1 Working on OpenJDK using NetBeans
2 This note describes how to work on the OpenJDK from NetBeans. We've
3 provided several NetBeans projects as starting points. Below we'll
4 describe how to use them, as well as how to create your own.
5
6 Getting Started
7 In addition to the source bundle for Open JDK, you'll need to download
8 and install copies of the JDK and of NetBeans. And if you want to run
9 tests on the JDK (you do want to run tests, right?), you'll need to
10 install the jtreg test harness.
11
12 In this note, when pathnames are not fully specified, they should be
13 interpreted as being relative to the directory containing this README
14 and the NetBeans projects themselves.
15
16 The JDK build process is largely make-based, and is not
17 exceptionally tolerant of pathnames with spaces in them (such as
18 "Program Files". Please be sure to install everything in a
19 directories whose paths don't have any spaces!
20
21 Downloading the JDK
22 You've probably done this a million times. Download and install it
23 from http://www.oracle.com/technetwork/java/javase/overview/index.html
24
25 Downloading the OpenJDK sources
26 Since you're reading this, d you've already downloaded the OpenJDK
27 source bundle. Later in this document we'll refer to the location
28 where you installed the Open JDK sources as *install-dir*.
29
30 Downloading a pre-built, JDK 8
31 This will be necessary to do builds of some of the projects. In
32 general, you want to download and install a pre-built JDK that
33 corresponds to the OpenJDK sources you download. Building the entire
34 OpenJDK depends on a few parts of the pre-built JDK. Get this from
35 http://download.java.net/jdk8/binaries
36
37 Note: For working on certain projects, like JMX and JConsole, you
38 may find convenient to use a pre-built version of JDK 8 (or
39 OpenJDK) rather than building your own. This will allow you
40 to build only that part of the OpenJDK sources which correspond
41 to that project.
42
43 NetBeans 7.0 or later
44 Older versions may also work but are unsupported.
45
46 jtreg
47 "jtreg" is the test harness for running OpenJDK's regression tests.
48 Get it from http://openjdk.java.net/jtreg
49
50 Ant
51 NetBeans comes with ant, but if you use a separately-installed copy
52 please make sure that it is at least version 1.8.1.
53
54 Configuring
55 Building OpenJDK is hard and complex. No, strike that. While it's not
56 exactly "easy", we've got it down to *relatively* small set of
57 properties you need to set.
58
59 The NetBeans projects provided here share a fair amount of common
60 structure. They share properties values where it makes sense. Each
61 project loads properties from these properties files, in this order
62
63 ${basedir}/nbproject/private/build.properties
64 $HOME/.openjdk/${ant.project.name}-build.properties
65 $HOME/.openjdk/build.properties
66 ${basedir}/build.properties
67
68 (${basedir} refers to the directory containing a particular NetBeans
69 project.) The first time a property defined determines value: it is
70 *not* overridden if it is read from properties files read later. The net
71 result is that by carefully choosing where to define a property, you can
72 have it for a specific project, all uses of a specific project (useful
73 if you work on multiple copies of the OpenJDK sources), all projects, or
74 only projects in a specific sandbox.
75
76 With that in mind, please set the following properties. Presuming you
77 want the same values for all your work, set them in
78 $HOME/.openjdk/build.properties.
79
80 * bootstrap.jdk
81 Set to the location where you installed JDK 7.
82
83 * jtreg.home
84 Set to the location where you installed jtreg.
85
86 * make.options
87 Some of the projects invoke "make", since they compile native code.
88 The make.options property is for passing information about what you
89 installed where to make. Change the paths to fit your particular
90 situation:
91
92 make.options=\
93 ALT_BOOTDIR=/home/me/bin/jdk1.7.0 \
94 ALT_JDK_IMPORT_PATH=/home/me/bin/jdk1.8.0 \
95 OPENJDK=true
96
97 The trailing '\' are important, so that make gets the above as a
98 single set of options.
