Source for gnu.javax.net.ssl.provider.Constructed

   1: /* Constructed.java -- Constructed type.
   2:    Copyright (C) 2006  Free Software Foundation, Inc.
   3: 
   4: This file is a 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 of the License, or (at
   9: your option) 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; if not, write to the Free Software
  18: Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301
  19: 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 gnu.javax.net.ssl.provider;
  40: 
  41: /**
  42:  * The base interface to SSL constructed types.
  43:  *
  44:  * <p><b>Contract for ByteBuffer-based constructed types:</b>
  45:  *
  46:  * <p>Most implementations of this interface supported by this library
  47:  * take a "view" of an underlying ByteBuffer. The general contract of
  48:  * such classes is that they <em>will not</em> modify the position or
  49:  * limit of the buffer when doing read operations. That is, the position
  50:  * of the underlying buffer <em>should</em> remain at 0 throughout the
  51:  * lifetime of the object, and the limit should be either set to the
  52:  * capacity of the buffer, or to the size of the object (in most cases,
  53:  * the length of the protocol object is determined by the contents of
  54:  * the object, so the limit isn't useful in such cases. Of course, if the
  55:  * limit is set to something other than the object's length, it must be
  56:  * larger than the object length).
  57:  *
  58:  * <p>Setter methods (usually in a class that implements the {@link Builder}
  59:  * interface) may modify the limit, but the general contract remains that
  60:  * the position remain at zero, and that the limit be at least as large as
  61:  * the object length.
  62:  *
  63:  * <p>Thus, very often the code will use <em>absolute</em> getters and setters
  64:  * for primitive types, or it will use the {@link java.nio.ByteBuffer#duplicate()}
  65:  * method, and sometimes the {@link java.nio.ByteBuffer#slice()} method, and
  66:  * will change the position or limit of the duplicate buffer.
  67:  */
  68: public interface Constructed
  69: {
  70:   /**
  71:    * Returns the total length, in bytes, of this structure.
  72:    *
  73:    * @return The length of this structure.
  74:    */
  75:   int length();
  76: 
  77:   /**
  78:    * Returns a printable representation of this structure, with the
  79:    * given prefix prepended to each line.
  80:    *
  81:    * @param prefix The prefix to prepend to each line of the
  82:    * output. This value may be <code>null</code>.
  83:    * @return A printable representation of this structure.
  84:    */
  85:   String toString(String prefix);
  86: }