Topic: Создаем на Java Наблюдателя за Ценой Биткоина (Read 205 times)

private void scanConsole() {
  String command = null;
  Scanner scanner = new Scanner(System.in);

  while (!QUIT_COMMAND.equals(command)) {
    String line = scanner.nextLine();
    line = line.toUpperCase();

    if (line.startsWith(QUIT_COMMAND)) {
      command = QUIT_COMMAND;
      System.out.println("Goodbye!");
    } else if (line.startsWith(LIST_COMMAND)) {
      command = LIST_COMMAND;
      listPricesToWatch();

    } else {
      String[] tmp = line.split(";");

      if (tmp.length != 2) {
        System.out.println("Bad entry: COMMAND;Price");
      } else {
        command = tmp[0];

        // we use a switch for future commands
        switch (command) {
          case WATCH_COMMAND:
            Float price = null;

            try {
              price = Float.parseFloat(tmp[1]);
            } catch (Exception e) {
              price = null;
            }

            if (price == null) {
              System.out.println("Bad price");
            } else {
              Price priceObj = new Price(currentPrice, price);
              pricesToWatch.add(priceObj);
              System.out.println("Watch for BTC " + priceObj.type + " = " + price);
            }
            break;
          }

      }

    }
  }

  scanner.close();
  cancelTimer();
  System.exit(0);
}

package com.ssaurel.BitcoinPriceAlert;

import java.awt.AWTException;
import java.awt.Image;
import java.awt.SystemTray;
import java.awt.Toolkit;
import java.awt.TrayIcon;
import java.awt.TrayIcon.MessageType;
import java.io.IOException;
import java.time.LocalDateTime;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Scanner;
import java.util.Timer;
import java.util.TimerTask;

import org.json.JSONObject;

import okhttp3.Call;
import okhttp3.Callback;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;

public class App {

 public static final String WATCH_COMMAND = "WATCH";
 public static final String QUIT_COMMAND = "QUIT";
 public static final String LIST_COMMAND = "LIST";
 public static final long PERIOD = 60 * 1000; // 30 sec
 public static final String BITCOIN_PRICE_ENDPOINT = "https://api.coindesk.com/v1/bpi/currentprice.json";
 private OkHttpClient client = new OkHttpClient();
 private Timer timer;
 private List pricesToWatch;
 private float currentPrice;

 public static void main(String[] args) {
  App app = new App();
  app.launchTimer();
  app.scanConsole();
 }

 public App() {
  pricesToWatch = new ArrayList<>();
 }

 private void scanConsole() {
  String command = null;
  Scanner scanner = new Scanner(System.in);

  while (!QUIT_COMMAND.equals(command)) {
   String line = scanner.nextLine();
   line = line.toUpperCase();
 
   if (line.startsWith(QUIT_COMMAND)) {
    command = QUIT_COMMAND;
    System.out.println("Goodbye!");
   } else if (line.startsWith(LIST_COMMAND)) {
    command = LIST_COMMAND;
    listPricesToWatch();
    
   } else {
    String[] tmp = line.split(";");

    if (tmp.length != 2) {
     System.out.println("Bad entry: COMMAND;Price");
    } else {
     command = tmp[0];

     // use a switch for future commands
     switch (command) {
     case WATCH_COMMAND:
      Float price = null;

      try {
       price = Float.parseFloat(tmp[1]);
      } catch (Exception e) {
       price = null;
      }

      if (price == null) {
       System.out.println("Bad price");
      } else {
       Price priceObj = new Price(currentPrice, price);
       pricesToWatch.add(priceObj);
       System.out.println("Watch for BTC " + priceObj.type + " = " + price);
      }
      break;
     }

    }

   }
  }

  scanner.close();
  cancelTimer();
  System.exit(0);
 }

 private void listPricesToWatch() {
  if (pricesToWatch.isEmpty()) {
   System.out.println("No prices to watch");
  } else {
   System.out.println("Prices to watch:");
   
   for (Price price : pricesToWatch) {
    System.out.println("\t" + price.type + "\t" + price.target);
   }
  }
  
  System.out.println();
 }
 
 private void launchTimer() {
  timer = new Timer();
  timer.schedule(new TimerTask() {

   @Override
   public void run() {
    loadBitcoinPrice(new Callback() {

     @Override
     public void onResponse(Call call, Response response) throws IOException {
      String str = response.body().string();
      parseBitcoinPrice(str);
     }

     @Override
     public void onFailure(Call call, IOException ioe) {

     }
    });
   }
  }, 0, PERIOD);
 }

 private void cancelTimer() {
  if (timer != null) {
   timer.cancel();             
  }
 }

 private void loadBitcoinPrice(Callback callback) {
  Request request = new Request.Builder().url(BITCOIN_PRICE_ENDPOINT).build();
  client.newCall(request).enqueue(callback);
 }

 private void parseBitcoinPrice(String str) {
  JSONObject jsonObject = new JSONObject(str);
  currentPrice = jsonObject.getJSONObject("bpi").getJSONObject("USD").getFloat("rate_float");
  System.out.println(LocalDateTime.now() + " | Current price = " + currentPrice + "\n");

