Slick2d图像对象无法正确显示？

Question

I just started using the Slick2d game library (following this guide). For some reason the whole frame is black. I don't know what's wrong, because I'm getting complaints from neither Eclipse nor Slick2d.

Here is a screenshot of my project tree:

Here is the Game.java source:

package com.michael.ivorymoon;

import org.newdawn.slick.AppGameContainer;
import org.newdawn.slick.BasicGame;
import org.newdawn.slick.GameContainer;
import org.newdawn.slick.Graphics;
import org.newdawn.slick.Image;
import org.newdawn.slick.SlickException;

public class Game extends BasicGame
{
    Image land = null;
    Image plane = null;
    float x = 400;
    float y = 300;
    float scale = 1.0f;

    public Game()
    {
        super("Ivory Moon");
    }

    @Override
    public void init(GameContainer container) throws SlickException
    {
        land = new Image("/res/land.jpg");
        land.draw(0, 0);
        plane = new Image("/res/plane.png");
        plane.draw(x, y, scale);
    }

    @Override
    public void update(GameContainer container, int delta) throws SlickException
    {
        ;
    }

    @Override
    public void render(GameContainer container, Graphics graphics) throws SlickException
    {
        ;       
    }

    public static void main(String[] args) throws SlickException
    {
        AppGameContainer appContainer = new AppGameContainer(new Game());

        appContainer.setDisplayMode(800, 600, false);
        appContainer.start();
    }
}

You can find /res/land.jpg over here . This is /res/plane.jpg :

And finally, just in case you didn't believe me, here is the running application:

Answer 1

 land = new Image("/res/land.jpg");

and

 land = new Image("/res/plane.png");

are the culprit, the leading / states you want to start at the base of your filesystem, an absolute path. Try using:

 land = new Image("res/land.jpg");
 land = new Image("res/plane.png");

This path is relative to your project, should work.

Also, draw calls need to be made within render method.