Function.java

package org.sinnlabs.dbvim.evaluator;

/** A <a href="http://en.wikipedia.org/wiki/Function_(mathematics)">function</a>.
 * @author Jean-Marc Astesana
 */
public class Function {
	private String name;
	private int minArgumentCount;
	private int maxArgumentCount;

	/** Constructor.
	 * <br>This constructor builds a function with a fixed arguments count.
	 * @param name The function's name
	 * @param argumentCount The function's argument count.
	 * @throws IllegalArgumentException if argumentCount is lower than 0 or if the function name is null or empty.
	 */
	public Function(String name, int argumentCount) {
		this(name, argumentCount, argumentCount);
	}

	/** Constructor.
	 * <br>This constructor builds a function with a variable arguments count.
	 * <br>For instance, a minimum function may have at least one argument.
	 * @param name The function's name
	 * @param minArgumentCount The function's minimum argument count.
	 * @param maxArgumentCount The function's maximum argument count (Integer.MAX_VALUE to specify no upper limit).
	 * @throws IllegalArgumentException if minArgumentCount is less than 0 or greater than maxArgumentCount or if the function name is null or empty.
	 */
	public Function(String name, int minArgumentCount, int maxArgumentCount) {
		if ((minArgumentCount<0) || (minArgumentCount>maxArgumentCount)) {
			throw new IllegalArgumentException("Invalid argument count");
		}
		if (name==null || name.length()==0) {
			throw new IllegalArgumentException("Invalid function name");
		}
		this.name = name;
		this.minArgumentCount = minArgumentCount;
		this.maxArgumentCount = maxArgumentCount;
	}

	/** Gets the function's name.
	 * @return the name of the function
	 */
	public String getName() {
		return this.name;
	}

	/** Gets the function's minimum argument count.
	 * @return an integer
	 */
	public int getMinimumArgumentCount() {
		return this.minArgumentCount;
	}

	/** Gets the function's maximum argument count.
	 * @return an integer
	 */
	public int getMaximumArgumentCount() {
		return this.maxArgumentCount;
	}
}