XposedHelpers.java 文件源码

/**
 * Returns the index of the parameter declared with the given type, ensuring that there is exactly one such parameter.
 *
 * @throws NoSuchFieldError if there is no or more than one parameter with that type.
 */
public static int getParameterIndexByType(final Member method, final Class<?> type) {
    final Class<?>[] classes = (method instanceof Method) ?
            ((Method) method).getParameterTypes() : ((Constructor<?>) method).getParameterTypes();
    int idx = -1;
    for (int i = 0; i < classes.length; ++i) {
        if (classes[i] == type) {
            if (idx == -1) {
                idx = i;
            } else {
                throw new NoSuchFieldError("More than one parameter of type " + type + " found in " + method);
            }
        }
    }
    if (idx != -1) {
        return idx;
    } else {
        throw new NoSuchFieldError("No parameter of type " + type + " found in " + method);
    }
}