public static final boolean TEST_ENV = BuildConfig.TEST_ENV;

// 《Android进阶之光》p214
public class Main {
    private static String convertStreamToString(InputStream stream) throws IOException {
        BufferedReader reader = new BufferedReader(new InputStreamReader(stream));
        StringBuffer sb = new StringBuffer();
        String line;
        while ((line = reader.readLine()) != null) {
            sb.append(line).append("\n");
        }
        String response = sb.toString();
        return response;
    }

    // https://stackoverflow.com/questions/43157/easy-way-to-write-contents-of-a-java-inputstream-to-an-outputstream
    // http://commons.apache.org/proper/commons-io/apidocs/org/apache/commons/io/IOUtils.html
    // http://commons.apache.org/proper/commons-io/download_io.cgi
    public static void convertStreamToFile(InputStream in, File out) throws IOException {
        FileOutputStream outStream = new FileOutputStream(out);
        IOUtils.copy(in, outStream);
        in.close();
        outStream.close();
    }

    public static void main(String[] args) {
        // 网络图片
        InputStream stream = new URL("https://www.cnblogs.com/images/logo_small.gif").openStream();

        convertStreamToFile(stream, new File("./java/cnblog_logo.png"));

        // 网页
        InputStream stream2 = new URL("https://www.cnblogs.com/").openStream();

        convertStreamToFile(stream2, new File("./java/cnblog.html"));

        // 本地文件
        FileInputStream fileInputStream = new FileInputStream("./java/hi.txt");

        convertStreamToFile(fileInputStream, new File("./java/hi2.txt"));

        // 获取字符串
        FileInputStream fileInputStream2 = new FileInputStream("./java/hi.txt");
        String str = convertStreamToString(fileInputStream2);
        System.out.println(str);
    }
}

ScheduledExecutorService service = Executors.newScheduledThreadPool(1);
service.schedule(new Runnable() {
    @Override
    public void run() {
        System.out.println("Yeah, I'm late.");
        service.shutdown();
    }
}, 10, TimeUnit.SECONDS);

URL url = new URL("http://lyloou.com");
URLConnection uc = url.openConnection();// 获取连接对象
uc.connect();// 连接
long webTimeMillis = uc.getDate();
SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss", Locale.CHINA);
String formatWebTime = simpleDateFormat.format(new Date(webTimeMillis));
System.out.println(formatWebTime);

String strDate = "2017-05-09T14:28:32.974Z";
SimpleDateFormat inputFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SS'Z'");
SimpleDateFormat outputFormat = new SimpleDateFormat("yy/MM/dd HH:mm:ss");
try {
    Date inputDate = inputFormat.parse(strDate);
    String outputDate = outputFormat.format(inputDate);
    System.out.println(outputDate);
} catch (ParseException e) {
    e.printStackTrace();
}

System.out.println(Arrays.toString(list.toArray()));

private static final Map<String, Object> objectsCache = new HashMap<>();

// put in
public void putIn(String key, Object obj) {
  objectsCache.put(key, obj);
}

// get out
public Object getOut(String key, Object default) {
  if(objectsCache.containsKey(key)) {
    Object obj = objectsCache.get(key);
    if(obj == null) {
      objectsCache.put(key, default);
    }
    return obj;
  } else {
    objectsCache.put(key, default);
    return default;
  }
}

MyClass mobj = MyClass.class.cast(obj);
// or
Object newObj = Class.forName(classname).cast(obj);

//: 通过程序证明来时间戳只有一个；
public class TimeTest {

    public static void main(String[] args) {
        Calendar now = new GregorianCalendar();
        System.out.println(TimeZone.getDefault());
        System.out.println(now.getTime());
        System.out.println(now.getTime().getTime());
        System.out.println();

        TimeZone.setDefault(TimeZone.getTimeZone("GMT+8"));
        System.out.println(TimeZone.getDefault());
        System.out.println(now.getTime());
        System.out.println(now.getTime().getTime());
        System.out.println();

        TimeZone.setDefault(TimeZone.getTimeZone("GMT+0"));
        System.out.println(TimeZone.getDefault());
        System.out.println(now.getTime());
        System.out.println(now.getTime().getTime());
        System.out.println();

        TimeZone.setDefault(TimeZone.getTimeZone("GMT+12"));
        System.out.println(TimeZone.getDefault());
        System.out.println(now.getTime());
        System.out.println(now.getTime().getTime());
    }
}
/*
sun.util.calendar.ZoneInfo[id="Asia/Shanghai",offset=28800000,dstSavings=0,useDaylight=false,transitions=19,lastRule=null]
Thu Aug 10 09:39:22 CST 2017
1502329162745

sun.util.calendar.ZoneInfo[id="GMT+08:00",offset=28800000,dstSavings=0,useDaylight=false,transitions=0,lastRule=null]
Thu Aug 10 09:39:22 GMT+08:00 2017
1502329162745

sun.util.calendar.ZoneInfo[id="GMT+00:00",offset=0,dstSavings=0,useDaylight=false,transitions=0,lastRule=null]
Thu Aug 10 01:39:22 GMT+00:00 2017
1502329162745

sun.util.calendar.ZoneInfo[id="GMT+12:00",offset=43200000,dstSavings=0,useDaylight=false,transitions=0,lastRule=null]
Thu Aug 10 13:39:22 GMT+12:00 2017
1502329162745
*///~