RocooUtils.java

/*
 * Copyright (C) 2016 Baidu, Inc. All Rights Reserved.
 */
package com.dodola.rocoofix;

import java.io.File;
import java.io.IOException;
import java.lang.reflect.Array;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

/**
 * Created by sunpengfei on 16/7/30.
 */
public class RocooUtils {
    /**
     * Locates a given field anywhere in the class inheritance hierarchy.
     *
     * @param instance an object to search the field into.
     * @param name field name
     * @return a field object
     * @throws NoSuchFieldException if the field cannot be located
     */
    static Field findField(Object instance, String name) throws NoSuchFieldException {
        for (Class<?> clazz = instance.getClass(); clazz != null; clazz = clazz.getSuperclass()) {
            try {
                Field field = clazz.getDeclaredField(name);

                if (!field.isAccessible()) {
                    field.setAccessible(true);
                }

                return field;
            } catch (NoSuchFieldException e) {
                // ignore and search next
            }
        }

        throw new NoSuchFieldException("Field " + name + " not found in " + instance.getClass());
    }

    /**
     * Locates a given method anywhere in the class inheritance hierarchy.
     *
     * @param instance an object to search the method into.
     * @param name method name
     * @param parameterTypes method parameter types
     * @return a method object
     * @throws NoSuchMethodException if the method cannot be located
     */
    static Method findMethod(Object instance, String name, Class<?>...parameterTypes) throws NoSuchMethodException {
        for (Class<?> clazz = instance.getClass(); clazz != null; clazz = clazz.getSuperclass()) {
            try {
                Method method = clazz.getDeclaredMethod(name, parameterTypes);

                if (!method.isAccessible()) {
                    method.setAccessible(true);
                }

                return method;
            } catch (NoSuchMethodException e) {
                // ignore and search next
            }
        }

        throw new NoSuchMethodException("Method " + name + " with parameters " + Arrays.asList(parameterTypes)
                + " not found in " + instance.getClass());
    }

    /**
     * Replace the value of a field containing a non null array, by a new array containing the elements of the original
     * array plus the elements of extraElements.
     *
     * @param instance the instance whose field is to be modified.
     * @param fieldName the field to modify.
     * @param extraElements elements to append at the end of the array.
     */
    static void expandFieldArray(Object instance, String fieldName, Object[] extraElements)
            throws NoSuchFieldException, IllegalArgumentException, IllegalAccessException {
        Field jlrField = findField(instance, fieldName);
        Object[] original = (Object[]) jlrField.get(instance);
        Object[] combined =
                (Object[]) Array.newInstance(original.getClass().getComponentType(), original.length
                        + extraElements.length);
        System.arraycopy(extraElements, 0, combined, 0, extraElements.length);
        System.arraycopy(original, 0, combined, extraElements.length, original.length);
        jlrField.set(instance, combined);
    }

    public static Object[] makePathElements(Object dexPathList, ArrayList<File> files, File optimizedDirectory,
                                            ArrayList<IOException> suppressedExceptions) throws IllegalAccessException, InvocationTargetException,
            NoSuchMethodException {
        return (Object[]) findMethod(dexPathList, "makePathElements", List.class, File.class, List.class).invoke(
                dexPathList, files, optimizedDirectory, suppressedExceptions);
    }
}