99
100 You might want to add additional additional options: see the README
101 for the project you're using for more information. And see
102 *install-dir*/jdk/make/README-builds.html
103 to read much more about building the JDK.
104
105 Windows-specific configuration
106 First, please note that the entire JDK cannot currently be built on
107 Windows platforms. This will likely limit your ability to build
108 make-based projects. See
109 *install-dir*/jdk/make/README-builds.html
110 for full information on issues with building on the Windows platform.
111
112 That said, there are two ways to work with the Windows-required settings
113 for the Microsoft tools. Either:
114
115 * Set environment variables values in Windows
116 Doing so means accessing the System control panel in Windows, and
117 setting the environment variables there.
118
119 By doing so, you can launch NetBeans by double-clicking its icon,
120 and the environment variable values will be available.
121
122 * Set environment variable values in a shell
123 Doing so means adding the settings to an init file (e.g. .bashrc,
124 .cshrc, etc.) or a file that you source before running NetBeans. In
125 this case, you'll have to launch NetBeans from the command line in a
126 shell in which you've set the environment variables.
127
128 In either case, the end result should be that the settings are available
129 to the make-based build process when it runs from within NetBeans.
130
131 The make-based builds presumes that you're using cygwin, and expects to
132 find "make" in c:\cygwin\bin\make. If you've installed cygwin elsewhere,
133 set "make" in a properties file.
134
135 Configuring Project Properties
136 A note of caution is in order: These are NetBeans *freeform* projects.
137 If you use the NetBeans GUI to examine them, things are likely to not
138 look "right". Please don't edit them there, please instead use a text
139 editor.
140
141 Locale Requirements
142 To build the OpenJDK sources, be certain that you are using the "C"
143 locale on Unix (R) platforms, or "English (United States)" locale on
144 Windows.
145
146 Platforms and architectures, oh my!
147 The Open JDK can be built for a variety of operating system platforms
148 and hardware architectures. The resulting builds are always placed in a
149 directory which contains the platform and architecture as part of the
150 pathname, as in *platform*-*arch*. For example, if you build the jdk
151 project on a Linux platform running on x86 hardware, the resulting build
152 will be in:
153
154 *install-dir*/jdk/build/linux-i586
155
156 We've provided support for some platforms and architectures in
157 common/architectures. Add another, if your needs require it.
158
159 Provided NetBeans projects
160 This section describes the NetBeans projects that help you work on
161 particular parts of the JDK. While they're largely similar in structure
162 and should work the way you expect NetBeans projects to work: edit,
163 build, test, etc. But there are some differences. They don't all support
164 the same targets (e.g., there's nothing to run in jarzip project).
165
166 Some projects are built by invoking make, since they involve compilation
167 of native code or other activities that cannot be done by javac. We call
168 these "make-based", and call all others "ant-based".
169
170 They all are configured by way of a build.properties file, which
171 specifies what subdirectories of the JDK sources they manipulate, what
172 directories contain their tests, whether they use make or ant, etc.
173
174 The very first time you open any one of these projects on set of Open
175 JDK sources, NetBeans will scan the entire set of sources, not just
176 those for the project you opened. This will take a few minutes, but will
177 ensure that Go To Type, Go To Source, and so on work as expected. Later,
178 when you open other projects on the same Open JDK sources, there will be
179 at most a slight delay.
180
181 There's a README accompanying each project. Most are text files, which
182 you can Open in NetBeans, some are HTML files, in which case unless you
183 enjoy reading raw HTML, you're better off choosing the *View* menu item
184 from the context menu, which will display the README in your web
185 browser.
186
187 Finally, note that these projects were all created by different people,
188 and are while some attempt has been made to make them look and behave
189 the same, they are maintained separately and will vary somewhat.
190
191 The projects currently provided are:
192
193 jdk (directory "jdk")
194 A convenient starting point for the other projects, and from which
195 you can build the entire OpenJDK. Please note that depending on your
196 hardware, this could take a *very* long time. The results of the
197 build are in *install-dir*/jdk/build/*platform*-*arch*.
