001/* ParameterizedType.java -- Represents parameterized types e.g. List<String> 002 Copyright (C) 2004, 2005 Free Software Foundation, Inc. 003 004This file is part of GNU Classpath. 005 006GNU Classpath is free software; you can redistribute it and/or modify 007it under the terms of the GNU General Public License as published by 008the Free Software Foundation; either version 2, or (at your option) 009any later version. 010 011GNU Classpath is distributed in the hope that it will be useful, but 012WITHOUT ANY WARRANTY; without even the implied warranty of 013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014General Public License for more details. 015 016You should have received a copy of the GNU General Public License 017along with GNU Classpath; see the file COPYING. If not, write to the 018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 01902110-1301 USA. 020 021Linking this library statically or dynamically with other modules is 022making a combined work based on this library. Thus, the terms and 023conditions of the GNU General Public License cover the whole 024combination. 025 026As a special exception, the copyright holders of this library give you 027permission to link this library with independent modules to produce an 028executable, regardless of the license terms of these independent 029modules, and to copy and distribute the resulting executable under 030terms of your choice, provided that you also meet, for each linked 031independent module, the terms and conditions of the license of that 032module. An independent module is a module which is not derived from 033or based on this library. If you modify this library, you may extend 034this exception to your version of the library, but you are not 035obligated to do so. If you do not wish to do so, delete this 036exception statement from your version. */ 037 038 039package java.lang.reflect; 040 041/** 042 * <p> 043 * Represents a type which is parameterized over one or more other 044 * types. For example, <code>List<Integer></code> is a parameterized 045 * type, with <code>List</code> parameterized over the type 046 * <code>Integer</code>. 047 * </p> 048 * <p> 049 * Instances of this classes are created as needed, during reflection. 050 * On creating a parameterized type, <code>p</code>, the 051 * <code>GenericTypeDeclaration</code> corresponding to <code>p</code> 052 * is created and resolved. Each type argument of <code>p</code> 053 * is then created recursively; details of this process are availble 054 * in the documentation of <code>TypeVariable</code>. This creation 055 * process only happens once; repetition has no effect. 056 * </p> 057 * <p> 058 * Implementors of this interface must implement an appropriate 059 * <code>equals()</code> method. This method should equate any 060 * two instances of the implementing class that have the same 061 * <code>GenericTypeDeclaration</code> and <code>Type</code> 062 * parameters. 063 * 064 * @author Tom Tromey (tromey@redhat.com) 065 * @author Andrew John Hughes (gnu_andrew@member.fsf.org) 066 * @see GenericDeclaration 067 * @see TypeVariable 068 * @since 1.5 069 */ 070public interface ParameterizedType 071 extends Type 072{ 073 074 /** 075 * <p> 076 * Returns an array of <code>Type</code> objects, which gives 077 * the parameters of this type. 078 * </p> 079 * <p> 080 * <strong>Note</code>: the returned array may be empty. This 081 * occurs if the supposed <code>ParameterizedType</code> is simply 082 * a normal type wrapped inside a parameterized type. 083 * </p> 084 * 085 * @return an array of <code>Type</code>s, representing the arguments 086 * of this type. 087 * @throws TypeNotPresentException if any of the types referred to by 088 * the parameters of this type do not actually exist. 089 * @throws MalformedParameterizedTypeException if any of the types 090 * refer to a type which can not be instantiated. 091 */ 092 Type[] getActualTypeArguments(); 093 094 /** 095 * Returns the type of which this type is a member. For example, 096 * in <code>Top<String>.Bottom<Integer></code>, 097 * <code>Bottom<Integer></code> is a member of 098 * <code>Top<String></code>, and so the latter is returned 099 * by this method. Calling this method on top-level types (such as 100 * <code>Top<String></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<Double></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}