# FunctionKey.java

    /*
    ** Module   : FunctionKey.java
    ** Abstract : Function descriptor which can be used as a hash table key
    **
    ** Copyright (c) 2004-2020, Golden Code Development Corporation.
    **
    ** -#- -I- --Date-- --JPRM-- ----------------------------Description-----------------------------
    ** 001 ECF 20080312  @37493  Created initial version. Function descriptor which can be used as a
    **                           hash table key.
    ** 002 ECF 20080508  @38486  Use Database object rather than database name String. This allows
    **                           differentiation of the same function across multiple databases with
    **                           the same name.
    ** 003 ECF 20150223          Lower case function name on construction to ensure case-insensitive
    **                           look-ups.
    ** 004 OM  20151130          Removed NPE in toString() when database was not set.
    ** 005 ECF 20200906          New ORM implementation.
    */

    /*
    ** This program is free software: you can redistribute it and/or modify
    ** it under the terms of the GNU Affero General Public License as
    ** published by the Free Software Foundation, either version 3 of the
    ** License, or (at your option) any later version.
    **
    ** This program 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 Affero General Public License for more details.
    **
    ** You may find a copy of the GNU Affero GPL version 3 at the following
    ** location: https://www.gnu.org/licenses/agpl-3.0.en.html
    **
    ** Additional terms under GNU Affero GPL version 3 section 7:
    **
    **   Under Section 7 of the GNU Affero GPL version 3, the following additional
    **   terms apply to the works covered under the License.  These additional terms
    **   are non-permissive additional terms allowed under Section 7 of the GNU
    **   Affero GPL version 3 and may not be removed by you.
    **
    **   0. Attribution Requirement.
    **
    **     You must preserve all legal notices or author attributions in the covered
    **     work or Appropriate Legal Notices displayed by works containing the covered
    **     work.  You may not remove from the covered work any author or developer
    **     credit already included within the covered work.
    **
    **   1. No License To Use Trademarks.
    **
    **     This license does not grant any license or rights to use the trademarks
    **     Golden Code, FWD, any Golden Code or FWD logo, or any other trademarks
    **     of Golden Code Development Corporation. You are not authorized to use the
    **     name Golden Code, FWD, or the names of any author or contributor, for
    **     publicity purposes without written authorization.
    **
    **   2. No Misrepresentation of Affiliation.
    **
    **     You may not represent yourself as Golden Code Development Corporation or FWD.
    **
    **     You may not represent yourself for publicity purposes as associated with
    **     Golden Code Development Corporation, FWD, or any author or contributor to
    **     the covered work, without written authorization.
    **
    **   3. No Misrepresentation of Source or Origin.
    **
    **     You may not represent the covered work as solely your work.  All modified
    **     versions of the covered work must be marked in a reasonable way to make it
    **     clear that the modified work is not originating from Golden Code Development
    **     Corporation or FWD.  All modified versions must contain the notices of
    **     attribution required in this license.
    */

    package com.goldencode.p2j.persist.hql;

    import com.goldencode.p2j.persist.*;

    /**
     * Descriptor of a user-defined function, suitable for use as a key in a hash table.
     */
    public final class FunctionKey
    {
       /** Database name */
       private final Database database;

       /** Function name */
       private final String function;

       /** Function parameter signature as HQL types */
       private final FqlType[] signature;

       /**
        * Constructor.
        *
        * @param   function
        *          Function name.
        * @param   signature
        *          Function parameter signature as HQL types.
        */
       public FunctionKey(String function, FqlType[] signature)
       {
          this(null, function, signature);
       }

       /**
        * Constructor.
        *
        * @param   database
        *          Database.
        * @param   function
        *          Function name.
        * @param   signature
        *          Function parameter signature as HQL types.
        */
       public FunctionKey(Database database, String function, FqlType[] signature)
       {
          this.database = database;
          this.function = function.toLowerCase().intern();
          this.signature = signature;
       }

       /**
        * Return hash code for this object.
        *
        * @return  Hash code.
        *
        * @see java.lang.Object#hashCode()
        */
       public int hashCode()
       {
          int result = 17;

          result = 37 * result + (database != null ? database.hashCode() : 0);
          result = 37 * result + function.hashCode();
          for (FqlType type : signature)
          {
             result = 37 * result + type.hashCode();
          }

          return result;
       }

       /**
        * Test this object for equality with the given object, which is assumed to
        * be an instance of this class.
        *
        * @return  <code>true</code> if objects are equal, else <code>false</code>.
        *
        * @see java.lang.Object#equals(java.lang.Object)
        */
       public boolean equals(Object o)
       {
          if (!(o instanceof FunctionKey))
          {
             return false;
          }

          FunctionKey that = (FunctionKey) o;

          boolean bothNull = false;

          if (database == null || that.database == null)
          {
             bothNull = (database == that.database);
             if (!bothNull)
             {
                return false;
             }
          }

          if (!bothNull && !database.equals(that.database))
          {
             return false;
          }

          if (!function.equals(that.function))
          {
             return false;
          }

          int len1 = signature.length;
          int len2 = that.signature.length;

          if (len1 != len2)
          {
             return false;
          }

          for (int i = 0; i < len1; i++)
          {
             if (!signature[i].equals(that.signature[i]))
             {
                return false;
             }
          }

          return true;
       }

       /**
        * Get a string representation of this object's state.
        *
        * @return  String representation of this object.
        *
        * @see java.lang.Object#toString()
        */
       public String toString()
       {
          StringBuilder buf = new StringBuilder(database == null ? "" : database.toString());
          buf.append("::");
          buf.append(function);
          buf.append("(");
          for (int i = 0; i < signature.length; i++)
          {
             if (i > 0)
             {
                buf.append(", ");
             }

             buf.append(signature[i]);
          }
          buf.append(")");

          return buf.toString();
       }
    }