com.rapiddweller.common.accessor.NullSafeAccessor Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of rd-lib-common Show documentation

'rapiddweller Common' is an open source Java library forked from Databene Commons by Volker Bergmann. It provides extensions to the Java core library by utility classes, abstract concepts and concrete implementations.

There is a newer version: 2.0.1-jdk-11

Show newest version

/*
 * Copyright (C) 2004-2015 Volker Bergmann ([email protected]).
 * 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
 * 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 com.rapiddweller.common.accessor;

import com.rapiddweller.common.Accessor;

/**
 * Accessor wrapper that returns a predefined value if getValue() is invoked with a 'null' source.
 * Created: 26.06.2005 08:22:21
 *
 * @param  the object type to access
 * @param  the type of the value to get from the object
 * @author Volker Bergmann
 */
public abstract class NullSafeAccessor extends AccessorProxy {

  private final V nullValue;

  /**
   * Instantiates a new Null safe accessor.
   *
   * @param realAccessor the real accessor
   * @param nullValue    the null value
   */
  public NullSafeAccessor(Accessor realAccessor, V nullValue) {
    super(realAccessor);
    this.nullValue = nullValue;
  }

  @Override
  public V getValue(C source) {
    return (source != null ? super.getValue(source) : nullValue);
  }
}