Deepak Bhole Sr. Software Engineer, Red Hat Inc. May

Transcription

1

2 Java - From to Red Hat Enterprise Linux and What Lies Ahead Deepak Bhole Sr. Software Engineer, Red Hat Inc. th May /06/11

3 / Red Hat's role Persistent index will always show current point Agenda Questions This presentation is designed to be used with audio as a primary mode of content delivery. If you have downloaded it, see notes section for rough notes on applicable slides (draft quality). For pdf, it should be at the end of the slide deck.

4 / Red Hat's role Timeline: Java 1.1 Java Java 1.4 Java Java ? Java 7 Java LibGCJ Classpath Questions Java GCJ Plugin sources GPLd GCJ stands for GNU Compiler for Java GPL stands for GNU General Public License ++

5 / What? vs JDK Community Apple Questions + JDK stands for Java Development Kit All company logos are copyright by their respective owners

6 vs JDK (current) / What? vs JDK Current Future Questions Deployment tools HotSpot Virtual machine Interpreter JIT (Just In Time) compiler Tools (javac, javadoc, etc.) Class libraries Public API (Application Programming Interface) JDK

7 vs JDK (future) / What? vs JDK Current Future Questions Deployment tools Serviceability tools HotSpot Virtual machine Interpreter JIT compiler Tools (javac, javadoc, etc.) Class libraries Public API JDK

8 6 vs JDK6 / What? vs JDK 6 7 Questions JDK6 (closed) JDK7 (7) 6 Proprietary Semi-open (development in open + some proprietary patches) Open

9 7 vs JDK7 / Deployment tools Serviceability tools? What? vs JDK 6 7 Tools (javac, javadoc, etc.) Class libraries HotSpot Virtual machine Interpreter JIT compiler Public API Questions + As heard at JavaOne JDK Closed 95%+ 5%+

10 What is? / What? Why? -Web Questions Image sources:

11 Some of the contributors / What? Who is involved? Why? -Web Questions (-Web only) (Indirectly through ) All logos are copyright by their respective owners

12 Some of the users / What? Who is involved? Why? -Web Questions (-Web only)

13 Why was created? / What? Why? -Web Build (For the first release) Questions Image sources:

14 To fix the build / What? Why? -Web Build Questions Image sources:

15 To fill what's missing / What? Why? -Web Implemented independently Deployment tools Questions Deployment tools HotSpot Virtual machine Interpreter JIT compiler Tools (javac, javadoc, etc.) Class libraries JDK

16 To back patch fixes / What? Why? -Web Implemented independently Deployment tools Questions Deployment tools HotSpot Virtual machine Interpreter JIT compiler Tools (javac, javadoc, etc.) Class libraries JDK

17 To support additional architectures / What? Why? -Web Shark/Zero Implemented independently Deployment tools Questions Deployment tools HotSpot Virtual machine Interpreter JIT compiler Tools (javac, javadoc, etc.) Class libraries Image sources: JDK

18 To support additional tools / What? Why? -Web Shark/Zero Implemented independently Deployment tools Questions Deployment tools HotSpot Virtual machine Interpreter JIT compiler Tools (javac, javadoc, etc.) Class libraries JDK

19 Fixes (with ) / What? Why? -Web I found a bug, here is the patch! Thanks! It will be in the next update whenever it happens* Questions * has a slower release cycle and it is not set in advance Image sources:

20 Fixes (with ) / What? Why? -Web I found a bug, here is the patch! Thanks! It will be in the next update soon*! Questions * has a faster release cycle dictated by importance of fixes since last release

21 Fixes (with ) / What? Why? -Web I found a bug, here is the patch! Thanks! It will be in the next update soon! Here is a nice patch from Mr. Green. Thanks! It will be in the next update! Questions.. No problem! We will maintain it locally till then.

