title: How to shrink external lib to my own Android Library build
body: <p>My library refers some big size jar, e.g. guava, math3, but i only use one or two method of them.
  Could i shrink the third-part codes to my library?
  Because with current aar output, my library size seems small, but for application used my lib, it will download all the third-part jars and build the whole code into their apk, which results a big size.</p>
  
  <p>The "aar" seems only records which library it will use, but not compile the used code into it. Is there a library output type supports shrinking the code?</p>
  
  <p>I see suggestion to use proguard, or minifyEnalbed. They don't work for what i wanted.
  Is any one familiar with compiler or aar/jar? is it possible to package all the code in one file, not download the jars when apk compile?</p>