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 java.io.InputStream;
  import java.io.InputStreamReader;
  import java.io.Reader;
  
  /**
   * Abstract base class for {@link ISourceFileLocator} locator implementations
   * based on {@link InputStream}s. It handles the encoding and tab width.
   */
  public abstract class InputStreamSourceFileLocator implements
  		ISourceFileLocator {
  
  	private final String encoding;
  	private final int tabWidth;
  
  	/**
  	 * Creates a new locator with the given specification.
  	 * 
  	 * @param encoding
  	 *            encoding of the source files, <code>null</code> for platform
  	 *            default encoding
  	 * @param tabWidth
  	 *            tab width in source files as number of blanks
  	 * 
  	 */
  	protected InputStreamSourceFileLocator(final String encoding,
  			final int tabWidth) {
  		this.encoding = encoding;
  		this.tabWidth = tabWidth;
  	}
  
  	public Reader getSourceFile(final String packageName, final String fileName)
  			throws IOException {
  		final InputStream in;
  		if (packageName.length() > 0) {
  			in = getSourceStream(packageName + "/" + fileName);
  		} else {
  			in = getSourceStream(fileName);
  		}
  
  		if (in == null) {
  			return null;
  		}
  
  		if (encoding == null) {
  			return new InputStreamReader(in);
  		} else {
  			return new InputStreamReader(in, encoding);
  		}
  	}
  
  	public int getTabWidth() {
  		return tabWidth;
  	}
  
  	/**
  	 * Tries to locate the given source file and opens its binary content.
  	 * 
  	 * @param path
  	 *            local path to the resource
  	 * @return stream if the file could be located, <code>null</code> otherwise
  	 * @throws IOException
  	 *             in case of problems while opening the stream
  	 */
  	protected abstract InputStream getSourceStream(String path)
  			throws IOException;
  
  }
  