1 /* 2 * Copyright (C) 2018 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.android.dialer.oem; 18 19 import android.support.annotation.Nullable; 20 import com.android.dialer.common.LogUtil; 21 import java.lang.reflect.InvocationTargetException; 22 import java.lang.reflect.Method; 23 24 /** 25 * Hacky way to call the hidden SystemProperties class API. Needed to get the real value of 26 * ro.carrier and some other values. 27 */ 28 class SystemPropertiesAccessor { 29 private Method systemPropertiesGetMethod; 30 31 @SuppressWarnings("PrivateApi") get(String name)32 public String get(String name) { 33 Method systemPropertiesGetMethod = getSystemPropertiesGetMethod(); 34 if (systemPropertiesGetMethod == null) { 35 return null; 36 } 37 38 try { 39 return (String) systemPropertiesGetMethod.invoke(null, name); 40 } catch (IllegalArgumentException | IllegalAccessException | InvocationTargetException e) { 41 LogUtil.e("SystemPropertiesAccessor.get", "unable to invoke system method", e); 42 return null; 43 } 44 } 45 46 @SuppressWarnings("PrivateApi") getSystemPropertiesGetMethod()47 private @Nullable Method getSystemPropertiesGetMethod() { 48 if (systemPropertiesGetMethod != null) { 49 return systemPropertiesGetMethod; 50 } 51 52 try { 53 Class<?> systemPropertiesClass = Class.forName("android.os.SystemProperties"); 54 if (systemPropertiesClass == null) { 55 return null; 56 } 57 systemPropertiesGetMethod = systemPropertiesClass.getMethod("get", String.class); 58 return systemPropertiesGetMethod; 59 } catch (ClassNotFoundException | NoSuchMethodException e) { 60 LogUtil.e("SystemPropertiesAccessor.get", "unable to access system class", e); 61 return null; 62 } 63 } 64 } 65