User32

package abendigo.mem.jna;

import com.sun.jna.Native;

/**
 * This direct-mapped JNA utility offers access to the <em>user32</em> module on <em>Windows</em>.
 *
 * @author Thomas G. P. Nappo (Jire)
 * @author Jonathan Beaudoin (Jonatino)
 */
public final class User32 {

	/**
	 * Determines whether a key is up or down at the time the function is called, and whether
	 * the key was pressed after a previous call to {@link #GetAsyncKeyState(int)}.
	 *
	 * @param vKey The virtual-key code.
	 * @return If the function succeeds, the return value specifies whether the key was pressed since
	 * the last call to <strong>GetAsyncKeyState</strong>, and whether the key is currently up or down.
	 * If the most significant bit is set, the key is down, and if the least significant bit is set,
	 * the key was pressed after the previous call to <strong>GetAsyncKeyState</strong>.
	 */
	public static native short GetAsyncKeyState(int vKey);

	/**
	 * Retrieves the status of the specified virtual key. The status specifies whether the key is
	 * up, down, or toggled (on, off—alternating each time the key is pressed).
	 *
	 * @param vKey A virtual key. If the desired virtual key is a letter or digit (A through Z, a through z, or 0 through 9),
	 *             this parameter must be set to the ASCII value of that character. For other keys, it must be a virtual-key code.<p />
	 *             If a non-English keyboard layout is used, virtual keys with values in the range ASCII A through Z and 0 through 9
	 *             are used to specify most of the character keys. For example, for the German keyboard layout, the virtual key of value
	 *             ASCII O (0x4F) refers to the "o" key, whereas VK_OEM_1 refers to the "o with umlaut" key.
	 * @return The return value specifies the status of the specified virtual key, as follows:<br />
	 * <ul>
	 * <li>If the high-order bit is 1, the key is down; otherwise, it is up.</li>
	 * <li>If the low-order bit is 1, the key is toggled. A key, such as the CAPS LOCK key, is toggled if it is turned on.
	 * The key is off and untoggled if the low-order bit is 0. A toggle key's indicator light (if any) on the keyboard will
	 * be on when the key is toggled, and off when the key is untoggled.</li>
	 * </ul>
	 */
	public static native short GetKeyState(int vKey);

	static {
		Native.register("User32");
	}

	private User32() {
	}

}