22 Co-ordinated security / What? Why? -Web Update planned Patches sent Distros notified Public release JDK Distros Questions Not in code base In code base, not public In code base, public All company logos are copyright by their respective owners

23 -Web / What? Why? -Web Web Browser Plugin Web Start (javaws) Settings tool (itweb-settings) Questions Image sources:

24 Fully Open Source / What? Why? -Web LGPL GPL + Classpath Exception Questions GPL stands for GNU General Public License LGPL stands for GNU Lesser General Public License Image source:

25 Completeness / What? Why? -Web Plugin is almost fully complete Questions Web Start is slightly lagging, but has support for all of the widely used features

26 Co-ordinated security / What? Why? -Web Update planned Distros notified Public release Distros Questions Not in code base In code base, not public In code base, public

27 Settings configuration tool / What? Why? -Web Questions

28 Settings configuration tool / What? Why? -Web Questions

29 6 / -Web Upstream RHEL/Fedora Questions 6 commits Red Hat Others Total Red Hat commits: 2159 out of 2587* * Approximate numbers as of 17:00 EDT on

30 (7) / -Web Upstream RHEL/Fedora Questions (7) commits Red Hat Others Total Red Hat commits: 1988 out of 2432* * Approximate numbers as of 17:00 EDT on

31 Role in -Web / -Web Upstream RHEL/Fedora Questions -Web commits Red Hat Others Total Red Hat commits: 223 out of 234* * Approximate numbers as of 17:00 EDT on

32 6 contribution / -Web Upstream RHEL/Fedora Questions 7 Majority of 6 commits are backports The backport process 6 Red Hat is the primary backporter for 6

33 7 contribution / -Web Upstream RHEL/Fedora Questions 7 commits (Logarithmic) Oracle+Community Google Red Hat Apple As of , 16:00 EDT* Total: 8337 Oracle + community: 7998 Google: 136 (1.63%) Red Hat: 127 (1.52%) Apple: 76** (0.09%) * Figures are approximate, and do not account for merge commits ** Apple's contributions have been normalized from 81/8889 (OSX port) to 76/8337

34 * contribution 6 commits / -Web Upstream RHEL/Fedora out of 2587, 83.4% Red Hat Others (7) commits out of 2431, 81.7% Red Hat Others -Web commits Questions out of 234, 95.3% Red Hat Others

35 RPM in RHEL / -Web Upstream RHEL/Fedora RPM Questions + RPM stands for RPM Package Manager

36 Upstream first policy / -Web Upstream RHEL/Fedora RPM Accepted upstream Questions RHEL release release release Red Hat Enterprise Linux release is subject to results of: TCK tests Jtreg tests Mauve tests Spec* tests Java2dBenchmark tests JFCMark tests (api, compiler, dev) (regression) (class library) (performance) (drawing perf.) (swing perf.)

37 Prioritized release Accepted upstream / -Web Upstream RHEL/Fedora RPM release Release subject to results of: release Questions Prioritized release TCK (api, compiler, dev) tests JTreg (regression) tests Mauve (class library) tests Spec* (performance) tests Java2dBenchmark (drawing perf.) tests JFCMark (swing perf.) tests

38 Links I will be at Campground 3 from 2PM to 3PM today : : -Web: Bugs: RHEL/Fedora bugs: Mailing List: distro-pkg-dev@openjdk.java.net IRC: irc.oftc.net, #openjdk Deepak Bhole dbhole@redhat.com dbhole on irc

39 Java 7

40 JMX Enhancements / ManagementFactory.getAllPlatformMXBeanInterfaces() Everything inherits from PlatformManagedObject New MBeans java.lang.management.bufferpoolmxbean java.lang.management.platformloggingmxbean JMX enhancements Language changes nio2 Fork/Join framework Rest.. Questions.. + JMX stands for Java Management Extensions

41 Switches in String / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

42 Switches in String / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

43 try-with-resources try1 / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

44 try-with-resources try2 / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

45 try-with-resources try3 / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

46 try-with-resources in JDK7 / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

47 What JDK7 does (approximately) / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

48 The AutoCloseable Interface / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

49 Diamond operator / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

50 Diamond operator / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

51 Diamond operator / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals // prints 1 // prints 2 Example posted to coin-dev list by Neal Gafter (neal@gafter.com)

