Source for java.awt.font.TransformAttribute

   1: /* TransformAttribute.java --
   2:    Copyright (C) 2003, 2005  Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: 
  39: package java.awt.font;
  40: 
  41: import java.awt.geom.AffineTransform;
  42: import java.io.Serializable;
  43: 
  44: /**
  45:  * This class provides a mechanism for using an {@link AffineTransform} as
  46:  * an <i>immutable</i> attribute (for example, in the 
  47:  * {@link java.text.AttributedString} class).  Any transform passed to 
  48:  * this class is copied before being stored, and any transform handed out
  49:  * by this class is a copy of the stored transform.  In this way, it is 
  50:  * not possible to modify the stored transform.
  51:  * 
  52:  * @author Michael Koch
  53:  */
  54: public final class TransformAttribute implements Serializable
  55: {
  56:   private static final long serialVersionUID = 3356247357827709530L;
  57: 
  58:   private AffineTransform affineTransform;
  59:   
  60:   /**
  61:    * Creates a new attribute that contains a copy of the given transform.
  62:    * 
  63:    * @param transform  the transform (<code>null</code> not permitted).
  64:    * 
  65:    * @throws IllegalArgumentException if <code>transform</code> is 
  66:    *         <code>null</code>.
  67:    */
  68:   public TransformAttribute (AffineTransform transform) 
  69:   {
  70:     if (transform == null)
  71:       {
  72:         throw new IllegalArgumentException("Null 'transform' not permitted.");
  73:       }
  74:     this.affineTransform = new AffineTransform (transform);
  75:   }
  76: 
  77:   /**
  78:    * Returns a copy of the transform contained by this attribute.
  79:    * 
  80:    * @return A copy of the transform.
  81:    */
  82:   public AffineTransform getTransform ()
  83:   {
  84:     return (AffineTransform) affineTransform.clone();
  85:   }
  86: 
  87:   /**
  88:    * Returns <code>true</code> if the transform contained by this attribute is
  89:    * an identity transform, and <code>false</code> otherwise.
  90:    * 
  91:    * @return <code>true</code> if the transform contained by this attribute is
  92:    * an identity transform, and <code>false</code> otherwise.
  93:    * 
  94:    * @since 1.4
  95:    */
  96:   public boolean isIdentity ()
  97:   {
  98:     return (affineTransform == null ? false : affineTransform.isIdentity ());
  99:   }
 100: }