热更新

生成更新jar包

image.png

调用jar包

public class ReflectUtil {
    public static void installPatch(Application application, File patchFile){
        if (!patchFile.exists()){
            return;
        }
        
        ClassLoader classLoader = application.getClassLoader();

        try {
            Field pathListField = findField(classLoader, "pathList");
            Object pathList = pathListField.get(classLoader);

            List<File> files = new ArrayList<>();
            files.add(patchFile);

            File dexOutputDir = application.getCodeCacheDir();
            ArrayList<IOException> suggestExceptions = new ArrayList<>();

            Method makePathElements = findMethod(pathList, "makePathElements", List.class, File.class, List.class);

            Object[] patchElements = (Object[]) makePathElements.invoke(pathList, files, dexOutputDir, suggestExceptions);

            Field dexElementField = findField(pathList, "dexElements");
            Object[] dexElements = (Object[])dexElementField.get(pathList);

            Object[] newElements = (Object[]) Array.newInstance(patchElements.getClass().getComponentType(), patchElements.length + dexElements.length);

            System.arraycopy(patchElements, 0, newElements, 0, patchElements.length);
            System.arraycopy(dexElements, 0, newElements, patchElements.length, dexElements.length);

            dexElementField.set(pathList, newElements);
            Log.e("chy", "aa");
        }
        catch (Exception e){
            Toast.makeText(application, e.toString(), Toast.LENGTH_LONG).show();
        }
    }

    public static Field findField(Object instance, String name){

        Class<?> cls = instance.getClass();
        while (cls != Object.class){
            try {
                Field field = cls.getDeclaredField(name);
                field.setAccessible(true);
                return field;
            }
            catch (Exception e){

            }
            cls = cls.getSuperclass();
        }
        throw new RuntimeException(name + " filed not found");
    }

    public static Method findMethod(Object instance, String name, Class<?>... parameterType){

        Class<?> cls = instance.getClass();
        while (cls != Object.class){
            try {
                Method method = cls.getDeclaredMethod(name, parameterType);
                method.setAccessible(true);
                return method;
            }
            catch (Exception e){

            }
            cls = cls.getSuperclass();
        }
        throw new RuntimeException(name + " method not found");
    }
}

备注：一定要注意文件权限