1 /*
2 * Copyright (C) 2007 The Guava Authors
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
5 * in compliance with the License. You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software distributed under the License
10 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
11 * or implied. See the License for the specific language governing permissions and limitations under
12 * the License.
13 */
14
15 package com.google.common.io;
16
17 import com.google.common.annotations.Beta;
18 import com.google.common.annotations.GwtIncompatible;
19 import java.io.Flushable;
20 import java.io.IOException;
21 import java.util.logging.Level;
22 import java.util.logging.Logger;
23
24 /**
25 * Utility methods for working with {@link Flushable} objects.
26 *
27 * @author Michael Lancaster
28 * @since 1.0
29 */
30 @Beta
31 @GwtIncompatible
32 @ElementTypesAreNonnullByDefault
33 public final class Flushables {
34 private static final Logger logger = Logger.getLogger(Flushables.class.getName());
35
36 private Flushables() {}
37
38 /**
39 * Flush a {@link Flushable}, with control over whether an {@code IOException} may be thrown.
40 *
41 * <p>If {@code swallowIOException} is true, then we don't rethrow {@code IOException}, but merely
42 * log it.
43 *
44 * @param flushable the {@code Flushable} object to be flushed.
45 * @param swallowIOException if true, don't propagate IO exceptions thrown by the {@code flush}
46 * method
47 * @throws IOException if {@code swallowIOException} is false and {@link Flushable#flush} throws
48 * an {@code IOException}.
49 * @see Closeables#close
50 */
51 public static void flush(Flushable flushable, boolean swallowIOException) throws IOException {
52 try {
53 flushable.flush();
54 } catch (IOException e) {
55 if (swallowIOException) {
56 logger.log(Level.WARNING, "IOException thrown while flushing Flushable.", e);
57 } else {
58 throw e;
59 }
60 }
61 }
62
63 /**
64 * Equivalent to calling {@code flush(flushable, true)}, but with no {@code IOException} in the
65 * signature.
66 *
67 * @param flushable the {@code Flushable} object to be flushed.
68 */
69 public static void flushQuietly(Flushable flushable) {
70 try {
71 flush(flushable, true);
72 } catch (IOException e) {
73 logger.log(Level.SEVERE, "IOException should not have been thrown.", e);
74 }
75 }
76 }