OpenJDK | 易学教程

shell脚本

阅读更多关于 shell脚本

【推荐】2019 Java 开发者跳槽指南.pdf(吐血整理) >>> #!/usr/bin/env bash JAR_FILE_NAME="donkey-acl-console.war" findproc() { PID=`ps aux | grep $JAR_FILE_NAME | grep "java" | grep -v "$$" | grep -v grep | awk '{ print $2 }'` } findproc; echo 'find process id : '$PID for i in $PID do /bin/kill -9 $PID done cd `dirname $0` cd .. DEPLOY_DIR=`pwd` JAVA='java' if [ -z `which java` ]; then if [ -z $JAVA_HOME ]; then JAVA=$JAVA_HOME/bin/java else echo 'Cannot find java command and JAVA_HOME.' fi fi if [ ! -z `java -version 2>&1 | grep 'openjdk version' | awk '{print $3}' | egrep '1.[8-10].\d*'` ]; then nohup $JAVA

CentOS + Jenkins

阅读更多关于 CentOS + Jenkins

【推荐】2019 Java 开发者跳槽指南.pdf(吐血整理) >>> CentOS + Jenkins 2018.09.14 15:04:04字数 507阅读 94 1. 安装JDK 确认此前未安装过JDK，如果安装过先确认jdk不是gcj版本，否则Jenkins可能运行异常，需要卸载重装JDK；查看jdk版本 # java -version 卸载jdk # yum remove java 搜索open-jdk # yum search openjdk image.png 安装open-jdk # yum install java-1.8.0-openjdk 再检查JDK版本 [root @localhost ~]# java -version openjdk version "1.8.0_161" OpenJDK Runtime Environment (build 1.8.0_161-b14) OpenJDK 64-Bit Server VM (build 25.161-b14, mixed mode) 2. 安装GIT，如果已安装则跳过 yum install git 3. 开始安装Jenkins 下载依赖 wget -O /etc/yum.repos.d/jenkins.repo http://jenkins-ci.org/redhat/jenkins.repo

Strange NullPointerException Catch in OpenJDK JAXB Implementation

阅读更多关于 Strange NullPointerException Catch in OpenJDK JAXB Implementation

问题 I found some strange code in OpenJDK JAXB: com.sun.xml.internal.bind.v2.model.impl.ModelBuilder try { XmlSchema s = null; s.location(); } catch (NullPointerException e) { // as expected } catch (NoSuchMethodError e) { ... } Can some explain why they do this? Or this is just a bad code need to fix. 回答1: They are using this code as a test to determine which version of the JAXB (JSR-222) APIs are being used. The location parameter was added to @XmlSchema in JAXB 2.1, if NoSuchMethodError was

Client ECC SSL Certificate contains “unknown named curve”

阅读更多关于 Client ECC SSL Certificate contains “unknown named curve”

问题 Question precontext: I am working in an existing library that uses SSL with the netty framework on a remote server. I am running into an SSL/TLS handshake error. The error is as follows: javax.net.ssl.SSLProtocolException: java.io.IOException: Unknown named curve: 1.2.840.10045.3.1.1 at sun.security.ssl.Handshaker.checkThrown(Handshaker.java:1345) ~[na:1.7.0_79] at sun.security.ssl.SSLEngineImpl.checkTaskThrown(SSLEngineImpl.java:519) ~[na:1.7.0_79] at sun.security.ssl.SSLEngineImpl

javac error message does not display entire filepath

阅读更多关于 javac error message does not display entire filepath

问题 When using javac (or the ant task ), the error message does not include the entire filepath, it only includes the file name. For example, $ javac src/path/to/Filename.java Filename.java:1: package foo.bar does not exist import foo.bar.Baz; ^ What I would like is, $ javac src/path/to/Filename.java src/path/to/Filename.java:1: package foo.bar does not exist import foo.bar.Baz; ^ My problem is that vim quickfix does not work if it's not given the entire filepath, not just the filename. With just

How to know if I am using Open JDK or Oracle JDK?

阅读更多关于 How to know if I am using Open JDK or Oracle JDK?

问题 Using java -version gives me this. java version "1.7.0_80" Java(TM) SE Runtime Environment (build 1.7.0_80-b15) Java HotSpot(TM) 64-Bit Server VM (build 24.80-b11, mixed mode) Is it an OpenJDK or OracleJDK ? 回答1: I think that you're using OracleJDK. As I saw with a google search, the openJDK --version output is like this: java -version openjdk version "1.8.0-internal" OpenJDK Runtime Environment (build 1.8.0-internal-0) OpenJDK 64-Bit Zero VM (build 25.0-b20-internal, interpreted mode) See:

Java component not updating most of the time

阅读更多关于 Java component not updating most of the time

问题 I think I may have found a platform issue with openjdk-1.8.0_45 under ubuntu 15.04. The following program compiles and runs: import java.awt.*; import java.awt.event.*; import java.util.*; import javax.swing.*; import javax.swing.Timer; public class TimerTime extends JPanel implements ActionListener { private JLabel timeLabel; public TimerTime() { timeLabel = new JLabel( String.valueOf(System.currentTimeMillis()); add( timeLabel ); Timer timer = new Timer(50, this); timer.setInitialDelay(1);

Trying to use SonarQube on Jenkins to analyze project, but Jenkins using JDK 1.7 and I am getting an unsupported major.minor version error

阅读更多关于 Trying to use SonarQube on Jenkins to analyze project, but Jenkins using JDK 1.7 and I am getting an unsupported major.minor version error

问题 I'm trying to analyze a git project using SonarQube and running that through Jenkins, however the Console Output gives me an error when I try to build. java.lang.UnsupportedClassVersionError: org/sonar/batch/bootstrapper/ EnvironmentInformation : Unsupported major.minor version 52.0 Screenshot -> http://i.imgur.com/Jb7Wngu.png Which I have learned means I'm using a higher JDK at compile time than I am at runtime. When I ssh into the machine that is hosting Jenkins and the SonarQube server and

How do I cast a List from a subclass generic to a parent class generic?

阅读更多关于 How do I cast a List from a subclass generic to a parent class generic?

问题 I'm modifying open JDK to add features and I've run into this twice with no good solution. There's a class named JCStatement which extends JCTree . Issue: I want to cast a List<JCStatement> into a List<JCTree> . It's clear that a class can reference one of its extensions, but when I have it on a List, it just doesn't work. I used: (List<JCTree>)((List<?>)params) to cast, which works, but doesn't build on ant. IDE gives me the following warning: Type safety: Unchecked cast from List<capture#1

Liunx安装更换JDK

阅读更多关于 Liunx安装更换JDK

Linux安装JDK完整步骤 1.查看系统jdk版本运行命令： java -version openjdk version "1.8.0_102" OpenJDK Runtime Environment ( build 1.8.0_102-b14 ) OpenJDK 64-Bit Server VM ( build 25.102-b14, mixed mode ) 根据系统显示为主，以上代码仅供展示 2.检测jdk安装包运行命令： rpm -qa | grep java java-1.7.0-openjdk-1.7.0.111-2.6.7.8.el7.x86_64 python-javapackages-3.4.1-11.el7.noarch tzdata-java-2016g-2.el7.noarch javapackages-tools-3.4.1-11.el7.noarch java-1.8.0-openjdk-1.8.0.102-4.b14.el7.x86_64 java-1.8.0-openjdk-headless-1.8.0.102-4.b14.el7.x86_64 java-1.7.0-openjdk-headless-1.7.0.111-2.6.7.8.el7.x86_64 运行命令依次删除上述插件（保留python、javapackages）运行命令：