我需要从另一个类

Question

调用一个方法//这里是我的代码：

Main Class: 

import java.awt.*; 
import java.awt.image.BufferedImage; 
import java.awt.image.DataBufferInt; 
import java.awt.image.BufferStrategy; 
import javax.swing.JFrame; 
public class Display extends Canvas implements Runnable{ 
    Toolkit toolkit = Toolkit.getDefaultToolkit(); 
    Dimension dim = toolkit.getScreenSize(); 
    public static int WIDTH; 
    public static int HEIGHT; 
    public static final String title = "First Person Game"; 
    public static Thread thread; 
    public static Screen screen; 
    public static BufferedImage img; 
    public static boolean running = false; 
    public static int[] pixels; 
    public static Render render; 
    public Display(){ 
     WIDTH = dim.width; 
     HEIGHT = dim.height; 
     screen = new Screen(WIDTH, HEIGHT); 
     img = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB); 
     pixels = ((DataBufferInt)img.getRaster().getDataBuffer()).getData(); 
    } 
    private void start(){ 
     if(running){ 
      return; 
     }else{ 
      running = true; 
      thread = new Thread(this); 
      thread.start(); 
     } 
    } 
    private void stop(){ 
     if(!running){ 
      return; 
     }else{ 
      running = false; 
      try{ 
       thread.join(); 
      }catch(Exception x){ 
       System.exit(0); 
      } 
     } 
    } 
    public void run(){ 
     while(running){ 
      render(); 
     } 
    } 
    public void render(){ 
     BufferStrategy bs = this.getBufferStrategy(); 
     if(bs == null){ 
      createBufferStrategy(3); 
      return; 
     } 
     screen.render(); 
     for(int i = 0; i < WIDTH * HEIGHT; i++){ 
      pixels[i] = screen.pixels[i]; 
     } 
     Graphics g = bs.getDrawGraphics(); 
     g.drawImage(img, 0, 0, WIDTH, HEIGHT, null); 
     g.dispose(); 
     bs.show(); 
    } 
    public static void main(String args[]){ 
     JFrame frame = new JFrame(); 
     BufferedImage cursorImg = new BufferedImage(16, 16, BufferedImage.TYPE_INT_ARGB); 
     Cursor blankCursor = Toolkit.getDefaultToolkit().createCustomCursor(cursorImg, new Point(0, 0), "blank cursor"); 
     frame.getContentPane().setCursor(blankCursor); 
     Display game = new Display(); 
     frame.setUndecorated(true); 
     frame.add(game); 
     frame.setTitle(title); 
     frame.pack(); 
     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
     frame.setSize(WIDTH, HEIGHT); 
     frame.setLocationRelativeTo(null); 
     frame.setResizable(false); 
     frame.setVisible(true); 
     fps f = new fps(); 
     game.start(); 
    } 
} 



The class I need to call: 

public class fps{ 
    public void fps(){ 
     System.out.println("Test 1 successful."); 
     int frames = 0; 
     double unprocessedSeconds = 0; 
     long previousTime = System.nanoTime(); 
     double secondsPerTick = 1/60.0; 
     int tickCount = 0; 
     boolean ticked = false; 
     Display c = new Display(); 
     System.out.println("Test 2 successful."); 
     c.render(); 
     long currentTime = System.nanoTime(); 
     long passedTime = currentTime - previousTime; 
     previousTime = currentTime; 
     unprocessedSeconds += passedTime/1000000000.0; 
     while(unprocessedSeconds > secondsPerTick){ 
      System.out.println("Test 3 successful."); 
      tick(); 
      unprocessedSeconds -= secondsPerTick; 
      ticked = true; 
      tickCount++; 
      if(tickCount % 60 == 0){ 
       System.out.println(frames + " fps"); 
       previousTime += 1000; 
       frames = 0; 
      } 
     } 
     if(ticked){ 
      c.render(); 
      frames++; 
     } 
     c.render(); 
     frames++; 
    } 
    public void tick(){} 
} 

/*我不知道如何做到这一点，我一直在尝试各种各样的事情。我基本上需要*来确保fps在显示运行时正在打印到控制台中。我似乎无法如此* /这。我尝试了run（）方法，但它不会调用它。

Answer 1

我相信你需要在你的主类中创建一个fps类的实例，然后通过它调用该方法。

fps nameOfClassInstance = new fps(//don't forget anything you need to send for constructor); 
fps.run(); 

至少这是怎么在C＃中，我知道是非常类似于java。

如果这没有帮助，那么我相信它是一个线程问题，并且您需要确保您正确地处理线程。 （我无法帮助解决这个问题，我对Java线程仍然很陌生。）

Answer 2

那么，你可以做两件事之一。您可以声明FPS对象：

fps myfps = new fps(); 
myfps.fps(); 

或者你可以把它所有的静态：

public static void fps(){ 
    ... 
} 
public static void tick(){} 

//elsewhere 
fps.fps() 

Answer 3

这是一个有点陌生，具有相同的名称为您的类中的方法。它是否意味着像这样构造？

public class fps{ 
    //Note that the void is removed here 
    public fps(){ 
     System.out.println("Test 1 successful."); 
     int frames = 0; 
     double unprocessedSeconds = 0; 
     long previousTime = System.nanoTime(); 
     double secondsPerTick = 1/60.0; 
     int tickCount = 0; 
     boolean ticked = false; 
     Display c = new Display(); 
     System.out.println("Test 2 successful."); 
     c.render(); 
     long currentTime = System.nanoTime(); 
     long passedTime = currentTime - previousTime; 
     previousTime = currentTime; 
     unprocessedSeconds += passedTime/1000000000.0; 
     while(unprocessedSeconds > secondsPerTick){ 
      System.out.println("Test 3 successful."); 
      tick(); 
      unprocessedSeconds -= secondsPerTick; 
      ticked = true; 
      tickCount++; 
      if(tickCount % 60 == 0){ 
       System.out.println(frames + " fps"); 
       previousTime += 1000; 
       frames = 0; 
      } 
     } 
     if(ticked){ 
      c.render(); 
      frames++; 
     } 
     c.render(); 
     frames++; 
    } 
    public void tick(){} 
} 

我也建议所有的代码不适合构造函数，应该移到它自己的方法。然后，如其他人所述，您可以在第一个之后创建一个fps对象，然后调用您的方法。

Answer 4

有在你的代码中的错误：

private void start(){ 
    if(running){ 
     return; 
    }else{ 
     running = true; 
     thread = new Thread(this); 
     thread.start(); 
    } 
} 

线程是通过调用start方法开始。你所做的是改变start（）方法。您应该使用run方法而不是start方法，因为Thread.start（）用于启动线程，而run（）则是您应该放置执行代码的位置。

由于从Java API的JavaDoc中，http://docs.oracle.com/javase/6/docs/api/java/lang/Thread.html#start%28%29

公共无效的start（）

Causes this thread to begin execution; the Java Virtual Machine calls the run method of this thread.