MapConverterSupport.java

/*
 * Copyright (c) 2009-present 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 com.planet57.gshell.util.converter.collections;

import java.beans.PropertyEditor;
import java.util.Map;

import com.planet57.gshell.util.converter.ConversionException;
import com.planet57.gshell.util.converter.ConverterSupport;
import com.planet57.gshell.util.converter.basic.StringConverter;

import javax.annotation.Nullable;

/**
 * Support for {@link Map} converters.
 *
 * @since 2.0
 */
public abstract class MapConverterSupport
    extends ConverterSupport
{
  private final PropertyEditor keyEditor;

  private final PropertyEditor valueEditor;

  public MapConverterSupport(final Class type) {
    this(type, new StringConverter(), new StringConverter());
  }

  protected MapConverterSupport(final Class type, final PropertyEditor keyEditor, final PropertyEditor valueEditor) {
    super(type);
    this.keyEditor = keyEditor;
    this.valueEditor = valueEditor;
  }

  /**
   * Treats the text value of this property as an input stream that
   * is converted into a Property bundle.
   *
   * @return a Properties object
   * @throws ConversionException An error occurred creating the Properties object.
   */
  @Override
  protected final Object convertToObject(final String text) throws Exception {
    Map map = CollectionUtil.toMap(text, keyEditor, valueEditor);
    if (map == null) {
      return null;
    }
    return createMap(map);
  }

  protected abstract Map createMap(Map map) throws Exception;

  @Override
  protected final String convertToString(final Object value) {
    Map map = (Map) value;
    return CollectionUtil.toString(map, keyEditor, valueEditor);
  }
}