title: Decompile an APK, modify it and then recompile it
body: <p>I need to modify an existing APK, modify the sources and then recompile it.</p>
  
  <ul>
  <li>I can decompile it using dex2jar or apktool, it's working great </li>
  <li>From the jar file I can obtain the java sources (using jd-gui)</li>
  <li>Then I can modify the java files</li>
  </ul>
  
  <p>But now I would like to know how to recompile the java files and put them back into a jar file! (the jar part should be easy, the main problem seems to be how to recompile the java files for android)</p>
  
  <p>I know that an other solution is to use apktool and then modify the smali files, but it seems to be really complicated when we want to add a lot of code!</p>
  
  <p>My application is a basic a HelloWorld whitout obfuscation.</p>