Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
import android.util.Log;
import java.io.File;
import java.lang.reflect.Array;
import java.lang.reflect.Field;
import dalvik.system.BaseDexClassLoader;
import dalvik.system.DexClassLoader;

public class Main {
    public static boolean overrideClassLoader(ClassLoader cl, File dex, File opt) {
        try {
            ClassLoader bootstrap = cl.getParent();
            Field fPathList = BaseDexClassLoader.class.getDeclaredField("pathList");
            fPathList.setAccessible(true);
            Object pathList = fPathList.get(cl);
            Class cDexPathList = bootstrap.loadClass("dalvik.system.DexPathList");
            Field fDexElements = cDexPathList.getDeclaredField("dexElements");
            fDexElements.setAccessible(true);
            Object dexElements = fDexElements.get(pathList);
            DexClassLoader cl2 = new DexClassLoader(dex.getAbsolutePath(), opt.getAbsolutePath(), null, bootstrap);
            Object pathList2 = fPathList.get(cl2);
            Object dexElements2 = fDexElements.get(pathList2);
            Object element2 = Array.get(dexElements2, 0);
            int n = Array.getLength(dexElements) + 1;
            Object newDexElements = Array.newInstance(fDexElements.getType().getComponentType(), n);
            Array.set(newDexElements, 0, element2);
            for (int i = 0; i < n - 1; i++) {
                Object element = Array.get(dexElements, i);
                Array.set(newDexElements, i + 1, element);
            }
            fDexElements.set(pathList, newDexElements);
            return true;
        } catch (Exception e) {
            Log.e("lcast", "fail to override classloader " + cl + " with " + dex, e);
            return false;
        }
    }
}