1 /*
2 * Copyright (c) 2016, 2020, 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 package jdk.tools.jlink.internal.plugins;
26
27 import java.io.BufferedReader;
28 import java.io.File;
29 import java.io.IOException;
30 import java.io.InputStream;
31 import java.io.InputStreamReader;
32 import java.nio.file.Files;
33 import java.util.EnumSet;
34 import java.util.List;
35 import java.util.Map;
36 import java.util.Set;
37
38 import jdk.internal.access.JavaLangInvokeAccess;
39 import jdk.internal.access.SharedSecrets;
40 import jdk.tools.jlink.plugin.Plugin;
41 import jdk.tools.jlink.plugin.PluginException;
42 import jdk.tools.jlink.plugin.ResourcePool;
43 import jdk.tools.jlink.plugin.ResourcePoolBuilder;
44 import jdk.tools.jlink.plugin.ResourcePoolEntry;
45
46 /**
47 * Plugin to generate java.lang.invoke classes.
48 *
49 * The plugin reads in a file generated by running any application with
50 * {@code -Djava.lang.invoke.MethodHandle.TRACE_RESOLVE=true}. This is done
51 * automatically during build, see make/GenerateLinkOptData.gmk. See
52 * build/tools/classlist/HelloClasslist.java for the training application.
53 *
54 * HelloClasslist tries to reflect common use of java.lang.invoke during early
55 * startup and warmup in various applications. To ensure a good default
56 * trade-off between static footprint and startup the application should be
57 * relatively conservative.
58 *
59 * When using jlink to build a custom application runtime, generating a trace
60 * file using {@code -Djava.lang.invoke.MethodHandle.TRACE_RESOLVE=true} and
61 * feeding that into jlink using {@code --generate-jli-classes=@trace_file} can
62 * help improve startup time.
63 */
64 public final class GenerateJLIClassesPlugin implements Plugin {
65
66 private static final String NAME = "generate-jli-classes";
67
68 private static final String DESCRIPTION = PluginsResourceBundle.getDescription(NAME);
69
70 private static final String DEFAULT_TRACE_FILE = "default_jli_trace.txt";
71
72 private static final JavaLangInvokeAccess JLIA = SharedSecrets.getJavaLangInvokeAccess();
73
74 String mainArgument;
75 String[] lines = null;
76
77 public GenerateJLIClassesPlugin() {
78 }
79
80 @Override
81 public String getName() {
82 return NAME;
83 }
84
85 @Override
86 public String getDescription() {
87 return DESCRIPTION;
88 }
89
90 @Override
91 public Set<State> getState() {
92 return EnumSet.of(State.AUTO_ENABLED, State.FUNCTIONAL);
93 }
94
95 @Override
96 public boolean hasArguments() {
97 return true;
98 }
99
100 @Override
101 public String getArgumentsDescription() {
102 return PluginsResourceBundle.getArgument(NAME);
103 }
104
105 @Override
106 public void configure(Map<String, String> config) {
107 mainArgument = config.get(NAME);
108 }
109
110 // Repeat def, we do not have access right to InvokerBytecodeGeneratorHelper
111 // Must be exact same!
112 private static final String DIRECT_METHOD_HOLDER_ENTRY =
113 "/java.base/java/lang/invoke/DirectMethodHandle$Holder.class";
114 private static final String DELEGATING_METHOD_HOLDER_ENTRY =
115 "/java.base/java/lang/invoke/DelegatingMethodHandle$Holder.class";
116 private static final String INVOKERS_HOLDER_ENTRY =
117 "/java.base/java/lang/invoke/Invokers$Holder.class";
118 private static final String BASIC_FORMS_HOLDER_ENTRY =
119 "/java.base/java/lang/invoke/LambdaForm$Holder.class";
120
121 @Override
122 public ResourcePool transform(ResourcePool in, ResourcePoolBuilder out) {
123 initialize(in);
124 // Copy all but DMH_ENTRY to out
125 in.transformAndCopy(entry -> {
126 // filter out placeholder entries
127 String path = entry.path();
128 if (path.equals(DIRECT_METHOD_HOLDER_ENTRY) ||
129 path.equals(DELEGATING_METHOD_HOLDER_ENTRY) ||
130 path.equals(INVOKERS_HOLDER_ENTRY) ||
131 path.equals(BASIC_FORMS_HOLDER_ENTRY)) {
132 return null;
133 } else {
134 return entry;
135 }
136 }, out);
137
138 // Generate LambdaForm Holder classes
139 generateHolderClasses(out);
140 // clear input.
141 lines = null;
142 return out.build();
143 }
144
145 private void generateHolderClasses(ResourcePoolBuilder out) {
146 try {
147 Map<String, byte[]> result = JLIA.generateMethodHandleHolderClasses(lines);
148 if (result != null) {
149 result.forEach ((k,v) -> {
150 ResourcePoolEntry ndata = ResourcePoolEntry.create(k, v);
151 out.add(ndata);
152 });
153 }
154 } catch (Exception ex) {
155 throw new PluginException(ex);
156 }
157 }
158
159 public void initialize(ResourcePool in) {
160 // Load configuration from the contents in the supplied input file
161 // - if none was supplied we look for the default file
162 if (mainArgument == null || !mainArgument.startsWith("@")) {
163 try (InputStream traceFile =
164 this.getClass().getResourceAsStream(DEFAULT_TRACE_FILE)) {
165 if (traceFile != null) {
166 lines = new BufferedReader(
167 new InputStreamReader(traceFile)).lines().toArray(String[]::new);
168 }
169 } catch (Exception e) {
170 throw new PluginException("Couldn't read " + DEFAULT_TRACE_FILE, e);
171 }
172 } else {
173 File file = new File(mainArgument.substring(1));
174 try {
175 if (file.exists()) {
176 lines = Files.readAllLines(file.toPath()).toArray(new String[0]);
177 }
178 } catch (Exception e) {
179 throw new PluginException("Couldn't read " + file.getName(), e);
180 }
181 }
182 }
183 }