1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.apache.maven.index.reader;
20
21 import java.io.IOException;
22 import java.io.OutputStream;
23
24 /**
25 * Maven Index writable {@link ResourceHandler}, is capable of saving resources too. Needed only if incremental index
26 * updates are wanted, to store the index state locally, and be able to calculate incremental diffs on next {@link
27 * IndexReader} invocation. Is used by single thread only.
28 *
29 * @see ResourceHandler
30 * @since 5.1.2
31 */
32 public interface WritableResourceHandler extends ResourceHandler {
33 /**
34 * Resource that is writable.
35 */
36 interface WritableResource extends Resource {
37 /**
38 * Returns the {@link OutputStream} stream of the resource, if exists, it will replace the existing content, or
39 * if not exists, the resource will be created. The stream should be closed by caller, otherwise resource leaks
40 * might be introduced. How and when content is written is left to implementation, but it is guaranteed that
41 * this method is called only once, and will be followed by {@link #close()} on the resource itself.
42 * Implementation does not have to be "read consistent", in a way to worry what subsequent {@link #read()}
43 * method will return, as mixed calls will not happen on same instance of resource.
44 */
45 OutputStream write() throws IOException;
46 }
47
48 /**
49 * Returns the {@link WritableResource} with {@code name}. Returned locator should be handled as
50 * resource.
51 *
52 * @param name Resource name, guaranteed to be non-{@code null} and is FS and URL safe string.
53 */
54 WritableResource locate(String name) throws IOException;
55 }