198
199 world (directory "world")
200 This project builds both the Hotspot VM and all of JavaSE. Please
201 note that pretty much regardless of your hardware, this *will* take
202 a long time, and use *lots* of disk space (more than 3GB). The
203 results of the build are in
204 *install-dir*/build/*platform*-*arch* and
205 *install-dir*/build/*platform*-*arch*-fastdebug.
206
207 Consult the project's README file for details.
208
209 AWT & Java2d (directory "awt2d")
210 For working on AWT and Java2d. Supports running the Font2DTest demo.
211
212 This is a make-based project: In order to build this project, you
213 should build the jdk project first, since AWT and Java2d include
214 native code.
215
216 JConsole (directory "jconsole")
217 For working on JConsole. Creates ../dist/lib/jconsole.jar. Supports
218 running and debugging JConsole.
219
220 This ant-based project does *not* require that you build the jdk
221 project first, provided that you use a pre-built version of JDK 7.
222
223 Java (TM) Management Extensions (JMX(TM)) API (directory "jmx")
224 For working on JMX source code. Creates ../dist/lib/jmx.jar.
225
226 This ant-based project does *not* require that you build the jdk
227 project first, provided that you use a pre-built version of JDK 7.
228
229 Jar & Zip (directory "jarzip")
230 For working on jar & zip. It builds the zip library (including
231 native code), the jar library, and the jar tool. Creates an
232 executable jar program in ../build/*platform*-*arch*/bin/jar.
233
234 This is a make-based project: In order to build this project, you
235 should build the jdk project first, since AWT and Java2d include
236 native code.
237
238 Swing (directory "swing")
239 For working on Swing. Creates ../dist/lib/swing.jar. Supports
240 running and debugging the SampleTree demo.
241
242 This ant-based project does *not* require that you build the jdk
243 project first, provided that you use a pre-built version of JDK 7.
244
245 In addition, there are projects for building the compiler, javadoc,
246 and related tools, in the OpenJDK langtools component. These
247 projects are separate from those described here, and have their
248 own set of guidelines and conventions. For more details, see the
249 README files in make/netbeans in the OpenJDK langtools component.
250
251 Running Tests
252 We use the jtreg test harness, described more fully at
253 http://openjdk.java.net/jtreg
254
255 The OpenJDK tests are in the default Java package, are public classes,
256 and have a "static void main(String[] args)" with which they are
257 invoked. Some tests are actually shell scripts, which might compile
258 code, etc. jtreg is quite flexible.
259
260 To run tests for a project, use *Test Project* from NetBeans. From the
261 command line, you can invoke "ant jtreg" on any individual project's
262 build.xml file.
263
264 In either NetBeans of on the command line, jtreg prints summary output
265 about the pass/fail nature of each test. An HTML report of the entire
266 test run is
267
268 ../build/*platform*-*arch*/jtreg/*ant-project-name*/JTreport/report.html
269
270 In that same JTreport directory are also individual HTML files
271 summarizing the test environment, test passes and failures, etc.
272
273 More detail on any individual test is under
274
275 ../build/*platform*-*arch*/jtreg/*ant-project-name*/JTwork.
276
277 For example, details about the awt/Modal/SupportedTest/SupportedTest
278 test are under the JTwork directory at the same pathname as the test
279 itself in a ".jtr" file. For example:
280
281 ../build/*platform*-*arch*/jtreg/*ant-project-name*/JTwork/awt/Modal/SupportedTest/SupportedTest.jtr
282
283 Sometimes you will see that running jtreg has resulted in a failure.
284 This does not always mean that a test has an error in it. Jtreg
285 distinguishes between these two cases. There are a number of tests that
286 are "ignored", and not run, and these are reported as failures.
287
288 You can run a single test by right clicking on it and choosing *Run
289 File* from the context menu. Similarly, you can debug a single test by
290 choosing *Debug File*.
