////////////////////////////////////////////////////////////////////////////////
   // checkstyle: Checks Java source code for adherence to a set of rules.
   // Copyright (C) 2001-2019 the original author or authors.
   //
   // 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.sizes;
  
  import com.puppycrawl.tools.checkstyle.StatelessCheck;
  import com.puppycrawl.tools.checkstyle.api.AbstractCheck;
  import com.puppycrawl.tools.checkstyle.api.DetailAST;
  import com.puppycrawl.tools.checkstyle.api.TokenTypes;
  import com.puppycrawl.tools.checkstyle.utils.AnnotationUtil;
  import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
  
  /**
   * <p>
   * Checks the number of parameters that a method or constructor has.
   * The default allowable number of parameters is 7.
   * To change the number of allowable parameters, set property max.
   * Allows to ignore number of parameters for methods with
   * &#064;{@link Override} annotation.
   * </p>
   * <p>
   * An example of how to configure the check is:
   * </p>
   * <pre>
   * &lt;module name="ParameterNumber"/&gt;
   * </pre>
   * <p>
   * An example of how to configure the check to allow 10 parameters
   * and ignoring parameters for methods with &#064;{@link Override}
   * annotation is:
   * </p>
   * <pre>
   * &lt;module name="ParameterNumber"&gt;
   *    &lt;property name="max" value="10"/&gt;
   *    &lt;property name="ignoreOverriddenMethods" value="true"/&gt;
   * &lt;/module&gt;
   * </pre>
   * Java code that will be ignored:
   * <pre>
   * {@code
   *
   *  &#064;Override
   *  public void needsLotsOfParameters(int a,
   *      int b, int c, int d, int e, int f, int g, int h) {
   *      ...
   *  }
   * }
   * </pre>
   */
  @StatelessCheck
  public class ParameterNumberCheck
      extends AbstractCheck {
  
      /**
       * A key is pointing to the warning message text in "messages.properties"
       * file.
       */
      public static final String MSG_KEY = "maxParam";
  
      /** {@link Override Override} annotation name. */
      private static final String OVERRIDE = "Override";
  
      /** Canonical {@link Override Override} annotation name. */
      private static final String CANONICAL_OVERRIDE = "java.lang." + OVERRIDE;
  
      /** Default maximum number of allowed parameters. */
      private static final int DEFAULT_MAX_PARAMETERS = 7;
  
      /** The maximum number of allowed parameters. */
      private int max = DEFAULT_MAX_PARAMETERS;
  
      /** Ignore overridden methods. */
      private boolean ignoreOverriddenMethods;
  
      /**
       * Sets the maximum number of allowed parameters.
       * @param max the max allowed parameters
       */
      public void setMax(int max) {
          this.max = max;
      }
  
      /**
      * Ignore number of parameters for methods with
      * &#064;{@link Override} annotation.
      * @param ignoreOverriddenMethods set ignore overridden methods
      */
     public void setIgnoreOverriddenMethods(boolean ignoreOverriddenMethods) {
         this.ignoreOverriddenMethods = ignoreOverriddenMethods;
     }
 
     @Override
     public int[] getDefaultTokens() {
         return getAcceptableTokens();
     }
 
     @Override
     public int[] getAcceptableTokens() {
         return new int[] {TokenTypes.METHOD_DEF, TokenTypes.CTOR_DEF};
     }
 
     @Override
     public int[] getRequiredTokens() {
         return CommonUtil.EMPTY_INT_ARRAY;
     }
 
     @Override
     public void visitToken(DetailAST ast) {
         final DetailAST params = ast.findFirstToken(TokenTypes.PARAMETERS);
         final int count = params.getChildCount(TokenTypes.PARAMETER_DEF);
         if (count > max && !shouldIgnoreNumberOfParameters(ast)) {
             final DetailAST name = ast.findFirstToken(TokenTypes.IDENT);
             log(name, MSG_KEY, max, count);
         }
     }
 
     /** Determine whether to ignore number of parameters for the method.
      *
      * @param ast the token to process
      * @return true if this is overridden method and number of parameters should be ignored
      *         false otherwise
      */
     private boolean shouldIgnoreNumberOfParameters(DetailAST ast) {
         //if you override a method, you have no power over the number of parameters
         return ignoreOverriddenMethods
                 && (AnnotationUtil.containsAnnotation(ast, OVERRIDE)
                 || AnnotationUtil.containsAnnotation(ast, CANONICAL_OVERRIDE));
     }
 
 }