content: /*******************************************************************************
   * Copyright (c) 2009, 2019 Mountainminds GmbH & Co. KG and Contributors
   * 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:
   *    Marc R. Hoffmann - initial API and implementation
   *    
   *******************************************************************************/
  package org.jacoco.report;
  
  import java.io.IOException;
  
  import org.jacoco.core.analysis.IBundleCoverage;
  
  /**
   * Output-Interface for hierarchical report structures. To allow sequential
   * processing and save memory the group structure has to be traversed in a
   * "deep first" fashion. The interface is implemented by the report formatters
   * and can be used to emit coverage report structures.
   * 
   * The following constraints apply in using {@link IReportGroupVisitor} instances:
   * 
   * <ul>
   * <li>A visitor instance can be used to either submit bundles (
   * {@link #visitBundle(IBundleCoverage, ISourceFileLocator)}) or groups
   * {@link #visitGroup(String)}). Bundles and groups are not allowed for the same
   * visitor.</li>
   * <li>When creating nested groups with {@link #visitGroup(String)} the
   * hierarchy has to be processed in a "deep first" manner.</li>
   * </ul>
   */
  public interface IReportGroupVisitor {
  
  	/**
  	 * Called to add a bundle to the the report.
  	 * 
  	 * @param bundle
  	 *            a bundle to include in the report
  	 * @param locator
  	 *            source locator for this bundle
  	 * @throws IOException
  	 *             in case of IO problems with the report writer
  	 */
  	void visitBundle(IBundleCoverage bundle, ISourceFileLocator locator)
  			throws IOException;
  
  	/**
  	 * Called to add a new group to the report. The returned
  	 * {@link IReportGroupVisitor} instance can be used to add nested bundles or
  	 * groups. The content of the group has to be completed before this or any
  	 * parent visitor can be used again ("deep first").
  	 * 
  	 * @param name
  	 *            name of the group
  	 * @return visitor for the group's content
  	 * @throws IOException
  	 *             in case of IO problems with the report writer
  	 */
  	IReportGroupVisitor visitGroup(String name) throws IOException;
  
  }
  