Source for java.lang.reflect.ParameterizedType

   1: /* ParameterizedType.java -- Represents parameterized types e.g. List<String>
   2:    Copyright (C) 2004, 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.lang.reflect;
  40: 
  41: /**
  42:  * <p>
  43:  * Represents a type which is parameterized over one or more other
  44:  * types.  For example, <code>List&lt;Integer&gt;</code> is a parameterized
  45:  * type, with <code>List</code> parameterized over the type
  46:  * <code>Integer</code>.
  47:  * </p>
  48:  * <p>
  49:  * Instances of this classes are created as needed, during reflection.
  50:  * On creating a parameterized type, <code>p</code>, the
  51:  * <code>GenericTypeDeclaration</code> corresponding to <code>p</code>
  52:  * is created and resolved.  Each type argument of <code>p</code>
  53:  * is then created recursively; details of this process are availble
  54:  * in the documentation of <code>TypeVariable</code>.  This creation
  55:  * process only happens once; repetition has no effect.
  56:  * </p>
  57:  * <p>
  58:  * Implementors of this interface must implement an appropriate
  59:  * <code>equals()</code> method.  This method should equate any
  60:  * two instances of the implementing class that have the same
  61:  * <code>GenericTypeDeclaration</code> and <code>Type</code>
  62:  * parameters.
  63:  *
  64:  * @author Tom Tromey (tromey@redhat.com)
  65:  * @author Andrew John Hughes (gnu_andrew@member.fsf.org)
  66:  * @see GenericDeclaration
  67:  * @see TypeVariable
  68:  * @since 1.5
  69:  */
  70: public interface ParameterizedType
  71:   extends Type
  72: {
  73: 
  74:   /**
  75:    * <p>
  76:    * Returns an array of <code>Type</code> objects, which gives
  77:    * the parameters of this type.
  78:    * </p>
  79:    * <p>
  80:    * <strong>Note</code>: the returned array may be empty.  This
  81:    * occurs if the supposed <code>ParameterizedType</code> is simply
  82:    * a normal type wrapped inside a parameterized type.
  83:    * </p>
  84:    *
  85:    * @return an array of <code>Type</code>s, representing the arguments
  86:    *         of this type.
  87:    * @throws TypeNotPresentException if any of the types referred to by
  88:    *         the parameters of this type do not actually exist.
  89:    * @throws MalformedParameterizedTypeException if any of the types
  90:    *         refer to a type which can not be instantiated.
  91:    */
  92:   Type[] getActualTypeArguments();
  93: 
  94:   /**
  95:    * Returns the type of which this type is a member.  For example,
  96:    * in <code>Top&lt;String&gt;.Bottom&lt;Integer&gt;</code>,
  97:    * <code>Bottom&lt;Integer&gt;</code> is a member of
  98:    * <code>Top&lt;String&gt;</code>, and so the latter is returned
  99:    * by this method.  Calling this method on top-level types (such as
 100:    * <code>Top&lt;String&gt;</code>) returns null.
 101:    *
 102:    * @return the type which owns this type.
 103:    * @throws TypeNotPresentException if the owner type referred to by
 104:    *         this type do not actually exist.
 105:    * @throws MalformedParameterizedTypeException if the owner type
 106:    *         referred to by this type can not be instantiated.
 107:    */
 108:   Type getOwnerType();
 109: 
 110:   /**
 111:    * Returns a version of this type without parameters, which corresponds
 112:    * to the class or interface which declared the type.  For example,
 113:    * the raw type corresponding to <code>List&lt;Double&gt;</code>
 114:    * is <code>List</code>, which was declared by the <code>List</code>
 115:    * class.
 116:    *
 117:    * @return the raw variant of this type (i.e. the type without
 118:    *         parameters).
 119:    */
 120:   Type getRawType();
 121: 
 122: }