend on an Interpreter or a Virtual Machine, ie. JVM.
And there is also LLVM, which provides a middle layer in an intermediate form (IF).

possible issues with class dependencies in Ruby [closed]

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After learning power of Rails framework, I have started learning ruby. In Ruby, I learnt that I can add methods to a class at runtime. In Java, we have to define all methods before compilation. I suppose, this advantage in Ruby gives rise to issues with class dependancies. As I am new to Ruby, could anyone please explain in what way do I lose control by adding methods dynamically.
Being able to add methods at runtime doesn't impact the dependencies in any way, or at least not any more than writing any other code would.
The only difference is that you can now have methods "written" as-needed, but you will still have the same dependency issues if you wrote the code yourself. Since ruby is a dynamic language, it's sense of dependencies is rather different from a more "traditional" statically compiled language like C++ or Java, but even in Java you can load arbitrary code at runtime (it's much more difficult, but still possible).

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