291
292 Debugging
293 Debugging is enabled by default in ant-based projects, as if
294 "-g:lines,vars,source" were given. You can alter these settings via
295 entries in one of the configuration properties files. For example:
296
297 javac.debug=false
298 javac.debuglevel=<debug level options>
299
300 To debug a project or test, use NetBeans in the normal way, with *Debug
301 Project* or *Debug File*. Note that not all projects provide a target
302 that can be debugged, but tests can be debugged.
303
304 Creating Javadoc
305 You can create Javadoc for any of the projects: just choose *Generate
306 Javadoc for Project* from the NetBeans menu. Your default browser will
307 open up, displaying the just-generated javadoc.
308
309 Javadoc gets generated into a separate subdirectory for each project.
310 For example, the Jar & Zip project's javadoc gets generated in
311
312 ../build/*platform*-*arch*/jtreg/*ant-project-name*/javadoc/jarzip
313
314 Cleaning projects
315 Each project can of course be cleaned. Make-based and ant-based projects
316 differ a little in what exactly gets cleaned. In both cases, all jtreg
317 results and javadoc are removed.
318
319 In ant-based projects, project-specific files as determined by the
320 project's build.properties file are removed from the classes and gensrc
321 directories that are under ../build/*platform*-*arch*.
322
323 In make-based projects, "make clean" is run in the same directories as
324 "make all" is run when building the project.
325
326 Please note that the jdk project is "special" with respect to
327 cleaning: in this case, the entire ../build directory is removed.
328 Similar for the world project.
329
330 Creating your own NetBeans project
331 The project's we've provided are hopefully a useful starting point, but
332 chances are that you want to work on something else. This section will
333 describe how to select an existing project, and then adapt it to your
334 needs.
335
336 Considerations
337 The first consideration is whether or not the code in which you're
338 interested needs anything beyond javac and copying of resources to
339 build. If so, then you'll need to create a make-based project. If not,
340 an ant-based project is possible. See the project descriptions above to
341 learn which are make-based, and which are ant-based.
342
343 The second consideration is to consider the files that you'll need. Each
344 project is defined by 3 files:
345
346 * build.xml
347 This is the ant build script. For a make-based project, they tend to
348 have a target for "make clean" and another for "make all", each of
349 which invokes "make-run" in the same set of directories. Take a look
350 at jarzip/build.xml for an example.
351
352 For an ant-based project, there might be nothing, with all the work
353 done via the declaration of properties in the build.properties file.
354 Take a look at jconsole/build.xml for an example, and notice how it
355 overrides the -pre-compile and -post-compile targets that are
356 defined in common/shared.xml (where they are defined to do nothing).
357
358 * build.properties
359 This file defines the directories (and possibly files) that are
360 included in and excluded from. Basically, a file is considered to be
361 in a project if it is mentioned in the includes list, or is
362 contained under a directory mentioned in that list, *unless* it is
363 explicitly excluded or is contained under a directory that is
364 excluded. Take a look awt2d/build.properties for an example.
365
366 * nbproject/project.xml
367 This file defines a project for NetBeans for a "freeform" project.
368 Each declares several entity references, which are used later in the
369 project. For an example, see javadoc/nbproject/project.xml, which is
370 an ant-based project. Compare that with
371 jarzip/nbproject/project.xml, which is make-based. Not much
372 difference! That's because while the jarzip project is make-based,
373 it does not have any platform-specifc native code. Contrast that
374 with awt2d/nbproject/project.xml, which does have native code;
375 notice that it uses platform-specific entity references.
376
377 In summary, we recommend exploring the given projects, and choosing one
378 that most closely suits our needs.
379
380 Example: A project for working on collections
381 Let's create a project to work with on the collections classes. There's no native
382 code here, so an ant-based project will do. Therefore, the jconsole
383 project is a reasonable project to use as a starting point.
