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    1   /*
    2    * $Id: NewStaticMetaMethod.java 4550 2006-12-21 22:22:40Z blackdrag $
    3    *
    4    * Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
    5    *
    6    * Redistribution and use of this software and associated documentation
    7    * ("Software"), with or without modification, are permitted provided that the
    8    * following conditions are met:
    9    *  1. Redistributions of source code must retain copyright statements and
    10   * notices. Redistributions must also contain a copy of this document.
    11   *  2. Redistributions in binary form must reproduce the above copyright
    12   * notice, this list of conditions and the following disclaimer in the
    13   * documentation and/or other materials provided with the distribution.
    14   *  3. The name "groovy" must not be used to endorse or promote products
    15   * derived from this Software without prior written permission of The Codehaus.
    16   * For written permission, please contact info@codehaus.org.
    17   *  4. Products derived from this Software may not be called "groovy" nor may
    18   * "groovy" appear in their names without prior written permission of The
    19   * Codehaus. "groovy" is a registered trademark of The Codehaus.
    20   *  5. Due credit should be given to The Codehaus - http://groovy.codehaus.org/
    21   *
    22   * THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS ``AS IS'' AND ANY
    23   * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
    24   * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
    25   * DISCLAIMED. IN NO EVENT SHALL THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR
    26   * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
    27   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
    28   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
    29   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
    30   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
    31   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
    32   * DAMAGE.
    33   *
    34   */
    35  package org.codehaus.groovy.runtime;
    36
    37  import groovy.lang.MetaMethod;
    38
    39  /***
    40   * A MetaMethod implementation where the underlying method is really a static
    41   * helper method on some class.
    42   *
    43   * This implementation is used to add new static methods to the JDK writing them as normal
    44   * static methods with the first parameter being the class on which the method is added.
    45   *
    46   * @author Guillaume Laforge
    47   * @version $Revision: 4550 $
    48   */
    49  public class NewStaticMetaMethod extends MetaMethod {
    50
    51      private static final Class[] EMPTY_TYPE_ARRAY = {};
    52
    53      private MetaMethod metaMethod;
    54      private Class[] logicalParameterTypes;
    55
    56      public NewStaticMetaMethod(MetaMethod metaMethod) {
    57          super(metaMethod);
    58          this.metaMethod = metaMethod;
    59          init();
    60      }
    61
    62      public NewStaticMetaMethod(String name, Class declaringClass, Class[] parameterTypes, Class returnType, int modifiers) {
    63          super(name, declaringClass, parameterTypes, returnType, modifiers);
    64          this.metaMethod = new MetaMethod(name, declaringClass, parameterTypes,returnType, modifiers);
    65          init();
    66      }
    67
    68      private void init() {
    69          Class[] realParameterTypes = metaMethod.getParameterTypes();
    70          int size = realParameterTypes!=null ? realParameterTypes.length : 0;
    71          if (size <= 1) {
    72              logicalParameterTypes = EMPTY_TYPE_ARRAY;
    73          } else {
    74              logicalParameterTypes = new Class[--size];
    75              System.arraycopy(realParameterTypes, 1, logicalParameterTypes, 0, size);
    76          }
    77      }
    78
    79      public Class getDeclaringClass() {
    80          return getBytecodeParameterTypes()[0];
    81      }
    82
    83      public boolean isStatic() {
    84          return true;
    85      }
    86
    87      public int getModifiers() {
    88          return super.getModifiers();
    89      }
    90
    91      public Class[] getParameterTypes() {
    92          return logicalParameterTypes;
    93      }
    94
    95      public Class[] getBytecodeParameterTypes() {
    96          return super.getParameterTypes();
    97      }
    98
    99      public Object invoke(Object object, Object[] arguments) {
    100         int size = arguments.length;
    101         Object[] newArguments = new Object[size + 1];
    102         System.arraycopy(arguments, 0, newArguments, 1, size);
    103         newArguments[0] = null;
    104         return metaMethod.invoke(null, newArguments);
    105     }
    106 }