content: package com.rsen.github.androidutilcode;
  
  import android.app.ActivityManager;
  import android.app.AppOpsManager;
  import android.app.usage.UsageStats;
  import android.app.usage.UsageStatsManager;
  import android.content.Context;
  import android.content.Intent;
  import android.content.pm.ApplicationInfo;
  import android.content.pm.PackageManager;
  import android.content.pm.ResolveInfo;
  import android.provider.Settings;
  
  import java.util.Arrays;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Set;
  
  /**
   * <pre>
   *     author: Blankj
   *     blog  : http://blankj.com
   *     time  : 2016/10/18
   *     desc  : 进程相关工具类
   * </pre>
   */
  public class ProcessUtils {
  
      private ProcessUtils() {
          throw new UnsupportedOperationException("u can't instantiate me...");
      }
  
      /**
       * 获取前台应用包名
       * <p>当不是查看当前App，且SDK >= 22时，
       * 需添加权限 {@code <uses-permission android:name="android.permission.PACKAGE_USAGE_STATS"/>}</p>
       *
       * @param context 上下文
       * @return 前台应用包名
       */
      public static String getForegroundProcessName(Context context) {
          ActivityManager manager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
          List<ActivityManager.RunningAppProcessInfo> infos = manager.getRunningAppProcesses();
          if (infos != null && infos.size() != 0) {
              for (ActivityManager.RunningAppProcessInfo info : infos) {
                  if (info.importance == ActivityManager.RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {
                      return info.processName;
                  }
              }
          }
          if (android.os.Build.VERSION.SDK_INT > android.os.Build.VERSION_CODES.LOLLIPOP) {
              PackageManager packageManager = context.getPackageManager();
              Intent intent = new Intent(Settings.ACTION_USAGE_ACCESS_SETTINGS);
              List<ResolveInfo> list = packageManager.queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY);
              System.out.println(list);
              if (list.size() > 0) {// 有"有权查看使用权限的应用"选项
                  try {
                      ApplicationInfo info = packageManager.getApplicationInfo(context.getPackageName(), 0);
                      AppOpsManager aom = (AppOpsManager) context.getSystemService(Context.APP_OPS_SERVICE);
                      if (aom.checkOpNoThrow(AppOpsManager.OPSTR_GET_USAGE_STATS, info.uid, info.packageName) != AppOpsManager.MODE_ALLOWED) {
                          context.startActivity(intent);
                      }
                      if (aom.checkOpNoThrow(AppOpsManager.OPSTR_GET_USAGE_STATS, info.uid, info.packageName) != AppOpsManager.MODE_ALLOWED) {
                          LogUtils.d("getForegroundApp", "没有打开\"有权查看使用权限的应用\"选项");
                          return null;
                      }
                      UsageStatsManager usageStatsManager = (UsageStatsManager) context.getSystemService(Context.USAGE_STATS_SERVICE);
                      long endTime = System.currentTimeMillis();
                      long beginTime = endTime - 86400000 * 7;
                      List<UsageStats> usageStatses = usageStatsManager.queryUsageStats(UsageStatsManager.INTERVAL_BEST, beginTime, endTime);
                      if (usageStatses == null || usageStatses.isEmpty()) return null;
                      UsageStats recentStats = null;
                      for (UsageStats usageStats : usageStatses) {
                          if (recentStats == null || usageStats.getLastTimeUsed() > recentStats.getLastTimeUsed()) {
                              recentStats = usageStats;
                          }
                      }
                      return recentStats == null ? null : recentStats.getPackageName();
                  } catch (PackageManager.NameNotFoundException e) {
                      e.printStackTrace();
                  }
              } else {
                  LogUtils.d("getForegroundApp", "无\"有权查看使用权限的应用\"选项");
              }
          }
          return null;
      }
  
      /**
       * 清除后台进程
       * <p>需添加权限 {@code <uses-permission android:name="android.permission.KILL_BACKGROUND_PROCESSES"/>}</p>
       *
       * @param context 上下文
       * @return 清除后台进程数
       */
      public static int cleanAllBackgroundProcesses(Context context) {
          int count = 0;
          ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
          List<ActivityManager.RunningAppProcessInfo> infos = am.getRunningAppProcesses();
          if (infos == null || infos.size() == 0) return 0;
          Set<ActivityManager.RunningAppProcessInfo> set = new HashSet<>();
          for (ActivityManager.RunningAppProcessInfo info : infos) {
              infos.remove(info);
              set.add(info);
              ++count;
          }
          infos = am.getRunningAppProcesses();
          if (infos == null || infos.size() == 0) return count;
          for (ActivityManager.RunningAppProcessInfo info : infos) {
              set.remove(info);
              --count;
          }
          System.out.println(set);
          return count;
      }
  
      /**
       * 清除后台进程
       * <p>需添加权限 {@code <uses-permission android:name="android.permission.KILL_BACKGROUND_PROCESSES"/>}</p>
       *
       * @param context     上下文
       * @param packageName 包名
       * @return {@code true}: 清除成功<br>{@code false}: 清除失败
       */
      public static boolean cleanBackgroundProcesses(Context context, String packageName) {
          if (StringUtils.isSpace(packageName)) return false;
          ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
          List<ActivityManager.RunningAppProcessInfo> infos = am.getRunningAppProcesses();
          if (infos == null || infos.size() == 0) return true;
          for (ActivityManager.RunningAppProcessInfo info : infos) {
              if (Arrays.asList(info.pkgList).contains(packageName)) {
                  am.killBackgroundProcesses(packageName);
              }
          }
          infos = am.getRunningAppProcesses();
          if (infos == null || infos.size() == 0) return true;
          for (ActivityManager.RunningAppProcessInfo info : infos) {
              if (Arrays.asList(info.pkgList).contains(packageName)) {
                  return false;
              }
          }
          return true;
      }
  }
  