Android APK Dynamic Loading technology Research (1) Basic knowledge training

Java ClassLoader vs. Android Dexclassloader:

Java ClassLoader:    function:  mainly used to load the class into the JVM for the program to use, that is to say: Java program can dynamically load the class definition, and this dynamic loading mechanism is implemented through the    ClassLoader Core loader:          A:: Bootstrap ClassLoader (startup ClassLoader)--load the Java Core API, including user-defined ClassLoader and two additional loader         B: Extclassloader-"Load extension API in Java, that is, class C:appclassloader in/lib/ext  --" Loader Ape's custom class, This is the class loading process under our engineering classpath  :      1: When running a Java program, the JVM starts      2: Runs bootstrap ClassLoader, loads the Java Core API (Extclassloader And Appclassloader are also loaded at this time)      3: Call extclassloader Load Extension API      4: Finally Appclassloader load the custom class under Classpath directory

Android  dexclassloader      role:           Android Development and common Java development is different from the class file is repackaged into the Dex type of file, This re-packaging optimizes the various function tables and variable tables inside the class file. The Dex file is a class file optimized by the Android packaging tool, so loading this special class file requires a special ClassLoader, so the Dexclassloader loading process is available in Android     :       1: Get the installation directory for the specified apk via Packagemanager, Dex's unzip directory, directory      2: Create a Dexclassloader instance      3: Load the specified class to return a      class 4: Then use reflection to call this class

Finally add a bit of Android knowledge, for the next article to prepare, that is, Android resource management, first look at this article to do an understanding of the first: http://blog.csdn.net/luoshengyang/article/details/8738877/

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Android APK Dynamic Loading technology Research (1) Basic knowledge training