OpenJDK

Java, Apache HttpClient, TLSv1.2 & OpenJDK 7

ぐ巨炮叔叔 提交于 2019-12-03 20:23:58
We have a small group of Tomcat servers running OpenJDK v1.7.0_111. We have plans to upgrade them and migrate them this summer but we've found that a client API we interact with is moving to require TLSv1.2 in the near term. My ultimate desire is to find a configuration change to allow for this. The application hosted there creates it's SSL context in a pretty straight forward way: SSLContext sslContext = SSLContexts.createDefault() SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslContext); SSLContexts is from Apache's httpclient library (version 4.4.1) and is also pretty

Complete list of JVM options [duplicate]

这一生的挚爱 提交于 2019-12-03 18:49:02
问题 This question already has answers here : Print All JVM Flags (2 answers) Closed 7 months ago . Besides official documentation I have found only this post. But it is quite old and incomplete (only -XX options available). For example, I couldn't find -XX:AutoBoxCacheMax option in none of them. Where the complete list can be found if it exists? 回答1: You can use java -XX:+UnlockDiagnosticVMOptions -XX:+PrintFlagsFinal -version to print all options and their defaults. If you have a debug build you

OpenJDK breaks on processWorkerExit with no breakpoint

被刻印的时光 ゝ 提交于 2019-12-03 18:47:41
问题 I'm running tomcat 7.0.21 on OpenJDK java version "1.6.0_20" OpenJDK Runtime Environment (IcedTea6 1.9.9) (6b20-1.9.9-0ubuntu1~10.10.2) OpenJDK 64-Bit Server VM (build 19.0-b09, mixed mode) in debug mode via Eclipse. Periodically after serving an arbitrary number of requests, OpenJDK starts to break at: At this point there is very little stack left, usually: and very little to go on as far as what might have cause the issue... Anyone have any insight on what might be happening? 回答1: In debug

阿里巴巴开源 Dragonwell JDK 最新版本 8.1.1-GA 发布

旧城冷巷雨未停 提交于 2019-12-03 18:41:15
导读 :新版本主要有三大变化:同步了 OpenJDK 上游社区 jdk8u222-ga 的最新更新;带来了正式的 feature:G1ElasticHeap;发布了用户期待的 Windows 实验版本 Experimental Windows version。 距离 Dragonwell JDK 第一个正式版本 8.0.0-GA 发布已经过去 3 个月了,项目在 Github 上的 stars 继续攀升达到了 1900。今天我们带来了最新版本 8.1.1-GA 的发布,包含了全新的特性和更新。详情见下文。 龙井 8.1.1-GA 的新变化 新版本里我们同步了 OpenJDK 上游社区 jdk8u222-ga 的最新更新,带来了上游稳定版本的最新安全更新和补丁。 在 8.0.0-GA 发布的时候,我们介绍了 Dragonwell 第三个新特性 ElasticHeap 的一些情况,很多用户已经跃跃欲试了,这次发布我们带来了正式的 feature:G1ElasticHeap。能够在不影响 Java 业务运行的前提下,动态节约 Java 进程物理内存。 另外,我们还发布了用户期待的 Windows 实验版本 Experimental Windows version,使用 Windows 开发的小伙伴们可以更加方便的使用 Dragonwell JDK 进行相应的开发工作。

Circle approximations using Bezier curves

狂风中的少年 提交于 2019-12-03 16:46:56
I have 2 questions about bezier curves, and using them to approximate portions of circles. Given the unit circle arc (1,0)->(cos(a),sin(a)) where 0 < a < pi/2, will it result in a good approximation of this arc to find the bezier curve's control points p1, p2 by solving the equations imposed by the requirements B(1/3) = (cos(a/3), sin(a/3)) and B(2/3) = (cos(2a/3), sin(2a/3)). (In other words, requiring that the bezier curve go through two evenly spaced points in the arc). If we have an affine transformation A which turns the circle arc in an ellipse arc will the transformed control points Ap0

Fonts slightly wider in OpenJDK vs OracleJDK

点点圈 提交于 2019-12-03 16:27:34
问题 I'm noticing differences in font spacing using OpenJDK compared to OracleJDK. I've narrowed this down to the fonts. They are rendered by OpenJDK ever so slightly wider... Careful visual inspection of the screenshot above shows the character widths are identical, the only difference is the spacing. I also confirmed this with programmatic check of font metrics for all characters A-Za-z0-9. e.g. the String "Dialog - plain" at 12pt is 125px wide in OpenJDK - my build of 8u131-b11 125px wide in

