/*
    * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org> and others
    *
    * This program and the accompanying materials are made available under the
    * terms of the Eclipse Distribution License v. 1.0 which is available at
    * https://www.eclipse.org/org/documents/edl-v10.php.
    *
    * SPDX-License-Identifier: BSD-3-Clause
    */
  
  package org.eclipse.jgit.revwalk.filter;
  
  import java.io.IOException;
  
  import org.eclipse.jgit.errors.IncorrectObjectTypeException;
  import org.eclipse.jgit.errors.MissingObjectException;
  import org.eclipse.jgit.revwalk.RevCommit;
  import org.eclipse.jgit.revwalk.RevWalk;
  
  /**
   * Includes a commit only if the subfilter does not include the commit.
   */
  public class NotRevFilter extends RevFilter {
  	/**
  	 * Create a filter that negates the result of another filter.
  	 *
  	 * @param a
  	 *            filter to negate.
  	 * @return a filter that does the reverse of <code>a</code>.
  	 */
  	public static RevFilter../../../../../org/eclipse/jgit/revwalk/filter/RevFilter.html#RevFilter">RevFilter create(RevFilter a) {
  		return new NotRevFilter(a);
  	}
  
  	private final RevFilter a;
  
  	private NotRevFilter(RevFilter one) {
  		a = one;
  	}
  
  	/** {@inheritDoc} */
  	@Override
  	public RevFilter negate() {
  		return a;
  	}
  
  	/** {@inheritDoc} */
  	@Override
  	public boolean include(RevWalk walker, RevCommit c)
  			throws MissingObjectException, IncorrectObjectTypeException,
  			IOException {
  		return !a.include(walker, c);
  	}
  
  	/** {@inheritDoc} */
  	@Override
  	public boolean requiresCommitBody() {
  		return a.requiresCommitBody();
  	}
  
  	/** {@inheritDoc} */
  	@Override
  	public RevFilter clone() {
  		return new NotRevFilter(a.clone());
  	}
  
  	/** {@inheritDoc} */
  	@Override
  	public String toString() {
  		return "NOT " + a.toString(); //$NON-NLS-1$
  	}
  }