ThriftDtoConverter.java

/*
 * Copyright 2014 CyberVision, Inc.
 *
 * 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.kaaproject.kaa.server.common.thrift.util;

import org.kaaproject.kaa.common.dto.DtoByteMarshaller;
import org.kaaproject.kaa.common.dto.HasId;
import org.kaaproject.kaa.server.common.thrift.gen.shared.DataStruct;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

/**
 * The Class ThriftDtoConverter.<br>
 * Used to convert Data Transfer Objects (DTOs) to Thrift DataStruct structure
 * and vice versa
 */
public class ThriftDtoConverter {

  private ThriftDtoConverter() {
  }

  /**
   * Convert DTO to thrift DataStruct.
   *
   * @param <T> the DTO generic type
   * @param dto the DTO
   * @return the thrift DataStruct
   */
  public static <T extends HasId> DataStruct toDataStruct(T dto) {
    DataStruct dataStruct = new DataStruct();
    if (dto != null) {
      dataStruct.setKey(dto.getId());
      dataStruct.setData(DtoByteMarshaller.toBytes(dto));
    }
    return dataStruct;
  }

  /**
   * Convert DTO to thrift DataStruct.
   *
   * @param <T> the DTO generic type
   * @param dto the DTO
   * @return the thrift DataStruct
   */
  public static <T> DataStruct toGenericDataStruct(T dto) {
    DataStruct dataStruct = new DataStruct();
    if (dto != null) {
      dataStruct.setData(DtoByteMarshaller.toBytes(dto));
    }
    return dataStruct;
  }

  /**
   * Convert DTOs list to thrift DataStructs list.
   *
   * @param <T>     the DTO generic type
   * @param dtoList the DTOs list
   * @return the thrift DataStructs list
   */
  public static <T extends HasId> List<DataStruct> toDataStructList(
      Collection<T> dtoList) {
    List<DataStruct> dataStructList = new ArrayList<DataStruct>(
        dtoList.size());
    for (T dto : dtoList) {
      dataStructList.add(toDataStruct(dto));
    }
    return dataStructList;
  }

  /**
   * Convert DTOs list to thrift DataStructs list.
   *
   * @param <T>     the DTO generic type
   * @param dtoList the DTOs list
   * @return the thrift DataStructs list
   */
  public static <T> List<DataStruct> toGenericDataStructList(
      Collection<T> dtoList) {
    List<DataStruct> dataStructList = new ArrayList<DataStruct>(
        dtoList.size());
    for (T dto : dtoList) {
      dataStructList.add(toGenericDataStruct(dto));
    }
    return dataStructList;
  }

  /**
   * Convert thrift DataStruct to DTO.
   *
   * @param <T>        the DTO generic type
   * @param dataStruct the thrift DataStruct
   * @return the DTO
   */
  public static <T extends HasId> T toDto(DataStruct dataStruct) {
    T dto = null;
    if (dataStruct != null && dataStruct.getData() != null) {
      dto = DtoByteMarshaller.fromBytes(dataStruct.getData());
    }
    return dto;
  }

  /**
   * Convert thrift DataStruct to DTO.
   *
   * @param <T>        the DTO generic type
   * @param dataStruct the thrift DataStruct
   * @return the DTO
   */
  public static <T> T toGenericDto(DataStruct dataStruct) {
    T dto = null;
    if (dataStruct != null && dataStruct.getData() != null) {
      dto = DtoByteMarshaller.fromBytes(dataStruct.getData());
    }
    return dto;
  }

  /**
   * Convert thrift DataStructs list to DTOs list.
   *
   * @param <T>            the DTO generic type
   * @param dataStructList the thrift DataStructs list
   * @return the DTOs list
   */
  public static <T extends HasId> List<T> toDtoList(
      Collection<DataStruct> dataStructList) {
    List<T> dtoList = new ArrayList<T>(dataStructList.size());
    for (DataStruct dataStruct : dataStructList) {
      dtoList.add(ThriftDtoConverter.<T>toDto(dataStruct));
    }
    return dtoList;
  }

  /**
   * Convert thrift DataStructs list to DTOs list.
   *
   * @param <T>            the DTO generic type
   * @param dataStructList the thrift DataStructs list
   * @return the DTOs list
   */
  public static <T> List<T> toGenericDtoList(
      Collection<DataStruct> dataStructList) {
    List<T> dtoList = new ArrayList<T>(dataStructList.size());
    for (DataStruct dataStruct : dataStructList) {
      dtoList.add(ThriftDtoConverter.<T>toGenericDto(dataStruct));
    }
    return dtoList;
  }

}