Basic tab-character handling stuff : String char « Data Type « Java

1. Java
2. Data Type
3. String char

Basic tab-character handling stuff

      
/*
 * Copyright (c) Ian F. Darwin, http://www.darwinsys.com/, 1996-2002.
 * All rights reserved. Software written by Ian F. Darwin and others.
 * $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * Java, the Duke mascot, and all variants of Sun's Java "steaming coffee
 * cup" logo are trademarks of Sun Microsystems. Sun's, and James Gosling's,
 * pioneering role in inventing and promulgating (and standardizing) the Java 
 * language and environment is gratefully acknowledged.
 * 
 * The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for
 * inventing predecessor languages C and C++ is also gratefully acknowledged.
 */


import junit.framework.TestCase;

/** Basic tab-character handling stuff.
 * <p>
 * N.B. Can only handle equally-spaced tab stops as written.
 * @author Ian F. Darwin, http://www.darwinsys.com/
 * @version $Id: Tabs.java,v 1.9 2004/02/28 02:48:15 ian Exp $
 */
public class Tabs {
  /** tabs every so often */
  public final static int DEFTABSPACE =   8;
  /** the current tab stop setting. */
  protected int tabSpace = DEFTABSPACE;
  /** The longest line that we initially set tabs for. */
  public final static int MAXLINE  = 255;
  /** the current tab stops */
  protected boolean[] tabstops;

  /** Construct a Tabs object with a given tab stop settings */
  public Tabs(int n) {
    if (n <= 0) {
      n = 1;
    }
    tabstops = new boolean[MAXLINE];
    tabSpace = n;
    settabs();
  }

  /** Construct a Tabs object with a default tab stop settings */
  public Tabs() {
    this(DEFTABSPACE);
  }

  /** settabs - set initial tab stops */
  private void settabs() {
    for (int i = 0; i < tabstops.length; i++) {
      tabstops[i] = ((i+1) % tabSpace) == 0;
    }
  }
  
  /**
   * @return Returns the tabSpace.
   */
  public int getTabSpacing() {
    return tabSpace;
  }
  
  /** isTabStop - returns true if given column is a tab stop.
   * @param col - the current column number
   */
  public boolean isTabStop(int col) {
    if (col > tabstops.length - 1) {
      tabstops = new boolean[tabstops.length * 2];
      settabs();
    }
    return tabstops[col];
  }
}



/**
 * @author ian
 *
 * To change the template for this generated type comment go to
 * Window - Preferences - Java - Code Generation - Code and Comments
 */
class TabsTest extends TestCase {

  public static void main(String[] args) {
    junit.textui.TestRunner.run(TabsTest.class);
  }

  private Tabs t4, t8;
  
  public void setUp() {
    t4 = new Tabs(4);
    t8 = new Tabs();
  }
  
  public void testGetTabSpacing() {
    assertEquals(t4.getTabSpacing(), 4);
    assertEquals(t8.getTabSpacing(), Tabs.DEFTABSPACE);
  }
  
  public  void testIsTabStop() {
    assertEquals(false, t4.isTabStop(0));
    assertEquals(false, t4.isTabStop(1));
    assertEquals(false, t4.isTabStop(2));
    assertEquals(true,  t4.isTabStop(3));
    assertEquals(false, t4.isTabStop(4));
    assertEquals(false, t4.isTabStop(5));
    assertEquals(false, t4.isTabStop(6));
    assertEquals(true,  t4.isTabStop(7));
    assertEquals(false, t4.isTabStop(8));
  }
}




           
         
    
    
    
    
    
  

Related examples in the same category