Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [java]

Programming language and runtime environment that allows compiled Java programs to run unchanged on most hardware and software platforms

1
vote
0answers
24 views

Connection refused for Java HTTP Server running on localhost

How would you investigate the following issue? On a specific server; any HTTP-Requests sent to a Java Server running on localhost fails with "Connection refused". (See the Java code here) In the ...
0
votes
0answers
7 views

Hyper-v dynamic memory issue with java spring boot

I have a developer who wrote several applications in Java spring boot and I have a VM configured with dynamic memory. His application stops working intermittently and he's pointing the finger at the ...
0
votes
0answers
17 views

Google Appengine unable to look up SRV record

I have an instance of mongodb running on Atlas and a Spring Boot application running on GAE trying to access this database. I have no problem running it locally but when running on GAE I see this ...
0
votes
0answers
15 views

java ldap query across domain

My active directory have structur as below: AD server URL = ldap://ldap.abc.com:389 having domain controller as below: dc=xyz,dc=abc,dc=com dc=pqr,dc=abc,dc=com Now, dc=xyz,dc=abc,dc=com has a group ...
0
votes
0answers
35 views

Disable Java in LibreOffice

I am working on deploying LibreOffice to RHEL7 workstations, and I need a way to disable LibreOffice's Java settings globally. I refer to Tools -> Options -> LibreOffice/Advanced -> "Use a ...
0
votes
0answers
30 views

Upload Generic error java.io.IOException: Permission denied

I'm seeing the blow error in my Java application which tries to upload and download files to an NFS storage. The NFS share is mounted on my server successfully and I'm able to manually write (touch ...
0
votes
0answers
13 views

Bundling multiple WAR files for in Elastic Beanstalk

Our application has multiple WAR files. I've been following the documentation here to try and bundle them, however I'm using the pre-configured Docker + Glassfish template rather than Tomcat: https://...
0
votes
0answers
12 views

How do I get a thread dump of my Wildfly process on Amazon Linux?

We're using Wildfly 11 with JDK 8 on Amazon Linux. How do I get a thread dump of our Wildfly process? We're trying to troubleshoot why we're seeing high CPU utilization for that process. We do NOT ...
0
votes
1answer
23 views

Multiple Java Keystores

I created a Keypair using the following command: "%JAVA_HOME%\bin\keytool" -genkeypair -keysize 2048 -alias tomcat -keyalg RSA -sigalg SHA256withRSA I noticed there is a key store in jdk/lib/...
0
votes
0answers
33 views

App no longer deploys to google app engine after java8 upgrade

While working on the journey of upgrading my multi-module maven java application to java 8 from java 7 i am getting an exception at the very end. Was able to work through most of the issues but i am ...
0
votes
0answers
143 views

Active Directory LDAPS and Java 181 LDAPS Verification

Java 8u181 (Java 8 Update 181) enhances security around LDAPS connections: Change: Improve LDAP support Endpoint identification has been enabled on LDAPS connections. To improve the robustness ...
0
votes
1answer
25 views

How to configure Wildfly to read environment variables

When porting an application from the Java application server GlassFish to Wildfly I noticed that applications in Wildfly report environment variables as empty, whereas GlassFish reports a value. The ...
0
votes
1answer
27 views

Java daemon keeps failing due to FileInputStreamException for config files outside its jar package

I want to implement a Java application as a daemon / service that runs on my Raspberry Pi with standard Debian Stretch (Kernel version 4.9). The java application starts but then throws an exeption ...
0
votes
0answers
55 views

browser says my server uses an unsupported protocol

I am making my site into https site. Got a Comodo certificate. Browser says: "This site can’t provide a secure connection" abs-appsupport.hhs.int.state.dp.us uses an unsupported protocol. ...
0
votes
0answers
49 views

Systemctl start embeded Tomcat fail

I have a java project with embedded Tomcat 8.5. I have add a new service to sytemd to run it as a service in CentOS 7.2. When I use "systemctl start app.service" to start the server, the program will ...
0
votes
0answers
23 views

SOLR: Installed on a new server and not able to create cores: simply stuck

I have an Ubuntu 18.04 LTS server and willing to install SOLR on it, note it is a development server with many other software on it. The installation works well: java -version java version "1.8....
0
votes
0answers
22 views

“Install New Application” tab not visible in websphere application server base

Recently I installed websphere application server base 64bit on centos os and dmgr and node agent working fine but In the console there are not options visible for create server, New application etc ...
0
votes
0answers
118 views

Where should I set context path for Tomcat?

