ReferenceNode.java

package edu.udel.cis.vsl.tass.ast.impl;

import java.util.NoSuchElementException;

import edu.udel.cis.vsl.tass.ast.IF.ASTNodeIF;
import edu.udel.cis.vsl.tass.ast.IF.IdentifierNodeIF;
import edu.udel.cis.vsl.tass.ast.IF.ReferenceNodeIF;

/**
 * A generic reference to another AST node.
 * 
 * @author Timothy K. Zirkel
 * 
 */
public class ReferenceNode extends ASTNode implements ReferenceNodeIF {

	private IdentifierNodeIF name;
	private ASTNodeIF referent;

	public ReferenceNode(long id) {
		super(id);
	}
	
	/**
	 * A reference to another AST node. The parameter name is the name of this
	 * reference. The parameter referent is the node referenced by this
	 * reference.
	 */
	public ReferenceNode(long id, IdentifierNodeIF name, ASTNodeIF referent) {
		super(id);
		this.name = name;
		this.referent = referent;
	}

	@Override
	public String name() {
		return name.name();
	}

	@Override
	public void setName(String name) {
		this.name.setName(name);
	}

	@Override
	public int numChildren() {
		return 2;
	}

	@Override
	public ASTNodeIF child(int index) throws NoSuchElementException {
		if (index == 0) {
			return name;
		} else if (index == 1) {
			return referent;
		} 
		throw new NoSuchElementException("Node " + id()
				+ " does not have a child with index " + index + ".");
	}

	@Override
	public void setChild(int i, ASTNodeIF child) throws NoSuchElementException {
		if (i == 0) {
			this.name = (IdentifierNodeIF) child;
		} else if (i == 1) {
			this.referent = child;
		}
		throw new NoSuchElementException("Node " + id()
				+ " does not have a child with index " + i + ".");
	}

	@Override
	public ASTNodeIF referent() {
		return referent;
	}

	@Override
	public void setReferent(ASTNodeIF referent) {
		this.referent = referent;
	}

}