src/java.compiler/share/classes/javax/lang/model/type/TypeVariable.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * particular file as subject to the "Classpath" exception as provided
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 * 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,
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package javax.lang.model.type;


import javax.lang.model.element.Element;
import javax.lang.model.element.TypeParameterElement;
import javax.lang.model.util.Types;


/**
 * Represents a type variable.
 * A type variable may be explicitly declared by a
 * {@linkplain TypeParameterElement type parameter} of a
 * type, method, or constructor.
 * A type variable may also be declared implicitly, as by
 * the capture conversion of a wildcard type argument
 * (see chapter 5 of
 * <cite>The Java&trade; Language Specification</cite>).
 *
 * @author Joseph D. Darcy
 * @author Scott Seligman
 * @author Peter von der Ah&eacute;
 * @see TypeParameterElement
 * @since 1.6
 */
public interface TypeVariable extends ReferenceType {

    /**
     * Returns the element corresponding to this type variable.
     *
     * @return the element corresponding to this type variable
     */
    Element asElement();

    /**
     * Returns the upper bound of this type variable.
     *
     * <p> If this type variable was declared with no explicit
     * upper bounds, the result is {@code java.lang.Object}.
     * If it was declared with multiple upper bounds,
     * the result is an {@linkplain IntersectionType intersection type};
     * individual bounds can be found by examining the result's
     * {@linkplain IntersectionType#getBounds() bounds}.
     *
     * @return the upper bound of this type variable
     */
    TypeMirror getUpperBound();

    /**
     * Returns the lower bound of this type variable.  While a type
     * parameter cannot include an explicit lower bound declaration,
     * capture conversion can produce a type variable with a
     * non-trivial lower bound.  Type variables otherwise have a
     * lower bound of {@link NullType}.
     *
     * @return the lower bound of this type variable
     */
    TypeMirror getLowerBound();
}