1 /*
2 * ====================================================================
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 * ====================================================================
20 *
21 * This software consists of voluntary contributions made by many
22 * individuals on behalf of the Apache Software Foundation. For more
23 * information on the Apache Software Foundation, please see
24 * <http://www.apache.org/>.
25 *
26 */
27
28 package org.apache.hc.core5.http.io;
29
30 import java.io.IOException;
31
32 import org.apache.hc.core5.http.HttpConnection;
33 import org.apache.hc.core5.util.Timeout;
34
35 /**
36 * Abstract blocking HTTP connection interface.
37 *
38 * @since 5.0
39 */
40 public interface BHttpConnection extends HttpConnection {
41
42 /**
43 * Checks if input data is available from the connection. May wait for
44 * the specified time until some data becomes available. Note that some
45 * implementations may completely ignore the timeout parameter.
46 *
47 * @param timeout the maximum time to wait for data
48 * @return true if data is available; false if there was no data available
49 * even after waiting for {@code timeout}.
50 * @throws IOException if an error happens on the connection
51 */
52 boolean isDataAvailable(Timeout timeout) throws IOException;
53
54 /**
55 * Checks whether this connection has gone down.
56 * Network connections may get closed during some time of inactivity
57 * for several reasons. The next time a read is attempted on such a
58 * connection it will throw an IOException.
59 * This method tries to alleviate this inconvenience by trying to
60 * find out if a connection is still usable. Implementations may do
61 * that by attempting a read with a very small timeout. Thus this
62 * method may block for a small amount of time before returning a result.
63 * It is therefore an <i>expensive</i> operation.
64 *
65 * @return {@code true} if attempts to use this connection are
66 * likely to succeed, or {@code false} if they are likely
67 * to fail and this connection should be closed
68 */
69 boolean isStale() throws IOException;
70
71 /**
72 * Writes out all pending buffered data over the open connection.
73 *
74 * @throws java.io.IOException in case of an I/O error
75 */
76 void flush() throws IOException;
77
78 }