My regular question about Tomcat. Tomcat docs about <Context>. It is NOT recommended to place elements directly in the server.xml file. But This attribute must only be used when ...
1
vote
2answers
54 views

How can I find disk space usage?

I have a Ubuntu docker run on CentOS host in Google Cloud. The docker runs a spring-boot application used for image uploading to S3. I do not save anything on local disk. Every 2 weeks or so, I have ...
0
votes
1answer
91 views

Why Nginx is so much faster than Apache in this environment?

We have a web application with a java backend and a tomcat frontend server. Before the tomcat there is an Apache. Both of them are on one host. The backend is on another host. Web browsers communicate ...
0
votes
1answer
35 views

Auto-unpacking WARs doesn't work

I have trouble with auto-unpacking WAR-files in Tomcat. My Host descriptor at server.xml (defaultHost="mp.org"): <Host name="mp.org" appBase="/var/www/mp/target/web/" unpackWARs="true" ...
1
vote
0answers
15 views

Can't find jetty config file on Fedora 28

I installed jetty8 on fedora 28, but I do not know where is the configuration file for the server. In Ubuntu the jetty8 configuration file is /etc/default/jetty8. To install jetty I've used: dnf ...
0
votes
0answers
10 views

Configure HTTPS Link for JavaEE app Tomcat

I am in a bit of a situation. I need to configure a webapp to be accessible via a secure link. I am a developer and there is a different person for system admin and servers but said person is MIA and ...
0
votes
0answers
18 views

Multiple Java installations on the same Jenkins slave

I need to have 2 version of Java on the same Docker image: Java 7 for the developers Java 8 for running a Jenkins-slave Because we're running quiet old software, the solution was: RUN echo deb http:...
0
votes
0answers
27 views

Glassfish crashes due too many open files

I am having a backend deployment running on a glassfish server, the frontend of my application sends REST request when it needs some data. Also the backend is connected to a mongo database: ...
1
vote
1answer
697 views

What does “GC (Allocation Failure)” mean in my ElasticSearch 5.6 logs?

I see these constantly in my Elasticsearch 5.6.3 logs. Is this a signal that I should scale up and add more RAM? Or is this just normal operations for ElasticSearch? [GC (Allocation Failure) [...
-1
votes
1answer
36 views

Force a specific user or application to user a specific java version

Bear with me, I'm new to sysadmin stuff. We have a server running RHEL 6 (2.6.32). We have a Pentaho application that interacts with the server as a pentaho user, and we have a team user under whose ...
0
votes
2answers
396 views

Unable to connect to oracle for java8

I've been working with setting up a few servers over the past week using Ansible. Everything has been humming along fine until today a couple of hours ago the java8 playbook I had been using quit ...
1
vote
1answer
211 views

Tomcat Tomcat/9.0.8 error java.lang.NoClassDefFoundError: javax/management/MBeanServerNotification

i am getting the following error when starting my java spring application > `16-Jul-2018 12:00:02.108 WARNING [http-nio-8080-exec-4] org.apache.catalina.loader.WebappClassLoaderBase....
0
votes
0answers
52 views

Opennms warns about Out of memory: unable to create new native thread

We have a problem where our OpenNMS instance is sending false alarms at certain times and the logs shows this: Caused by: java.lang.OutOfMemoryError: unable to create new native thread at ...
0
votes
1answer
983 views

Java Flight Recorder Docker Container

I want to profile a Java app inside a Docker container with JFR. How do I do so? The application I want to profile is not mine, so I can't alter the Dockerfile or any of the source code. Docker run ...
0
votes
1answer
61 views

Is it possible to run Java web application using Nginx server only without tomcat server ?

I am having Java web application (with RESTful webservices). Currently it is running on tomcat server. Is it possible to run Java web application using Nginx server only without tomcat server ??  ...
0
votes
2answers
163 views

known_host for SSH connection

I program an application in Java. This application make a connection between two PC (One Windows and One Linux). My application must make a connection and make few commands. Among commands, I want ...
0
votes
1answer
187 views

SELinux blocks tomcat web application to load Java native library (JNI) - how to configure SELinux on Centos 7?

