Android的Dex反編譯器設計與實作：控制結構部分

Abstract

隨著Android應用日漸普及，在不久的將來，使用者對於Android應用程式勢必會有不同的最佳化需求，甚至是轉換成不同的檔案格式，例如將Dex檔案轉換回Java檔案。然而，以現階段來說，針對Java及Class檔案開發的二元轉換及最佳化框架資源，是遠比Dex檔案所擁有的豐富。因此，我們希望在Java家族的二元轉換上建立一條路徑，使得Dex檔案也能享受到屬於Class檔案的資源。 我們的研究目標是開發Dex檔案回到Java檔案的反編譯器。本篇論文將專注於控制結構的建立，引用了Class-to-Java反編譯器的Goto Elimination方法，再針對Dex檔案的特性修改，以達到移除goto指令，建立對應控制結構的目標。最後依照建立的控制結構，寫出Java原始檔。

Because Android is more and more popular, users will have different optimization request about Android applications in the near future. They also have to transform the file into different format, such as transforming Android dex file to Java source file. However, the resources of binary transformations and optimization frameworks for Java source and Java class file are much more fruitful than those for Android dex file. In this thesis, we want to create a binary transformation path from Android dex file to Java source and Java class file. Our goal is to develop a Dex-to-Java decompiler. This thesis will focus on control structure creation. We adopt the goto-elimination algorithm of a Class-to-Java decompiler. And then, according to Android dex property, we modify the algorithm in order to remove goto instructions and construct corresponding control structures. Finally, we can write down the Java source file according to these control structures.