52 Binary Literals / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

53 Binary Literals / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

54 Underscores in numeric literals / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

55 Regular catch / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

56 Multi-catch in JDK 7 / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

57 Precise re-throw in JDK7 / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

58 Safe var-args / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals With JDK6 (-Xlint:unchecked): warning: [unchecked] unchecked generic array creation of type java.util.list<java.lang.string>[] for varargs parameter printall(l1, l2); ^ With JDK7 (-Xlint:unchecked): warning: [unchecked] Possible heap pollution from parameterized vararg type T public <T> void printall(t params) { ^ warning: [unchecked] unchecked generic array creation for varargs parameter of type List<String>[] printall(l1, l2); ^

59 Safe var-args / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals With JDK6 (-Xlint:unchecked): No warnings With JDK7 (-Xlint:unchecked): warning: [unchecked] Possible heap pollution from parameterized vararg type T public <T> void printall(t params) { ^

60 Safe var-args / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals With JDK6 (-Xlint:unchecked): No warnings With JDK7 (-Xlint:unchecked): No warnings

61 Safe var-args / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals With JDK6 (-Xlint:unchecked): Error due not being defined Warning at line 110 With JDK7 (-Xlint:unchecked): No warnings

62 / JMX enhancements Language changes nio2 Fork/Join framework Rest.. Questions.. NIO2

63 File actions / JMX enhancements Language changes nio2 Fork/Join framework Rest.. Questions.. Actions provided by class Files copy() move() delete() create[symbolic]link() walkfiletree() etc.

64 Attributes / JMX enhancements Language changes nio2 Fork/Join framework Rest.. Questions.. *AttributeView(s) File/Directory Basic creation time access time modification time size isfile isdirectory islink getowner setowner FileOwner get/setpermissions POSIX get/setgroup

65 Asynchronous I/O / Application thread I/O thread (sys) I/O request Process I/O request Continue normal execution Process callback handler JMX enhancements Language changes nio2 Fork/Join framework Rest.. Questions.. OR Application thread I/O request (returns Future<Integer>) Continue normal execution, process Future<Integer> later

66 Change notification / JMX enhancements Language changes nio2 Fork/Join framework Rest.. Questions.. Application Thread Use WatchService sleep/wait Continue normal execution JVM Thread OS/Poll

67 Fork/Join Framework / Thread 2: Foo.compute() Foo.compute() Thread N: Foo.compute() Thread 1: JMX enhancements Language changes nio2 Fork/Join framework Rest.. Fork/Join Framework invokeall() class Foo extends RecursiveAction { public Foo(data) { } public void compute() { if (small) dolocally(); else invokeall(new Foo(halfData), // first half new Foo(otherHalfData)); // remaining } Questions.. }

68 Additional Java 7 features / JSR-292 (invokedynamic) JDBC 4.1 Unicode 6.0 Full list at JMX enhancements Language changes nio2 Fork/Join framework Rest.. Questions..

69 Java 8

70 Jigsaw / Jigsaw Lambda Language changes Questions.. JDK broken into modules based on functionality No more CLASSPATH New format to replace JAR files RPM auto-dependency writing (would be done by distros)

71 Lambda (Closures) / Jigsaw Lambda Language changes Questions.. Not yet finalized Cleaner syntax and more scalable than Anonymous Inner Classes Defender methods

72 Language Changes (Project Coin) / Collections enhancements Jigsaw Lambda Language changes Collection literals final List<Integer> digits = [4, 3, 4]; final Set<Integer> primes = { 2, 3, 5, 7 }; final Map<Integer, String> platonicsolids = { Questions.. : : : : : "tetrahedron", "cube", "octahedron", "dodecahedron", "icosahedron" }; Numeric suffixes for byte(y/y) and short (s/s) byte b = 0xA0y; short s = 0xA0s;

73 Questions? / I will be at Campground 3 from 2PM to 3PM today : : -Web: Bugs: RHEL/Fedora bugs: Questions.. Mailing List: distro-pkg-dev@openjdk.java.net IRC: irc.oftc.net, #openjdk Deepak Bhole dbhole@redhat.com dbhole on irc

74

75

76 Java - From to Red Hat Enterprise Linux and What Lies Ahead Deepak Bhole Sr. Software Engineer, Red Hat Inc. May 5th /06/11

77 / Red Hat's role Persistent index will always show current point Agenda Questions This presentation is designed to be used with audio as a primary mode of content delivery. If you have downloaded it, see notes section for rough notes on applicable slides (draft quality). For pdf, it should be at the end of the slide deck.

