jdk/src/share/classes/java/lang/reflect/ParameterizedType.java

/*
 * Copyright 2003-2004 Sun Microsystems, Inc.  All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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package java.lang.reflect;


/**
 * ParameterizedType represents a parameterized type such as
 * Collection<String>.
 *
 * <p>A parameterized type is created the first time it is needed by a
 * reflective method, as specified in this package. When a
 * parameterized type p is created, the generic type declaration that
 * p instantiates is resolved, and all type arguments of p are created
 * recursively. See {@link java.lang.reflect.TypeVariable
 * TypeVariable} for details on the creation process for type
 * variables. Repeated creation of a parameterized type has no effect.
 *
 * <p>Instances of classes that implement this interface must implement
 * an equals() method that equates any two instances that share the
 * same generic type declaration and have equal type parameters.
 *
 * @since 1.5
 */
public interface ParameterizedType extends Type {
    /**
     * Returns an array of {@code Type} objects representing the actual type
     * arguments to this type.
     *
     * <p>Note that in some cases, the returned array be empty. This can occur
     * if this type represents a non-parameterized type nested within
     * a parameterized type.
     *
     * @return an array of {@code Type} objects representing the actual type
     *     arguments to this type
     * @throws TypeNotPresentException if any of the
     *     actual type arguments refers to a non-existent type declaration
     * @throws MalformedParameterizedTypeException if any of the
     *     actual type parameters refer to a parameterized type that cannot
     *     be instantiated for any reason
     * @since 1.5
     */
    Type[] getActualTypeArguments();

    /**
     * Returns the {@code Type} object representing the class or interface
     * that declared this type.
     *
     * @return the {@code Type} object representing the class or interface
     *     that declared this type
     * @since 1.5
     */
    Type getRawType();

    /**
     * Returns a {@code Type} object representing the type that this type
     * is a member of.  For example, if this type is {@code O<T>.I<S>},
     * return a representation of {@code O<T>}.
     *
     * <p>If this type is a top-level type, {@code null} is returned.
     *
     * @return a {@code Type} object representing the type that
     *     this type is a member of. If this type is a top-level type,
     *     {@code null} is returned
     * @throws TypeNotPresentException if the owner type
     *     refers to a non-existent type declaration
     * @throws MalformedParameterizedTypeException if the owner type
     *     refers to a parameterized type that cannot be instantiated
     *     for any reason
     * @since 1.5
     */
    Type getOwnerType();
}