/*
 * Bytecode Analysis Framework
 * Copyright (C) 2003,2004 University of Maryland
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package edu.umd.cs.findbugs.ba.bcp;

import edu.umd.cs.findbugs.annotations.Nullable;
import edu.umd.cs.findbugs.ba.vna.ValueNumber;

public class FieldVariable implements Variable {
	private final ValueNumber ref;
	private final String className;
	private final String fieldName;
	private final String fieldSig;

	/**
	 * Constructor for static fields.
	 *
	 * @param className the class name
	 * @param fieldName the field name
	 * @param fieldSig  the field signature
	 */
	public FieldVariable(String className, String fieldName, String fieldSig) {
		this(null, className, fieldName, fieldSig);
	}

	/**
	 * Constructor for instance fields.
	 *
	 * @param ref       ValueNumber of the object reference
	 * @param className the class name
	 * @param fieldName the field name
	 * @param fieldSig  the field signature
	 */
	public FieldVariable(@Nullable ValueNumber ref, String className, String fieldName, String fieldSig) {
		this.ref = ref;
		this.className = className;
		this.fieldName = fieldName;
		this.fieldSig = fieldSig;
	}

	/**
	 * Return whether or not this is a static field.
	 */
	public boolean isStatic() {
		return ref == null;
	}

	/**
	 * Get the class name.
	 */
	public String getClassName() {
		return className;
	}

	/**
	 * Get the field name.
	 */
	public String getFieldName() {
		return fieldName;
	}

	/**
	 * Get the field signature.
	 */
	public String getFieldSig() {
		return fieldSig;
	}

	public boolean sameAs(Variable other) {
		if (!(other instanceof FieldVariable))
			return false;
		FieldVariable otherField = (FieldVariable) other;
		if (isStatic() != otherField.isStatic())
			return false;
		return (ref == null || ref.equals(otherField.ref))
				&& className.equals(otherField.className)
				&& fieldName.equals(otherField.fieldName)
				&& fieldSig.equals(otherField.fieldSig);
	}

	@Override
	public String toString() {
		StringBuilder buf = new StringBuilder();
		buf.append(className);
		buf.append('.');
		buf.append(fieldName);
		return buf.toString();
	}
}

// vim:ts=4