78 / Red Hat's role Timeline: Java 1.1 Java Java 1.4 Java Java ? Java 7 Java LibGCJ Classpath Questions Java GCJ Plugin sources GPLd GCJ stands for GNU Compiler for Java GPL stands for GNU General Public License ++ Only critical releases mentioned: 1.1 Feb in in 2002 Java 5 (Generics, major syntax changes) in 2004 Java 6 in 2006 OSS dev continued with GCJ release in 1999 and classpath started picking up around then GCJ WebPlugin in 2003 In Nov. 2006, Java/GPL announcement was made No release since then, breaking the 2-yr cycle Java 7 set for July 28th, 2011 Java for end of 2012

79 / What? vs JDK Community Apple Questions + JDK stands for Java Development Kit All company logos are copyright by their respective owners This is where most of Java is now developed Oracle, Red Hat, Google, Apple, IBM and others contribute here Most of the code base is identical to that of proprietary JDK Certain things are missing, like the plugin, javaws and some other components

80 vs JDK (current) / What? vs JDK Current Future Questions Deployment tools HotSpot Virtual machine Interpreter JIT (Just In Time) compiler Tools (javac, javadoc, etc.) Class libraries Public API (Application Programming Interface) JDK Current state: Class library, VM, compiler, etc. are open Same public API Deployment tools (plugin, webstart, etc.) will remain closed

81 vs JDK (future) / What? vs JDK Current Future Questions Deployment tools Serviceability tools HotSpot Virtual machine Interpreter JIT compiler Tools (javac, javadoc, etc.) Class libraries Public API JDK Future: Most of the items will stay open In addition to deployment tools, serviceability tools (e.g Mission Control), will stay closed JRockit-ported VM enhancements will be open

82 6 vs JDK6 / What? vs JDK 6 7 Questions JDK6 (closed) JDK7 (7) 6 Proprietary Semi-open (development in open + some proprietary patches) Open JDK6 and 6 development is not parallel, and hence the divergence 6 was created from 7 by removing the Java 7 specific parts 6 gets backports from 7

83 7 vs JDK7 / What? vs JDK 6 7 Deployment tools Serviceability tools? HotSpot Virtual machine Interpreter JIT compiler Tools (javac, javadoc, etc.) Class libraries Public API Questions + JDK Closed 95%+ 5%+ As heard at JavaOne Siblings from same codebase Around 95% of the code base will be identical

84 What is? / What? Why? -Web Questions Image sources: Based Contains core, plus build scripts, plus patches, etc.

85 Some of the contributors / What? Why? -Web Who is involved? Questions (-Web only) (Indirectly through ) All logos are copyright by their respective owners Oracle is an indirect contributor via RedHat is biggest contributor to Linux distros are not the only consumers

86 Some of the users / What? Why? -Web Who is involved? (-Web only) Questions Used by almost all major Linux distros: Fedora, RHEL, Ubuntu, Debian, SuSE, etc. -Web runs on FreeBSD

87 Why was created? / What? Why? -Web Build (For the first release) Questions Image sources: Initial drop did not build easily Needed proprietary JDK to build

88 To fix the build / What? Why? -Web Build Questions Image sources: was primarily created to fix the build issues and create a re-distributable JDK based on.

