hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/web/resources/EnumParam.java

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.hadoop.hdfs.web.resources;

import java.util.Arrays;
import org.apache.hadoop.util.StringUtils;

abstract class EnumParam<E extends Enum<E>>
    extends Param<E, EnumParam.Domain<E>> {
  EnumParam(final Domain<E> domain, final E value) {
    super(domain, value);
  }

  /** The domain of the parameter. */
  static final class Domain<E extends Enum<E>> extends Param.Domain<E> {
    private final Class<E> enumClass;

    Domain(String name, final Class<E> enumClass) {
      super(name);
      this.enumClass = enumClass;
    }

    @Override
    public final String getDomain() {
      return Arrays.asList(enumClass.getEnumConstants()).toString();
    }

    @Override
    final E parse(final String str) {
      return Enum.valueOf(enumClass, StringUtils.toUpperCase(str));
    }
  }
}