1 /*
2 * Copyright (c) 2016, 2019, 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 /**
27 * This application is meant to be run to create a classlist file representing
28 * common use.
29 *
30 * The classlist is produced by adding -XX:DumpLoadedClassList=classlist
31 */
32 package build.tools.classlist;
33
34 import java.net.InetAddress;
35 import java.nio.file.FileSystems;
36 import java.time.LocalDateTime;
37 import java.time.ZoneId;
38 import java.time.format.DateTimeFormatter;
39 import java.util.stream.Stream;
40 import java.util.logging.*;
41 import java.util.Arrays;
42 import java.util.Date;
43 import java.util.List;
44 import java.util.Locale;
45 import java.text.DateFormat;
46
47 import static java.util.stream.Collectors.*;
48
49 /**
50 * This class is used to generate a classlist during build. Intent
51 * is to touch a reasonable amount of JDK classes that are commonly
52 * loaded and used early.
53 */
54 public class HelloClasslist {
55
56 private static final Logger LOGGER = Logger.getLogger("Hello");
57
58 public static void main(String ... args) {
59
60 FileSystems.getDefault();
61
62 List<String> strings = Arrays.asList("Hello", "World!", "From: ",
63 InetAddress.getLoopbackAddress().toString());
64
65 String helloWorld = strings.parallelStream()
66 .map(s -> s.toLowerCase(Locale.ROOT))
67 .collect(joining(","));
68
69 Stream.of(helloWorld.split(","))
70 .forEach(System.out::println);
71
72 // Common concatenation patterns
73 String SS = String.valueOf(args.length) + String.valueOf(args.length);
74 String CS = "string" + String.valueOf(args.length);
75 String SC = String.valueOf(args.length) + "string";
76 String SCS = String.valueOf(args.length) + "string" + String.valueOf(args.length);
77 String CSS = "string" + String.valueOf(args.length) + String.valueOf(args.length);
78 String CSC = "string" + String.valueOf(args.length) + "string";
79 String SSC = String.valueOf(args.length) + String.valueOf(args.length) + "string";
80 String CSCS = "string" + String.valueOf(args.length) + "string" + String.valueOf(args.length);
81 String SCSC = String.valueOf(args.length) + "string" + String.valueOf(args.length) + "string";
82 String CSCSC = "string" + String.valueOf(args.length) + "string" + String.valueOf(args.length) + "string";
83 String SCSCS = String.valueOf(args.length) + "string" + String.valueOf(args.length) + "string" + String.valueOf(args.length);
84 String CI = "string" + args.length;
85 String IC = args.length + "string";
86 String CIC = "string" + args.length + "string";
87 String CICI = "string" + args.length + "string" + args.length;
88 String CJ = "string" + System.currentTimeMillis();
89 String JC = System.currentTimeMillis() + "string";
90 String CJC = "string" + System.currentTimeMillis() + "string";
91 String CJCJ = "string" + System.currentTimeMillis() + "string" + System.currentTimeMillis();
92 String CJCJC = "string" + System.currentTimeMillis() + "string" + System.currentTimeMillis() + "string";
93
94 String newDate = DateTimeFormatter.ISO_LOCAL_DATE_TIME.format(
95 LocalDateTime.now(ZoneId.of("GMT")));
96
97 String oldDate = String.format("%s%n",
98 DateFormat.getDateInstance(DateFormat.DEFAULT, Locale.ROOT)
99 .format(new Date()));
100
101 LOGGER.log(Level.INFO, "New Date: " + newDate + " - old: " + oldDate);
102 }
103
104 }