1   /*
    2    * Copyright (c) 2005, 2011, Oracle and/or its affiliates. All rights reserved.
    3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
    4    *
    5    * This code is free software; you can redistribute it and/or modify it
    6    * under the terms of the GNU General Public License version 2 only, as
    7    * published by the Free Software Foundation.  Oracle designates this
    8    * particular file as subject to the "Classpath" exception as provided
    9    * by Oracle in the LICENSE file that accompanied this code.
   10    *
   11    * This code is distributed in the hope that it will be useful, but WITHOUT
   12    * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   13    * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   14    * version 2 for more details (a copy is included in the LICENSE file that
   15    * accompanied this code).
   16    *
   17    * You should have received a copy of the GNU General Public License version
   18    * 2 along with this work; if not, write to the Free Software Foundation,
   19    * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   20    *
   21    * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   22    * or visit www.oracle.com if you need additional information or have any
   23    * questions.
   24    */
   25   
   26   package javax.lang.model.element;
   27   
   28   import javax.lang.model.type.TypeMirror;
   29   import javax.lang.model.util.Elements;
   30   
   31   /**
   32    * Represents a field, {@code enum} constant, method or constructor
   33    * parameter, local variable, resource variable, or exception
   34    * parameter.
   35    *
   36    * @author Joseph D. Darcy
   37    * @author Scott Seligman
   38    * @author Peter von der Ahé
   39    * @since 1.6
   40    */
   41   public interface VariableElement extends Element {
   42   
   43       /**
   44        * Returns the value of this variable if this is a {@code final}
   45        * field initialized to a compile-time constant.  Returns {@code
   46        * null} otherwise.  The value will be of a primitive type or a
   47        * {@code String}.  If the value is of a primitive type, it is
   48        * wrapped in the appropriate wrapper class (such as {@link
   49        * Integer}).
   50        *
   51        * <p>Note that not all {@code final} fields will have
   52        * constant values.  In particular, {@code enum} constants are
   53        * <em>not</em> considered to be compile-time constants.  To have a
   54        * constant value, a field's type must be either a primitive type
   55        * or {@code String}.
   56        *
   57        * @return the value of this variable if this is a {@code final}
   58        * field initialized to a compile-time constant, or {@code null}
   59        * otherwise
   60        *
   61        * @see Elements#getConstantExpression(Object)
   62        * @jls 15.28 Constant Expression
   63        * @jls 4.12.4 final Variables
   64        */
   65       Object getConstantValue();
   66   }