89 To fill what's missing / What? Why? -Web Implemented independently Deployment tools Questions Deployment tools HotSpot Virtual machine Interpreter JIT compiler JDK Tools (javac, javadoc, etc.) Class libraries has gradually taken on other roles It provides missing components

90 To back patch fixes / What? Why? -Web Implemented independently Deployment tools Questions Deployment tools HotSpot Virtual machine Interpreter JIT compiler JDK Tools (javac, javadoc, etc.) Class libraries It provides backward patch maintenance for up to n-2 releases

91 To support additional architectures / What? Why? -Web Shark/Zero Implemented independently Deployment tools Questions Deployment tools HotSpot Virtual machine Interpreter JIT compiler JDK Tools (javac, javadoc, etc.) Class libraries Image sources: It provides additional runtime support. Most notably Shark/Zero so that can run on other platforms. Almost all of the Shark/Zero porting work was done by Red Hat. also supports Cacao and JamVM (as an alternate to the HotSpot VM, with the class libraries)

92 To support additional tools / What? Why? -Web Shark/Zero Implemented independently Deployment tools Questions Deployment tools HotSpot Virtual machine Interpreter JIT compiler JDK Tools (javac, javadoc, etc.) Class libraries It provides additional tooling support, like for VisualVM (now via a separate visualvm-harness project under the umbrella)

93 Fixes (with ) / What? Why? -Web I found a bug, here is the patch! Thanks! It will be in the next update whenever it happens* Questions * has a slower release cycle and it is not set in advance Image sources: Patches submitted to can take an arbitrary amount of time depending on when the next release happens.

94 Fixes (with ) / What? Why? -Web I found a bug, here is the patch! Thanks! It will be in the next update soon*! Questions * has a faster release cycle dictated by importance of fixes since last release Patches submitted to have a faster turnaround as releases more frequently, and depending on the severity of the issue, can do a more immediate release if needed.

95 Fixes (with ) / What? Why? -Web I found a bug, here is the patch! Thanks! It will be in the next update soon! Here is a nice patch from Mr. Green. Thanks! It will be in the next update! No problem! We will maintain it locally till then. Questions.. Behind the scenes, developers make sure that the patch is okay for, and then take on the responsibility of local patch maintenance until the next update (assuming it was accepted) Sometimes fixes are not accepted, in which case will maintain them locally

96 Co-ordinated security / What? Why? -Web Update planned Patches sent Distros notified Public release JDK Distros Questions Not in code base In code base, not public In code base, public All company logos are copyright by their respective owners When a security update is planned, Oracle gets the patches ready and notifies Red Hat and select others. developers then put together a release, and send a preview copy to trusted distro maintainers for testing. On a preset date and time, Oracle makes the vulnerabilities public and distros release updates thereafter

97 -Web / What? Why? -Web Web Browser Plugin Web Start (javaws) Settings tool (itweb-settings) Questions Image sources: Web contains: The plugin Webstart itweb-settings

98 Fully Open Source / What? Why? -Web LGPL GPL + Classpath Exception Questions GPL stands for GNU General Public License LGPL stands for GNU Lesser General Public License Image source: All the code is -Web is Open Source. Parts from NetX are under LGPL, the plugin/javaws is GPL+Classpath, while the settings tool is GPL

99 Completeness / What? Why? -Web Plugin is almost fully complete Web Start is slightly lagging, but has support for all of the widely used features Questions Chart is more to show comparative completeness. WebStart is slightly lagging. However, both components contain the widely used features. Most of the missing features are obscure/not commonly seen in everyday applications

100 Co-ordinated security / What? Why? -Web Update planned Distros notified Public release Distros Questions Not in code base In code base, not public In code base, public As with, when a security release is due, distros are notified earlier and sent an encrypted tarball so that they can test the fixes.

101 Settings configuration tool / What? Why? -Web Questions Screenshot of settings tool showing proxy settings

102 Settings configuration tool / What? Why? -Web Questions Screenshot of settings tool showing security configuration

103 6 / -Web Upstream RHEL/Fedora Questions 6 commits Red Hat Others Total Red Hat commits: 2159 out of 2587* * Approximate numbers as of 17:00 EDT on #!/bin/bash USERS="ahughes aph dbhole fitzsim fkung gbenson iivan jon.vanalten jsumali keiths kgallowa langel mwong omajid ptisnovs jvanek asu dlila mark@klomp.org" TOTAL=`hg log grep "user:" grep -E "$USERS" wc -l` TOTALCOMMITS=`hg log grep changeset wc -l` # Filter out Andrew's commits before he joined Red Hat ANDREWS_RH_COMMITS=`hg log --date " to " grep "user:" grep andrew grep -v redhat.com wc -l` TOTAL=`echo $TOTAL + $ANDREWS_RH_COMMITS bc -l` echo "Total: $TOTAL" echo "Total commits: $TOTALCOMMITS"

