1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.configuration2.io;
18
19 import java.io.IOException;
20 import java.io.Reader;
21 import java.io.Writer;
22
23 import org.apache.commons.configuration2.ex.ConfigurationException;
24
25 /**
26 * <p>
27 * Definition of an interface to be implemented by objects which know how to read and write themselves from or to a
28 * character stream.
29 * </p>
30 * <p>
31 * This interface is implemented by special implementations of the {@code Configuration} interface which are associated
32 * with a file. It demands only basic methods for doing I/O based on character stream objects. Based on these methods it
33 * is possible to implement other methods which operate on files, file names, URLs, etc.
34 * </p>
35 * <p>
36 * <strong>Note that the methods defined by this interface are not intended to be called directly by client
37 * code!</strong> Rather, they are used internally when doing I/O operations with a {@link FileHandler}. A
38 * {@code FileHandler} supports additional functionality (e.g. it evaluates some additional interfaces the
39 * {@code FileBased} object may implement); this functionality is not available on a direct method invocation, so this
40 * may lead to unpredictable results.
41 * </p>
42 */
43 public interface FileBased {
44 /**
45 * Reads the content of this object from the given reader. <strong>Client code should not call this method directly, but
46 * use a {@code FileHandler} for reading data.</strong>
47 *
48 * @param in the reader
49 * @throws IOException if an I/O error occurs.
50 * @throws ConfigurationException if a non-I/O related problem occurs, e.g. the data read does not have the expected
51 * format
52 */
53 void read(Reader in) throws ConfigurationException, IOException;
54
55 /**
56 * Writes the content of this object to the given writer. <strong>Client code should not call this method directly, but
57 * use a {@code FileHandler} for writing data.</strong>
58 *
59 * @param out the writer
60 * @throws IOException if an I/O error occurs.
61 * @throws ConfigurationException if a non-I/O related problem occurs, e.g. the data read does not have the expected
62 * format
63 */
64 void write(Writer out) throws ConfigurationException, IOException;
65 }