JavaFX on Linux

我与影子孤独终老i 提交于 2019-12-03 16:10:32
问题 What is the situation with JavaFX on Linux (x86 and x64)? Can a JavaFX app be executed without problems on Linux OS? I have found some questions from years 2011 and 2012, when apps were not stable! 回答1: The current version of JFX released is 2.2.4 and it is quite stable on Linux. However, it will become very much better when Java 8 would be released as it would contain JFX 8 distibution. You can try it yourself now using java 8 early access builds. 回答2: JavaFX 8 runs fine on Linux in my

微软宣布加入 OpenJDK 项目

大憨熊 提交于 2019-12-03 14:10:44
近日,微软的 Bruno Borges 在 OpenJDK 邮件列表中发布了一条消息,内容包含接下来发生的事情以及微软如何开始将其团队整合到 OpenJDK 社区。在邮件中,Bruno Borges 提到,微软已正式签署《Oracle 贡献者协议》。同时,他重申了微软对 Java 的承诺,以及微软团队对回馈 Java 社区的期待。 Borges 曾经是 Oracle 开发人员,现在担任微软 Java 的首席产品经理。他向大家介绍了 Java 工程团队负责人 Martijn Verburg,Verburg 同时也是 jClarity 的首席执行官,而 jClarity 是 AdoptOpenJDK 的主要贡献者,于今年 8 月被微软收购。 该邮件可以在 OpenJDK 邮件列表 中找到: 嗨,OpenJDK 社区, 在过去的一周中,微软正式签署了《Oracle 贡献者协议》,甲骨文公司对我们参与该项目表示了认可及欢迎。我代表微软 Java 工程团队,很高兴正式加入 OpenJDK 项目,并期待与你们的合作。 众所周知,微软及其子公司在许多方面都高度依赖 Java,并且在微软 Azure 云中向客户提供 Java 运行时服务。微软已经认识到在甲骨文成功有效管理下的 OpenJDK 项目所获得的巨大价值,它收购了 Java,得到了更广泛的软件生态系统,我们也期待做出自己的一份贡献。

jdk/java 11环境变量设置

我与影子孤独终老i 提交于 2019-12-03 12:06:42
新版本的java或jdk设置环境变量时,仅设置“PATH”就可以了。不用再设置“JAVA_HOME”和“CLASSPATH”。 Ubuntu Kylin 优麒麟 下载jdk https://www.oracle.com/technetwork/java/javase/downloads/jdk11-downloads-5066655.html 安装jdk, sudo dpkg -i jdk*.deb 设置系统环境变量,在/etc/profile文件中最后添加2行: PATH=/usr/lib/jvm/jdk-11.0.3/bin:$PATH export PATH 其中“/usr/lib/jvm/jdk-11.0.3/bin”为jdk的安装路径,请根据实际路径修改。 当然,也可以设置属于用户自己的环境变量。文件为~/.bashrc或~/.profile。 使环境变量生效, source /etc/profile 查看java版本, java -version 当然,为了保持与tomcat等软件的兼容性,避免手工指定java的位置,添加环境变量“JAVA_HOME”也是可以的。 windows 10 安装jdk。 控制面板,系统和安全,系统,高级系统设置,高级,环境变量。 下方的“系统变量”选择框中选择path,单击“编辑”按钮,在“变量值”文本框的起始位置添加“C:\Program

How can I restart JVM on OutOfMemoryError _after_ making a heap dump?

亡梦爱人 提交于 2019-12-03 11:40:47
问题 I know about the -XX:+HeapDumpOnOutOfMemoryError JVM parameter. I also know about -XX:OnOutOfMemoryError="cmd args;cmd args" and that kill -3 <JVM_PID> will request a heap dump. Question: How can I make sure that I, on OutOfMemoryError , first make a full heap dump and then force a restart (or kill) after the dump is done? Is my best bet -XX:OnOutOfMemoryError="kill -3 %p;sleep <time-it-takes-to-dump>;kill -9 %p" ? 回答1: java -XX:+HeapDumpOnOutOfMemoryError -XX:OnOutOfMemoryError="kill -9 %p"