104 (7) / -Web Upstream RHEL/Fedora Questions (7) commits Red Hat Others Total Red Hat commits: 1988 out of 2432* * Approximate numbers as of 17:00 EDT on See notes for previous slide for counting script

105 Role in -Web / -Web Upstream RHEL/Fedora Questions -Web commits Red Hat Others Total Red Hat commits: 223 out of 234* * Approximate numbers as of 17:00 EDT on See notes for previous slide for counting script

106 6 contribution / -Web Upstream RHEL/Fedora Questions 7 Majority of 6 commits are backports The backport process 6 Red Hat is the primary backporter for 6

107 7 contribution / 7 commits (Logarithmic) -Web Upstream RHEL/Fedora Questions Oracle+Community Google Red Hat Apple As of , 16:00 EDT* Total: 8337 Oracle + community: 7998 Google: 136 (1.63%) Red Hat: 127 (1.52%) Apple: 76** (0.09%) * Figures are approximate, and do not account for merge commits ** Apple's contributions have been normalized from 81/8889 (OSX port) to 76/8337 #!/bin/bash if [ "$1" == "redhat" ]; then USERS="langel aph andrew gbenson ptisnovs omajid dlila dbhole mwong" elif [ "$1" == "google" ]; then USERS="ahe hiroshi jjb rasbold" elif [ "$1" == "apple" ]; then USERS="astrange bino kmiller loefty rhoover swingler" else USERS="$*" fi TEMP_FILE="/tmp/jdk.commits.log" TOTAL=0 TOTALDUPLICATES=0 TOTALCOMMITS=0 for dir in. corba hotspot jaxp jaxws jdk langtools; do hg log -v -R $dir grep -E "^user: ^Reviewed-by ^Contributed-by: summary:" grep -vi merge grep -E "^user: ^Reviewed-by ^Contributed-by:" tr '\n' ' ' perl -p -e s/user:/\\nuser:/g > $TEMP_FILE for uid in $USERS; do # for each user USERS_TO_EXCLUDE=`echo $USERS sed -e s:$uid::g sed -e s:" ":" ":g -e s:"^ "::g -e s:" $"::g tr ' ' ' '` USERTOTAL=0 COUNT=`grep " $uid" $TEMP_FILE wc -l` DUPLICATED_USERS=`grep " $uid" $TEMP_FILE grep -E " $USERS_TO_EXCLUDE" wc -l` USERTOTAL=`echo $USERTOTAL + $COUNT bc -l` TOTALDUPLICATES=`echo $TOTALDUPLICATES + $DUPLICATED_USERS bc -l` TOTAL=`echo $TOTAL + $USERTOTAL bc -l` done COMMITS_IN_DIR=`wc -l $TEMP_FILE awk '{print $1}'` TOTALCOMMITS=`echo $TOTALCOMMITS + $COMMITS_IN_DIR bc -l` done rm -f $TEMP_FILE # Account for commits by Chris Phillips after he started at Red Hat ( ) if [ "$1" == "redhat" ]; then TOTAL=`echo $TOTAL + 1 bc -l` fi TOTAL=`echo $TOTAL - "($TOTALDUPLICATES/2)" bc -l` # assume duplicates == max 2 users echo "Total: $TOTAL" echo "Total duplicates: $TOTALDUPLICATES" echo "Total commits: $TOTALCOMMITS"

108 * contribution 6 commits / Web Upstream RHEL/Fedora 2159 out of 2587, 83.4% Red Hat Others (7) commits out of 2431, 81.7% Red Hat Others -Web commits Questions out of 234, 95.3% Red Hat Others

109 RPM in RHEL / -Web Upstream RHEL/Fedora RPM Questions + RPM stands for RPM Package Manager RPM contains which in turn contains

110 Upstream first policy / -Web Upstream RHEL/Fedora RPM Accepted upstream Questions RHEL release release release Red Hat Enterprise Linux release is subject to results of: TCK tests Jtreg tests Mauve tests Spec* tests Java2dBenchmark tests JFCMark tests Upstream first policy Everything is well tested (api, compiler, dev) (regression) (class library) (performance) (drawing perf.) (swing perf.)

