/FileExtraction/Java_unseen/dlitz_resin/modules/resin/src/com/caucho/bam/packet/Query.java
/*
 * Copyright (c) 1998-2011 Caucho Technology -- all rights reserved
 *
 * This file is part of Resin(R) Open Source
 *
 * Each copy or derived work must preserve the copyright notice and this
 * notice unmodified.
 *
 * Resin Open Source is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Resin Open Source 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, or any warranty
 * of NON-INFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Resin Open Source; if not, write to the
 *
 *   Free Software Foundation, Inc.
 *   59 Temple Place, Suite 330
 *   Boston, MA 02111-1307  USA
 *
 * @author Scott Ferguson
 */

package com.caucho.bam.packet;

import java.io.Serializable;

import com.caucho.bam.BamError;
import com.caucho.bam.stream.MessageStream;

/**
 * RPC call requesting information/data.  The "id" field is used
 * to match the query with the response.  The target must either respond
 * with a QueryResult or QueryError.
 */
public class Query extends Packet {
  private final long _id;
  
  private final Serializable _value;

  /**
   * A query to a target from a given source
   *
   * @param id the query id
   * @param to the target address
   * @param from the source address
   * @param value the query content
   */
  public Query(long id, String to, String from, Serializable value)
  {
    super(to, from);

    _id = id;
    _value = value;
  }

  /**
   * Returns the id
   */
  public long getId()
  {
    return _id;
  }

  /**
   * Returns the query value
   */
  public Serializable getValue()
  {
    return _value;
  }

  /**
   * SPI method to dispatch the packet to the proper handler
   */
  @Override
  public void dispatch(MessageStream handler, MessageStream toSource)
  {
    try {
      handler.query(getId(), getTo(), getFrom(), getValue());
    } catch (RuntimeException e) {
      toSource.queryError(getId(), getFrom(), getTo(), getValue(),
                          BamError.create(e));
      
      throw e;
    } catch (Error e) {
      toSource.queryError(getId(), getFrom(), getTo(), getValue(),
                          BamError.create(e));
      
      throw e;
    }
  }

  /**
   * SPI method to dispatch the packet to the proper handler
   */
  @Override
  public void dispatchError(MessageStream handler,
                            MessageStream toSource,
                            BamError error)
  {
    toSource.queryError(getId(), getFrom(), getTo(), getValue(), error);
  }

  @Override
  public String toString()
  {
    StringBuilder sb = new StringBuilder();

    sb.append(getClass().getSimpleName());
    sb.append("[");

    sb.append("id=");
    sb.append(_id);
    
    if (getTo() != null) {
      sb.append(",to=");
      sb.append(getTo());
    }
    
    if (getFrom() != null) {
      sb.append(",from=");
      sb.append(getFrom());
    }

    if (_value != null) {
      sb.append("," + _value.getClass().getName());
    }
    
    sb.append("]");
    
    return sb.toString();
  }
}
