/*
    * Copyright 2009 the original author or authors.
    * 
    * Licensed under the Apache License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    *     http://www.apache.org/licenses/LICENSE-2.0
    *     
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.openehealth.ipf.commons.ihe.xds.core.requests.query;
  
  import lombok.EqualsAndHashCode;
  import lombok.Getter;
  import lombok.ToString;
  
  import static org.apache.commons.lang3.Validate.notNull;
  
  import javax.xml.bind.annotation.*;
  import java.io.Serializable;
  
  /**
   * Base class for all query requests.
   * @author Jens Riemschneider
   */
  @XmlAccessorType(XmlAccessType.FIELD)
  @XmlType(name = "Query")
  @EqualsAndHashCode(doNotUseGetters = true)
  @ToString(doNotUseGetters = true)
  public abstract class Query implements Serializable {
      private static final long serialVersionUID = 7597105342752455732L;
  
      @XmlAttribute
      @Getter private QueryType type;
  
      /**
       * For JAXB serialization only.
       */
      public Query() {
      }
  
      /**
       * Constructs the query.
       * @param type
       *          the type of the query.
       */
      protected Query(QueryType type) {
          notNull(type, "type cannot be null");
          this.type = type;
      }
  
      /**
       * Visitor interface used for this class to implement the visitor pattern.
       */
      public interface Visitor {
          void visit(FindDocumentsQuery query);
          void visit(FindDocumentsForMultiplePatientsQuery query);
          void visit(FindFoldersQuery query);
          void visit(FindFoldersForMultiplePatientsQuery query);
          void visit(GetSubmissionSetsQuery query);
          void visit(GetSubmissionSetAndContentsQuery query);
          void visit(GetRelatedDocumentsQuery query);
          void visit(GetFoldersQuery query);
          void visit(GetFoldersForDocumentQuery query);
          void visit(GetFolderAndContentsQuery query);
          void visit(GetDocumentsQuery query);
          void visit(GetDocumentsAndAssociationsQuery query);
          void visit(GetAssociationsQuery query);
          void visit(GetAllQuery query);
          void visit(FindSubmissionSetsQuery query);
          void visit(FetchQuery query);
          void visit(FindDocumentsByReferenceIdQuery query);
      }
      
      /**
       * Accept a visitor to process an instance of this class.
       * @param visitor
       *          the visitor implementation.
       */
      public abstract void accept(Visitor visitor);
  }