Preconditions.java

/**
 *  @author Clément Petit (282626)
 *  @author Yanis Berkani (271348)
 */

package ch.epfl.gameboj;

public interface Preconditions {

    /**
     * throws the exception IllegalArgumentException if its argument is false do
     * nothing otherwise.
     * 
     * @param b
     *            the condition
     * @throws IllegalArgumentException
     *             if the argument is false
     */
    public static void checkArgument(boolean b) {
        if (!b) {
            throw new IllegalArgumentException();
        }
    }

    /**
     * return the argument if it is included between 0 and FF.
     * 
     * @param v
     *            the integer checked (must be included between 0 and FF)
     * @throws IllegalArgumentException
     *             if the argument is invalid
     * @return the argument
     */
    public static int checkBits8(int v) {
        checkArgument(v >= 0 && v <= 0xFF);
        return v;
    }

    /**
     * return the argument if it is included between 0 and FFFF.
     * 
     * @param v
     *            the integer checked (must be included between 0 and FFFF)
     * @throws IllegalArgumentException
     *             if the argument is invalid
     * @return the argument
     */
    public static int checkBits16(int v) {
        checkArgument(v >= 0 && v <= 0xFFFF);
        return v;
    }

}