What is the meaning of this line?
<p>I am looking at a sample game project. Can you explain these lines:</p>

<pre><code>public static final int GAMEPAD_UP = 0x0040;
</code></pre>

<p>What is the use of <code>0x0040;</code>?</p>

<p>This is the full code: </p>

<pre><code>package com.androidemu;

public class Emulator {
    public static final int VIDEO_W = 240;
    public static final int VIDEO_H = 160;

    public static final int GAMEPAD_UP        = 0x0040;
    public static final int GAMEPAD_DOWN    = 0x0080;
    public static final int GAMEPAD_LEFT    = 0x0020;
    public static final int GAMEPAD_RIGHT    = 0x0010;
    public static final int GAMEPAD_A        = 0x0001;
    public static final int GAMEPAD_B        = 0x0002;
    public static final int GAMEPAD_SELECT    = 0x0004;
    public static final int GAMEPAD_START    = 0x0008;
    public static final int GAMEPAD_TL        = 0x0200;
    public static final int GAMEPAD_TR        = 0x0100;

    public static final int GAMEPAD_A_TURBO    = (GAMEPAD_A &lt;&lt; 16);
    public static final int GAMEPAD_B_TURBO    = (GAMEPAD_B &lt;&lt; 16);

    public static final int GAMEPAD_UP_LEFT = (GAMEPAD_UP | GAMEPAD_LEFT);
    public static final int GAMEPAD_UP_RIGHT = (GAMEPAD_UP | GAMEPAD_RIGHT);
    public static final int GAMEPAD_DOWN_LEFT = (GAMEPAD_DOWN | GAMEPAD_LEFT);
    public static final int GAMEPAD_DOWN_RIGHT = (GAMEPAD_DOWN | GAMEPAD_RIGHT);

    public native void setRenderSurface(EmulatorView surface,
            int width, int height);
    public native void setKeyStates(int states);
    public native void setOption(String name, String value);

    public native boolean initialize(String libdir, String datadir);
    public native void cleanUp();
    public native void reset();
    public native void power();
    public native boolean loadBIOS(String file);
    public native boolean loadROM(String file);
    public native void unloadROM();
    public native void pause();
    public native void resume();
    public native void run();
    public native boolean saveState(String file);
    public native boolean loadState(String file);

    public void setOption(String name, boolean value) {
        setOption(name, value ? "true" : "false");
    }

    static {
        System.loadLibrary("gba");
    }
}
</code></pre>

<p>What are the purpose of these values? </p>
