////////////////////////////////////////////////////////////////////////////////

 // checkstyle: Checks Java source code for adherence to a set of rules.

 // Copyright (C) 2001-2014  Oliver Burn

 //

 // This library is free software; you can redistribute it and/or

 // modify it under the terms of the GNU Lesser General Public

 // License as published by the Free Software Foundation; either

 // version 2.1 of the License, or (at your option) any later version.

 //

 // This library 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

 // Lesser General Public License for more details.

 //

 // You should have received a copy of the GNU Lesser General Public

 // License along with this library; if not, write to the Free Software

 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 ////////////////////////////////////////////////////////////////////////////////

 package com.puppycrawl.tools.checkstyle.checks.naming;

 import com.puppycrawl.tools.checkstyle.api.DetailAST;

 import com.puppycrawl.tools.checkstyle.api.ScopeUtils;

 import com.puppycrawl.tools.checkstyle.api.TokenTypes;

 /**

  * <p>

  * Checks that constant names conform to a format specified

  * by the format property.

  * A <em>constant</em> is a <strong>static</strong> and <strong>final</strong>

  * field or an interface/annotation field, except

  * <strong>serialVersionUID</strong> and <strong>serialPersistentFields

  * </strong>.  The format is a regular expression

  * and defaults to <strong>^[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$</strong>.

  * </p>

  * <p>

  * An example of how to configure the check is:

  * </p>

  * <pre>

  * <module name="ConstantName"/>

  * </pre>

  *

  * <p>

  * An example of how to configure the check for names that are only upper case

  * letters and digits is:

  * </p>

  * <pre>

  * <module name="ConstantName">

  *    <property name="format" value="^[A-Z][A-Z0-9]*$"/>

  * </module>

  * </pre>

  *

  *

  * @author Rick Giles

  * @version 1.0

  */

 public class ConstantNameCheck

     extends AbstractAccessControlNameCheck

 {

     /** Creates a new <code>ConstantNameCheck</code> instance. */

     public ConstantNameCheck()

     {

         super("^[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$");

     }

     @Override

     public int[] getDefaultTokens()

     {

         return new int[] {TokenTypes.VARIABLE_DEF};

     }

     @Override

     protected final boolean mustCheckName(DetailAST aAST)

     {

         boolean retVal = false;

         final DetailAST modifiersAST =

             aAST.findFirstToken(TokenTypes.MODIFIERS);

         final boolean isStatic = (modifiersAST != null)

             && modifiersAST.branchContains(TokenTypes.LITERAL_STATIC);

         final boolean isFinal = (modifiersAST != null)

             && modifiersAST.branchContains(TokenTypes.FINAL);

         if ((isStatic  && isFinal && shouldCheckInScope(modifiersAST))

             || ScopeUtils.inInterfaceOrAnnotationBlock(aAST))

         {

             // Handle the serialVersionUID and serialPersistentFields  constants

             // which are used for Serialization. Cannot enforce rules on it. :-)

             final DetailAST nameAST = aAST.findFirstToken(TokenTypes.IDENT);

             if ((nameAST != null)

                 && !("serialVersionUID".equals(nameAST.getText()))

                 && !("serialPersistentFields".equals(nameAST.getText())))

             {

                 retVal = true;

             }

         }

         return retVal;

     }

 }