Bytecode Viewer is an Advanced Lightweight Java Bytecode Viewer, GUI Java Decompiler, GUI Bytecode Editor, GUI Smali, GUI Baksmali, GUI APK Editor, GUI Dex Editor, GUI APK Decompiler, GUI DEX Decompiler, GUI Procyon Java Decompiler, GUI Krakatau, GUI CFR Java Decompiler, GUI FernFlower Java Decompiler, GUI DEX2Jar, GUI Jar2DEX, GUI Jar-Jar, Hex Viewer, Code Searcher, Debugger and more.

It's written completely in Java, and it's open sourced. It's currently being maintained and developed by Konloch.

There is also a plugin system that will allow you to interact with the loaded classfiles, for example you can write a String deobfuscator, a malicious code searcher, or something else you can think of.
You can either use one of the pre-written plugins, or write your own. It supports groovy scripting. Once a plugin is activated, it will execute the plugin with a ClassNode ArrayList of every single class loaded in BCV, this allows the user to handle it completely using ASM.

Code from various projects has been used, including but not limited to:

•     J-RET by WaterWolf
•     JHexPane by Sam Koivu
•     RSynaxPane by Robert Futrell
•     Commons IO by Apache
•     ASM by OW2
•     FernFlower by Stiver
•     Procyon by Mstrobel
•     CFR by Lee Benfield
•     CFIDE by Bibl
•     Smali by JesusFreke
•     Dex2Jar by pxb1..?
•     Krakatau by Storyyeller
•     JD GUI/JD Core by The Java-Decompiler Team
•     Enjarify by Storyyeller

Features:

• Easy to use yet extremely effective.
• Written to run on Java 7, supports Java 8.
• Compile Decompiled Java classes with Ranino Compiler.
• Quickly decompile classes using JD-Core.
• Easily edit APKs via Smali/Baksmali integration.
• Java Decompiling with five different decompilers (DJ-GUI/Core, Procyon, CFR, Fernflower and Krakatau).
• Bytecode Decompiling with CFIDE.
• Android APK integrated with Dex2Jar.
• Securely launch Java applications and insert hooks via EZ-Injection.
• Scan for malicious code with the Malicious Code Scanner plugin.
• Export as DEX, Jar, Class, Zip or Java Source File.
• Open Android APKs, Android DEX, Java Class Files and Java Jars.
• Extensively configurable, over 100+ settings!
• Works seamlessly with all Operating Systems.
• Integrate BCV into Windows by installing it, it'll associate all .class, .dex and .apk to open with BCV.
• View Jar & APK Resources with ease by APKTool.jar integration.
• 100% free and open sourced under GPL v3 CopyLeft.

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