| /******************************************************************************* |
| * Copyright (c) 2005, 2006 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.jdt.internal.corext.refactoring.structure.constraints; |
| |
| import org.eclipse.core.runtime.Assert; |
| |
| import org.eclipse.jdt.internal.corext.refactoring.typeconstraints2.ConstraintVariable2; |
| import org.eclipse.jdt.internal.corext.refactoring.typeconstraints2.ITypeConstraint2; |
| |
| /** |
| * Type constraint which models covariance-related types. |
| */ |
| public final class CovariantTypeConstraint implements ITypeConstraint2 { |
| |
| /** The ancestor type */ |
| private final ConstraintVariable2 fAncestor; |
| |
| /** The descendant type */ |
| private final ConstraintVariable2 fDescendant; |
| |
| /** |
| * Creates a new covariant type constraint. |
| * |
| * @param descendant the descendant type |
| * @param ancestor the ancestor type |
| */ |
| public CovariantTypeConstraint(final ConstraintVariable2 descendant, final ConstraintVariable2 ancestor) { |
| Assert.isNotNull(descendant); |
| Assert.isNotNull(ancestor); |
| fDescendant= descendant; |
| fAncestor= ancestor; |
| } |
| |
| /* |
| * @see java.lang.Object#equals(java.lang.Object) |
| */ |
| public final boolean equals(final Object object) { |
| if (object.getClass() != CovariantTypeConstraint.class) |
| return false; |
| final ITypeConstraint2 other= (ITypeConstraint2) object; |
| return getLeft() == other.getLeft() && getRight() == other.getRight(); |
| } |
| |
| /* |
| * @see org.eclipse.jdt.internal.corext.refactoring.typeconstraints2.ITypeConstraint2#getLeft() |
| */ |
| public final ConstraintVariable2 getLeft() { |
| return fDescendant; |
| } |
| |
| /* |
| * @see org.eclipse.jdt.internal.corext.refactoring.typeconstraints2.ITypeConstraint2#getRight() |
| */ |
| public final ConstraintVariable2 getRight() { |
| return fAncestor; |
| } |
| |
| /* |
| * @see java.lang.Object#hashCode() |
| */ |
| public final int hashCode() { |
| return fDescendant.hashCode() ^ 35 * fAncestor.hashCode(); |
| } |
| |
| /* |
| * @see java.lang.Object#toString() |
| */ |
| public final String toString() { |
| return fDescendant.toString() + " <<= " + fAncestor.toString(); //$NON-NLS-1$ |
| } |
| } |