384
385 Clone the existing project
386 Make a directory for the collections project next to the existing projects:
387
388 % mkdir -p collections/nbproject
389
390 Copy files from the jconsole project:
391
392 % cp jconsole/build.properties collections
393 % cp jconsole/build.xml collections
394 % cp jconsole/nbproject/project.xml collections/nbproject
395
396 Change the set of files included in the project
397 The collections sources are all under one directory, and we want to include
398 them all. The same is true of the tests. So edit
399 collections/build.properties so that it contains these lines:
400
401 includes=\
402 java/util/
403 excludes=\
404 java/util/Calendar.java,\
405 java/util/jar/,\
406 java/util/logging/,\
407 java/util/prefs/,\
408 java/util/regex/,\
409 java/util/spi/,\
410 java/util/zip/,\
411 **/*-XLocales.java.template
412 jtreg.tests=\
413 java/util/**/*Collection/ \
414 java/util/**/*Map/ \
415 java/util/**/*Set/ \
416 java/util/**/*List/
417
418 Notice the trailing "/" in some of those pathnames: that tells NetBeans to
419 treat the path as a directory and include (or exclude) everything beneath
420 it in the hierarchy. Note also how we include java/util, but then exclude
421 several directories under that which are not related to collections.
422
423 The build.xml for collections is about as simple as can be. First, change the
424 name of the project:
425
426 <project name="collections" default="build" basedir=".">
427
428 Then remove the -pre-compile target from the build.xml. Change the
429 -post-compile target to create collections.jar without any manifest, and
430 to only contain the collections-related classes. The jar task now looks
431 like this:
432
433 <jar destfile="${dist.dir}/lib/collections.jar">
434 <fileset dir="${classes.dir}">
435 <include name="java/util/*.class"/>
436 <exclude name="java/util/Calendar*.class"/>
437 </fileset>
438 </jar>
439
440 Also, change the clean target to remove collections.jar instead of
441 jconsole.jar.
442
443 Now edit project.xml file. NetBeans uses an internal name and a
444 user-visible name, both of which should be changed:
445
446 <name>Collections</name> <!-- Customized -->
447
448 <property name="name">collections</property> <!-- Customized -->
449
450 Inside of <ide-actions>, you'll see actions defined for "run" and
451 "debug". The Open JDK sources don't include any interesting Collections
452 demos, but leave these here for now: Chances are you'll find or create
453 some collections app of your own, and want to run and or debug it.
454
455 Now, open the Collections project in NetBeans. You'll find that it operates
456 just like all the other projects.
457
458 If/when you want to have this project run a collections demo, change the run
459 target in collections/build.xml to invoke it in whatever manner is appropriate
460 for the app. From NetBeans, you should be able to run and debug the app,
461 including setting breakpoints in collections code.
462
463 Appendix 1: Customizations
464 There are several ways to customize NetBeans projects. These projects
465 share a common structure, based on common/shared.xml and
466 common/make.xml. Because of that sharing, some mechanisms described
467 below apply to most any project.
468
469 Several properties can be user-defined (and several should not be
470 user-defined!). There are different properties files read. Some default
471 targets can be overridden.
472
473 Property files
474 When projects are started, and when when ant runs (whether from NetBeans
475 or the command line), these properties files are loaded in the order
476 shown:
477
478 ${basedir}/nbproject/private/build.properties
479 $HOME/.openjdk/${ant.project.name}-build.properties
480 $HOME/.openjdk/build.properties
481 ${basedir}/build.properties
482
483 Recall that with ant, once a property is defined, its value cannot be
484 changed, so it's "first one wins".
485
486 To set or change a property for all your projects, put the change into
487 $HOME/.openjdk/build.properties. This will affect all projects,
488 regardless of how many copies of the Open JDK sources you have
489 installed.
490
491 Let's say you have 2 copies of the Open JDK sources installed on your
492 machine. To set or change a property for only the jconsole projects, but
493 for both of them, make the change in
494 $HOME/.openjdk/${ant.project.name}-build.properties. If you wanted to
495 make the change for only one of them, do it in that project's
496 ${basedir}/build.properties or
497 ${basedir}/nbproject/private/build.properties.
