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
019package org.apache.hadoop.io;
020
021import java.io.IOException;
022
023import org.apache.hadoop.classification.InterfaceAudience;
024import org.apache.hadoop.classification.InterfaceStability;
025
026/**
027 * Stringifier interface offers two methods to convert an object 
028 * to a string representation and restore the object given its 
029 * string representation.
030 * @param <T> the class of the objects to stringify
031 */
032@InterfaceAudience.Public
033@InterfaceStability.Stable
034public interface Stringifier<T> extends java.io.Closeable {
035
036  /**
037   * Converts the object to a string representation
038   * @param obj the object to convert
039   * @return the string representation of the object
040   * @throws IOException if the object cannot be converted
041   */
042  public String toString(T obj)  throws IOException;
043  
044  /**
045   * Restores the object from its string representation.
046   * @param str the string representation of the object
047   * @return restored object
048   * @throws IOException if the object cannot be restored
049   */
050  public T fromString(String str) throws IOException;
051  
052  
053  /** 
054   * Closes this object. 
055   * @throws IOException if an I/O error occurs 
056   * */
057  @Override
058  public void close() throws IOException;
059  
060}