I have a Centos 7 with Tomcat installed and tomcat user ls -l /var/lib/tomcat total 0 drwxrwxrwx. 5 root tomcat 84 Jul 3 13:18 webapps SELinux is enforcing and a Java web application which tries ...
0
votes
1answer
19 views

Automatic update the file in cloud whenever database of java standalone application is changed

I have created a java standalone application for windows and used SQLite as database and now i want to connect this application with azure so that database can be saved on cloud an anyone help me how ...
0
votes
2answers
384 views

why tomcat7 is using so much RAM?

My Server has only .5GB free memory out of 65GB. total used free shared buffers cached Mem: 64375 63788 587 0 70 11503 -/+...
0
votes
0answers
190 views

Katalon Studio Console Mode fails when started by cron on Linux

I'm using Katalon Studio (https://www.katalon.com/) in Console Mode (https://docs.katalon.com/pages/viewpage.action?pageId=13697253) on Linux (Red Hat Enterprise Linux 7.4) to automate web tests. I'...
0
votes
1answer
47 views

Is it possible to get Apache Kafka to present an SSL intermediate certificate?

After reading this documentation: http://kafka.apache.org/documentation.html#security_ssl I was able to set up Kafka using SSL with a self-signed certificate. I tried setting it up with a Digicert ...
0
votes
0answers
574 views

Jenkins windows slave unable to connect

Trying to start Jenkins slave on Windows with Java Web start gives me this: >java -jar agent.jar -jnlpUrl https://jenkins.example.com/computer/slave-office/slave-agent.jnlp -secret ...
0
votes
0answers
24 views

Running an existing Java project on Google Cloud

I have a Java application I wrote in Eclipse. It takes data from a .txt file, processes it and uses JExcel to write the output into a .xls file. When I run it on my computer, it takes more than 6 ...
0
votes
0answers
74 views

Java web app runs slow only on production server

I have a web app I built that has 1 page that loads very slowly only on my production server (RHEL). My local dev (Windows) and test server (Ubuntu) are no where near as powerful but this particular ...
0
votes
1answer
105 views

tomcat8: 'free(): corrupted unsorted chunks'

We upgraded from Ubuntu 16LTS to Ubuntu 18LTS a couple of days ago and since then have had Apache Tomcat crash completely twice (once per day, about 25 hrs apart). The java process stops running. One ...
0
votes
2answers
221 views

Bind a tcp socket below 1000 with a non root user using Systemd, java and Ubuntu 16.04

I wanted to try socket activation with Systemd and Java on my ubuntu server 16.04. My idea is to make my program able to open directly a standard socket number with a user that is not root. I ...
0
votes
1answer
53 views

How to deliberately fail DNS resolution in Linux to crash-test a Java app?

The situation is rather simple: to reproduce failures which had happened in a recent outage, I'd like to deliberately fail DNS resolution in JVM's in: Caused by: java.net.UnknownHostException: ......
0
votes
2answers
22 views

How to make a Windows Service startup dependent on Java startup?

I have a Windows Service running that is dependent on Java booted up. When I reboot the computer, sometimes Java will take a while to boot up. The Windows Service will attempt to start, but fail since ...
3
votes
1answer
335 views

How do you tell WHY Windows Firewall is blocking a program?

I have an environment that is running Windows Server 2012 R2 and runs a variety of Java based IBM applications. There is a group policy in place that blocks local Windows Firewall rules from being ...
1
vote
0answers
38 views

Root cause for having a number of zero bytes in regular files

We have corrupt files that contain a number of zero bytes. I wonder what the root cause could be. What I know is: All kinds of files that were recently written are affected, they contain a number of ...
0
votes
0answers
83 views

Tomcat 7 server experiencing a sudden (order of magnitude) increase of the Young GC frequency after upgrade of Ubuntu and OpenJDK

What is the issue? After upgrading instances to Ubuntu 16.04 LTS and OpenJDK 8 the GC frequency can, after hours of normal operation, suddenly increase by orders of magnitude ending up using less ...
0
votes
0answers
159 views

metrics collector + Failed to invoke 'unbuffer' + socket connection left open in CLOSE_WAIT state

we have hadoop cluster on redhat machines , while metrics collector installed and running on one of the master machines we see strange warning from the logs , and we cant understand what the meaning ...
0
votes
0answers
141 views

signin issue with AADSTS90002

I am encountering the signin issue with below error. I had created Azure Active Directory insightstest01 and configured as specified in https://azure.microsoft.com/en-in/blog/spring-security-azure-...