111 Prioritized release Accepted upstream / -Web Upstream RHEL/Fedora RPM release Release subject to results of: release Questions Prioritized release TCK (api, compiler, dev) tests JTreg (regression) tests Mauve (class library) tests Spec* (performance) tests Java2dBenchmark (drawing perf.) tests JFCMark (swing perf.) tests Upstream first policy Early backports into RPMs if needed All tests are rigorously run to ensure no regressions

112 Links I will be at Campground 3 from 2PM to 3PM today : : -Web: Bugs: RHEL/Fedora bugs: Mailing List: distro-pkg-dev@openjdk.java.net IRC: irc.oftc.net, #openjdk Deepak Bhole dbhole@redhat.com dbhole on irc

113 Java 7

114 JMX Enhancements / java.lang.management.platformloggingmxbean JMX enhancements Language changes nio2 Fork/Join framework Rest.. Questions.. + ManagementFactory.getAllPlatformMXBeanInterfaces() Everything inherits from PlatformManagedObject New MBeans java.lang.management.bufferpoolmxbean JMX stands for Java Management Extensions BufferPoolMXBean: getcount getmemoryusage getname gettotalcapacity PlatformLoggingMXBean: getloggernames getloggerlevel getparentloggername setloggerlevel

115 Switches in String / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals Currently doing switch on string is somewhat cumbersome

116 Switches in String / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals Switches in string makes it cleaner String switches also use hashcode() first, so it is faster

117 try-with-resources try1 / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals Ensuring no resource leaks is tricky

118 try-with-resources try2 / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals Exceptions can occur during close too

119 try-with-resources try3 / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals Many try/catches are needed to ensure no leaks

120 try-with-resources in JDK7 / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals With Java 7 the syntax is a lot cleaner, and the VM guarantees that nothing will leak

121 What JDK7 does (approximately) / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals Java 7 also records all exceptions, not just the first/last one

122 The AutoCloseable Interface / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals The AutoCloseable interface must be implemented by all resources that want to work with try-withresources Regularly used resource (File, Network, etc.) classes in JDK7 implement AutoCloseable

123 Diamond operator / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals Current syntax is messy

124 Diamond operator / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals The compiler already knows a lot.. Java 7 makes use of that knowledge

125 Diamond operator / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals // prints 1 // prints 2 Example posted to coin-dev list by Neal Gafter (neal@gafter.com) Diamond operator and raw types are not the same despite type erasure. Avoid raw types!

126 Binary Literals / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

127 Binary Literals / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals Binary syntax makes errors less likely in cases like above

128 Underscores in numeric literals / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals Underscores make things easy to read

129 Regular catch / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals

130 Multi-catch in JDK 7 / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals Java 7 can catch multiple disjunctive exceptions at once

131 Precise re-throw in JDK7 / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals The re-throws are also precise, and there is an implicit assumptions that exceptions in the catch block are final.

132 Safe var-args / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals With JDK6 (-Xlint:unchecked): warning: [unchecked] unchecked generic array creation of type java.util.list<java.lang.string>[] for varargs parameter printall(l1, l2); ^ With JDK7 (-Xlint:unchecked): warning: [unchecked] Possible heap pollution from parameterized vararg type T public <T> void printall(t params) { ^ warning: [unchecked] unchecked generic array creation for varargs parameter of type List<String>[] printall(l1, l2); ^ Java 7 also detects possible heap pollution

133 Safe var-args / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals With JDK6 (-Xlint:unchecked): No warnings With JDK7 (-Xlint:unchecked): warning: [unchecked] Possible heap pollution from parameterized vararg type T public <T> void printall(t params) { ^ Supressing warnings works

134 Safe var-args / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals With JDK6 (-Xlint:unchecked): No warnings With JDK7 (-Xlint:unchecked): No warnings Compiler output is clean, but api user shouldn't have to supress warning related to code they did not write (target method)

