/*
 * 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.commons.configuration2.io;

import java.io.IOException;
import java.io.Reader;
import java.io.Writer;

import org.apache.commons.configuration2.ex.ConfigurationException;


Definition of an interface to be implemented by objects which know how to
read and write themselves from or to a character stream.

 This interface is implemented by special implementations of the Configuration interface which are associated with a file. It demands only basic methods for doing I/O based on character stream objects. Based on these methods it is possible to implement other methods which operate on files, file names, URLs, etc. 

Note that the methods defined by this interface are not intended to
be called directly by client code! Rather, they are used internally when doing I/O operations with a FileHandler. A FileHandler supports additional functionality (e.g. it evaluates some additional interfaces the FileBased object may implement); this functionality is not available on a direct method invocation, so this may lead to unpredictable results. 
/**
 * <p>
 * Definition of an interface to be implemented by objects which know how to
 * read and write themselves from or to a character stream.
 * </p>
 * <p>
 * This interface is implemented by special implementations of the
 * {@code Configuration} interface which are associated with a file. It demands
 * only basic methods for doing I/O based on character stream objects. Based on
 * these methods it is possible to implement other methods which operate on
 * files, file names, URLs, etc.
 * </p>
 * <p>
 * <strong>Note that the methods defined by this interface are not intended to
 * be called directly by client code!</strong> Rather, they are used internally
 * when doing I/O operations with a {@link FileHandler}. A {@code FileHandler}
 * supports additional functionality (e.g. it evaluates some additional
 * interfaces the {@code FileBased} object may implement); this functionality
 * is not available on a direct method invocation, so this may lead to
 * unpredictable results.
 * </p>
 *
 */
public interface FileBased
{
    
Reads the content of this object from the given reader.
Client code should not call this method directly, but use a FileHandler for reading data.
Params:
in – the reader
Throws:
IOException – if an I/O error occurs
ConfigurationException – if a non-I/O related problem occurs, e.g.
        the data read does not have the expected format/**
     * Reads the content of this object from the given reader.
     * <strong>Client code should not call this method directly, but use a
     * {@code FileHandler} for reading data.</strong>
     *
     * @param in the reader
     * @throws IOException if an I/O error occurs
     * @throws ConfigurationException if a non-I/O related problem occurs, e.g.
     *         the data read does not have the expected format
     */
    void read(Reader in) throws ConfigurationException, IOException;

    
Writes the content of this object to the given writer.
Client code should not call this method directly, but use a FileHandler for writing data.
Params:
out – the writer
Throws:
IOException – if an I/O error occurs
ConfigurationException – if a non-I/O related problem occurs, e.g.
        the data read does not have the expected format/**
     * Writes the content of this object to the given writer.
     * <strong>Client code should not call this method directly, but use a
     * {@code FileHandler} for writing data.</strong>
     *
     * @param out the writer
     * @throws IOException if an I/O error occurs
     * @throws ConfigurationException if a non-I/O related problem occurs, e.g.
     *         the data read does not have the expected format
     */
    void write(Writer out) throws ConfigurationException, IOException;
}