  // we check if one price is reached
  for (Iterator it = pricesToWatch.iterator(); it.hasNext();) {
   Price priceToWatch = it.next();

   if (priceToWatch.type.reached(currentPrice, priceToWatch.target)) {
    String message = priceToWatch.type.msg(currentPrice, priceToWatch.target);
    System.out.println(message); 
    displayNotification("Bitcoin Watcher", message);
    // remove from list to watch
    it.remove();
   }

  }
 }
 
 public void displayNotification(String title, String message) {
  if (SystemTray.isSupported()) {
   //Obtain only one instance of the SystemTray object
   SystemTray tray = SystemTray.getSystemTray();
   Image image = Toolkit.getDefaultToolkit().createImage("icon.png");

   TrayIcon trayIcon = new TrayIcon(image, "Bitcoin Watcher Notif");
   //Let the system resize the image if needed
   trayIcon.setImageAutoSize(true);
   //Set tooltip text for the tray icon
   trayIcon.setToolTip("Bitcoin Watcher");
   
   try {
     tray.add(trayIcon);
   } catch (AWTException e) { }

   trayIcon.displayMessage(title, message, MessageType.INFO);
  } else {
   System.err.println("System tray not supported!");
  }
 }

}

    xmlns="http://maven.apache.org/POM/4.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    4.0.0
    com.ssaurel
    BitcoinPriceAlert
    0.0.1-SNAPSHOT
    jar
    BitcoinPriceAlert
    http://maven.apache.org
    
        UTF-8
    
    
        
            com.squareup.okhttp3
            okhttp
            4.2.2
        
        
            org.json
            json
            20190722
        
        
            junit
            junit
            3.8.1
            test
        
    

private void loadBitcoinPrice(Callback callback) {
  Request request = new Request.Builder().url(BITCOIN_PRICE_ENDPOINT).build();
  client.newCall(request).enqueue(callback);
}

private void launchTimer() {
 timer = new Timer();
 timer.schedule(new TimerTask() {
   @Override
   public void run() {
     loadBitcoinPrice(new Callback() {
       @Override
       public void onResponse(Call call, Response response) throws IOException {
         String str = response.body().string();
         parseBitcoinPrice(str);
       }

       @Override
       public void onFailure(Call call, IOException ioe) { }
    });
   }
  }, 0, PERIOD);
}

private void cancelTimer() {
 if (timer != null) {
  timer.cancel();
 }
}

private void loadBitcoinPrice(Callback callback) {
 Request request = new Request.Builder().url(BITCOIN_PRICE_ENDPOINT).build();
 client.newCall(request).enqueue(callback);
}

private void parseBitcoinPrice(String str) {
  JSONObject jsonObject = new JSONObject(str);
  currentPrice = jsonObject.getJSONObject("bpi").getJSONObject("USD").getFloat("rate_float");
  System.out.println(LocalDateTime.now() + " | Current price = " + currentPrice + "\n");
  
  // ...
}

public class Price {

  enum Type {
    UP() {
      @Override
      public boolean reached(float current, float target) {
        return target < current;
      }

      @Override
      public String msg(float current, float target) {
        return "BTC has rised beyond " + target + " with price : " + current;
      }
    },
    DOWN {
      @Override
      public boolean reached(float current, float target) {
        return current < target;
      }

      @Override
      public String msg(float current, float target) {
        return "BTC has fallen below " + target + " with price : " + current;
      }
    };

    public abstract boolean reached(float current, float target);
    public abstract String msg(float current, float target);
  }

  public float target;
  public Type type;

  public Price(float current, float target) {
    this.target = target;
    type = Float.compare(current, target) < 0 ? Type.UP : Type.DOWN;
  }

}

private void parseBitcoinPrice(String str) {
  JSONObject jsonObject = new JSONObject(str);
  currentPrice = jsonObject.getJSONObject("bpi").getJSONObject("USD").getFloat("rate_float");
  System.out.println(LocalDateTime.now() + " | Current price = " + currentPrice + "\n");

  for (Iterator it = pricesToWatch.iterator(); it.hasNext();) {
    Price priceToWatch = it.next();

    if (priceToWatch.type.reached(currentPrice, priceToWatch.target)) {
      String message = priceToWatch.type.msg(currentPrice, priceToWatch.target);
      System.out.println(message); 
      displayNotification("Bitcoin Watcher", message);
      // remove from list to watch
      it.remove();
    }

  }
}

public void displayNotification(String title, String message) {
  if (SystemTray.isSupported()) {
    //Obtain only one instance of the SystemTray object
    SystemTray tray = SystemTray.getSystemTray();
    Image image = Toolkit.getDefaultToolkit().createImage("icon.png");
    TrayIcon trayIcon = new TrayIcon(image, "Bitcoin Watcher Notif");
    trayIcon.setImageAutoSize(true);
    trayIcon.setToolTip("Bitcoin Watcher");
  
    try {
      tray.add(trayIcon);
    } catch (AWTException e) {}

    trayIcon.displayMessage(title, message, MessageType.INFO);
  } else {
    System.err.println("System tray not supported!");
  }
}