135 Safe var-args / JMX enhancements Language changes Strings in switch try-with-resources Diamond operator Numeric literals With JDK6 (-Xlint:unchecked): Error due not being defined Warning at line 110 With JDK7 (-Xlint:unchecked): No warnings SafeVarargs lets method writer tell the compiler that anyone can call safely call it

136 / JMX enhancements Language changes nio2 Fork/Join framework Rest.. Questions.. NIO2

137 File actions / JMX enhancements Language changes nio2 Fork/Join framework Rest.. Actions provided by class Files copy() move() delete() create[symbolic]link() walkfiletree() etc. Questions.. Many file operations are now available

138 Attributes / JMX enhancements Language changes nio2 Fork/Join framework Rest.. *AttributeView(s) File/Directory Basic creation time access time modification time size isfile isdirectory islink getowner setowner FileOwner get/setpermissions POSIX get/setgroup Questions.. Basic file views are available for all systems, and additional ones based on filesystem are available too. Extendable via SPI

139 Asynchronous I/O / Application thread I/O thread (sys) I/O request Process I/O request Continue normal execution Process callback handler JMX enhancements Language changes nio2 Fork/Join framework Rest.. Questions.. OR Application thread I/O request (returns Future<Integer>) Continue normal execution, process Future<Integer> later The I/O can be done via Java's preset I/O threads or be processed locally later after placing the I/O call

140 Change notification / JMX enhancements Language changes nio2 Fork/Join framework Rest.. Application Thread Use WatchService sleep/wait JVM Thread OS/Poll Continue normal execution Questions.. JVM can also do file change notifications. OS method is used if available, polling otherwise

141 Fork/Join Framework / Thread 2: Thread N: Foo.compute() Thread 1: Foo.compute() Foo.compute() JMX enhancements Language changes nio2 Fork/Join framework Rest.. Fork/Join Framework invokeall() class Foo extends RecursiveAction { public Foo(data) { } public void compute() { if (small) dolocally(); else invokeall(new Foo(halfData), // first half new Foo(otherHalfData)); // remaining } Questions.. } Fork/Join is good for divide and conquer algorithms

142 Additional Java 7 features / JSR-292 (invokedynamic) JDBC 4.1 Unicode 6.0 Full list at JMX enhancements Language changes nio2 Fork/Join framework Rest.. Questions..

143 Java 8

144 Jigsaw / Jigsaw Lambda Language changes JDK broken into modules based on functionality No more CLASSPATH New format to replace JAR files RPM auto-dependency writing (would be done by distros) Questions.. JDK is too big, especially for embedded devices JigSaw will break it down A new module-info.java file will supply what the project exports, and what it needs. Thus CLASSPATH will no longer be needed A new, more enhanced format will replace JAR. Optomized for fast reading and will have content specific compression RPMS can take advantage of the dependency info to auto-generate REQs

145 Lambda (Closures) / Jigsaw Lambda Language changes Not yet finalized Cleaner syntax and more scalable than Anonymous Inner Classes Defender methods Questions.. Will be finalized in September 2011 Anonymous inner classes are bulky and have limitations (non-final vars not in scope, transparency issues, etc.) Defender methods extend interfaces. They provide default implementations for cases when implementations don't provide it. Linkage error if 2 interfaces provide the same default

146 Language Changes (Project Coin) / Collections enhancements Jigsaw Lambda Language changes final List<Integer> digits = [4, 3, 4]; final Set<Integer> primes = { 2, 3, 5, 7 }; final Map<Integer, String> platonicsolids = { Questions.. Collection literals : : : : : "tetrahedron", "cube", "octahedron", "dodecahedron", "icosahedron" }; Numeric suffixes for byte(y/y) and short (s/s) byte b short s = 0xA0s; = 0xA0y; These were originally slated for 7 and are now in Limbo. They are not guaranteed to be in 8.

147 Questions? / I will be at Campground 3 from 2PM to 3PM today : : -Web: Bugs: RHEL/Fedora bugs: Questions.. Mailing List: distro-pkg-dev@openjdk.java.net IRC: irc.oftc.net, #openjdk Deepak Bhole dbhole@redhat.com dbhole on irc

148