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/*
 * ==========================================================================
 * Copyright (C) 2019-2022 HCL America, Inc. ( http://www.hcl.com/ )
 *                            All rights reserved.
 * ==========================================================================
 * 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 .
 *
 * 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 com.hcl.domino.data;

import java.util.List;

/**
 * Generic value converter interface
 *
 * @author Karsten Lehmann
 * @param  type of object containing the data
 */
public interface ValueConverter {

  /**
   * Determines the relative priority of this converter compared to other
   * converters
   * of the same type.
   * 
   * The default value is {@code 0} and higher values take precedence.
   * 
   *
   * @return the relative priority value of this converter
   */
  default int getPriority() {
    return 0;
  }

  /**
   * Implement this method to return the converted value type.

   * Will only be invoked if {@link #supportsRead(Class)} returns
   * true.
   *
   * @param           value type
   * @param obj          object
   * @param itemName     item to read
   * @param valueType    requested return value type
   * @param defaultValue default value to return if object property is not set
   * @return return value or null
   */
   T getValue(OBJ obj, String itemName, Class valueType, T defaultValue);

  /**
   * Implement this method to return a list of the converted value type.

   * Will only be invoked if {@link #supportsRead(Class)} returns
   * true.
   *
   * @param           value type
   * @param obj          object
   * @param itemName     item to read
   * @param valueType    requested return value type
   * @param defaultValue default value to return if object property is not set
   * @return return value or null
   */
   List getValueAsList(OBJ obj, String itemName, Class valueType, List defaultValue);

  /**
   * Implement this method to write a value to the object
   *
   * @param       value type
   * @param obj      object
   * @param itemName name of item to write
   * @param newValue new value
   */
   void setValue(OBJ obj, String itemName, T newValue);

  /**
   * Return true here for all value types that
   * the implementation class supports to read object
   * data.
   *
   * @param valueType requested return value type
   * @return true if supported type
   */
  boolean supportsRead(Class valueType);

  /**
   * Return true here for all value types that
   * the implementation class supports to write object
   * data.
   *
   * @param valueType requested return value type
   * @param value     the requested value to write (may be null)
   * @return true if supported type
   */
  boolean supportsWrite(Class valueType, Object value);
}