498
499 Note that the ${basedir}/build.properties file is provided as part of
500 the Open JDK sources. If you want to make a change for a particular
501 project, you can do so there. To be sure that you don't ever
502 accidentally check it in to the Open JDK sources, you might prefer to
503 change it in ${basedir}/nbproject/private/build.properties.
504
505 User-definable Properties
506 You can provide your own definitions for the properties listed below. We
507 don't recommend overriding the definitions of other properties.
508
509 The following two properties should be set before you try to use the
510 projects with NetBeans or ant:
511
512 * bootstrap.jdk
513 Default: None. Please set this, normally in
514 $HOME/.openjdk/build.properties.
515
516 * jtreg.home
517 Default: None. Please set this, normally in
518 $HOME/.openjdk/build.properties.
519
520 These options are for configuring the behavior of make:
521
522 * use.make
523 Default: Not set. Set this, normally in ${basedir}/build.properties,
524 for a project which is make-based.
525
526 * make
527 Default: The right make for the platform, at the normal location, set
528 in *install-dir*/jdk/make/netbeans/common/make.xml
529
530 * make.options
531 Default: Empty string. Set this to any options you want to pass to
532 make, normally in ${basedir}/build.properties.
533
534 The remaining options are for use at your discretion:
535
536 * javac.options
537 Default: -Xlint
538
539 * javac.debug
540 Default: true
541
542 * javac.debuglevel
543 Default: lines,vars,source
544
545 * javadoc.options
546 Default: Empty string. Some projects will need to set this to
547 increase the heap for running javadoc. For example, see the jconsole
548 project.
549
550 * javadoc.packagenames
551 Default: "none". Set this only if your project has packages that
552 should be javadoc'd which are outside of those listed in the javadoc
553 target's packageset. See the jconsole project for an example.
554
555 * jtreg.tests
556 Default: None. Set this to a list of tests and/or directories
557 containing regression tests, normally in
558 ${basedir}/build.properties.
559
560 * jtreg.options
561 Default: Empty string. See http://openjdk.java.net/jtreg
562
563 * jtreg.vm.options
564 Default: Empty string. See http://openjdk.java.net/jtreg
565
566 * jtreg.samevm
567 Default: false. See http://openjdk.java.net/jtreg
568
569 User-overridable Targets
570 The following targets are provided for your convenience in customizing
571 various standard actions of the build process. The default action for
572 each one is to do nothing.
573
574 These come in pairs, allowing your scripts to take some action before or
575 after a standard action.
576
577 * -pre-init
578 Runs before any other initialization has been done.
579
580 * -post-init
581 Runs before after all other initialization has been done.
582
583 * -pre-compile
584 Runs before compilation, whether via ant or make. Note that in the
585 case of make, it is before the -build-make target has run, not after
586 each individual make-run has run.
587
588 * -post-compile
589 Runs after compilation, whether via ant or make.
590
591 * -pre-jtreg
592 Runs before regression tests are run.
593
594 * -post-jtreg
595 Runs before after regression tests are run.
596
597 In a make-based project, you should override these targets to do the
598 build and clean actions required of your project.
599
600 * -build-make
601 * -clean-make
602
603 Known Issues
604
605 Can't run nor debug a single test in the JConsole test
606 In most projects, you can run a single test by opening it in the editor,
607 and choosing Run File from the context menu. If you try this with the a
608 JConsole test, instead you'll see that *all* tests from *all* projects
609 are run. The workaround is to not try to run a single JConsole test.
610 Debugging is similarly problematic (both running and debugging use the
611 same underlying infrastructure).
612
613 If you do Run File a JConsole tests, you can always stop them by pressing
614 the stop button in the NetBeans output window. But you'll be surprised to
615 learn that they are actually still running in the background. The only
616 way out of this situation is to exit NetBeans. A few more tests will run,
617 but after restarting NetBeans things will be OK.
618
619 Attribution
620 UNIX is a registered trademark in the United States and other countries,
621 exclusively licensed through X/Open Company, Ltd.
622