1 /*
 2  * Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
 3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 4  *
 5  * This code is free software; you can redistribute it and/or modify it
 6  * under the terms of the GNU General Public License version 2 only, as
 7  * published by the Free Software Foundation.
 8  *
 9  * This code is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * version 2 for more details (a copy is included in the LICENSE file that
13  * accompanied this code).
14  *
15  * You should have received a copy of the GNU General Public License version
16  * 2 along with this work; if not, write to the Free Software Foundation,
17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18  *
19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20  * or visit www.oracle.com if you need additional information or have any
21  * questions.
22  */
23 package org.openjdk.bench.java.nio;
24 
25 import java.nio.CharBuffer;
26 import java.util.concurrent.TimeUnit;
27 
28 import org.openjdk.jmh.annotations.Benchmark;
29 import org.openjdk.jmh.annotations.Fork;
30 import org.openjdk.jmh.annotations.Measurement;
31 import org.openjdk.jmh.annotations.Scope;
32 import org.openjdk.jmh.annotations.State;
33 import org.openjdk.jmh.annotations.Warmup;
34 
35 /**
36  * Benchmark for bulk get methods of a {@code CharBuffer} created from a
37  * {@code CharSequence}.
38  */
39 
40 @Warmup(iterations = 5, time = 500, timeUnit = TimeUnit.MILLISECONDS)
41 @Measurement(iterations = 10, time = 500, timeUnit = TimeUnit.MILLISECONDS)
42 @State(Scope.Benchmark)
43 @Fork(1)
44 public class StringCharBufferBulkTransfer {
45     private static final int LENGTH = 16384;
46 
47     char[] buf = new char[LENGTH];
48     @SuppressWarnings("initialization")
49     CharBuffer cb = CharBuffer.wrap(new String(buf));
50     char[] dst = new char[LENGTH];
51     CharBuffer cbw = CharBuffer.allocate(LENGTH);
52 
53     @Benchmark
54     public void absoluteBulkGet() {
55         cb.get(0, dst, 0, dst.length);
56     }
57 
58     @Benchmark
59     public void relativeBulkGet() {
60         cb.get(dst, 0, dst.length);
61         cb.position(0);
62     }
63 
64     @Benchmark
65     public void getChars() {
66         cb.getChars(0, LENGTH, dst, 0);
67     }
68 
69     @Benchmark
70     public void absoluteBulkPut() {
71         cbw.put(0, cb, 0, dst.length);
72     }
73 }