001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements.  See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership.  The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the
007     * "License"); you may not use this file except in compliance
008     * with the License.  You may obtain a copy of the License at
009     *
010     *     http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing, software
013     * distributed under the License is distributed on an "AS IS" BASIS,
014     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    package org.apache.hadoop.hdfs.web.resources;
019    
020    import org.apache.hadoop.conf.Configuration;
021    import org.apache.hadoop.fs.CommonConfigurationKeysPublic;
022    
023    /** Buffer size parameter. */
024    public class BufferSizeParam extends IntegerParam {
025      /** Parameter name. */
026      public static final String NAME = "buffersize";
027      /** Default parameter value. */
028      public static final String DEFAULT = NULL;
029    
030      private static final Domain DOMAIN = new Domain(NAME);
031    
032      /**
033       * Constructor.
034       * @param value the parameter value.
035       */
036      public BufferSizeParam(final Integer value) {
037        super(DOMAIN, value, 1, null);
038      }
039    
040      /**
041       * Constructor.
042       * @param str a string representation of the parameter value.
043       */
044      public BufferSizeParam(final String str) {
045        this(DOMAIN.parse(str));
046      }
047    
048      @Override
049      public String getName() {
050        return NAME;
051      }
052    
053      /** @return the value or, if it is null, return the default from conf. */
054      public int getValue(final Configuration conf) {
055        return getValue() != null? getValue()
056            : conf.getInt(
057                CommonConfigurationKeysPublic.IO_FILE_BUFFER_SIZE_KEY,
058                CommonConfigurationKeysPublic.IO_FILE_BUFFER_SIZE_DEFAULT);
059      }
060    }