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InetAddress java 8 is not getting the hostname

InetAddress.getLocalHost().getHostName() is no more getting the name of the HostName since I switched to java 8 ...
with the jdk1.8 the InetAddress.getLocalHost().getHostName() returns "localhost". Before (when I was using jdk1.6) it gives me the right hostname (which is "ACTION03") according to the network config :
cat /etc/sysconfig/network
NETWORKING=yes
HOSTNAME=ACTION03
any help ?

There was similar bug fired in JDK.
What I understand is that they changed default resolution process.
They honor configuration in /etc/nsswitch.conf where hosts are configured for /etc/hosts that gives it main priority for name resolution.
Usually /etc/hosts has record for 127.0.0.1 localhost that provide name for host localhost

Works for me on Linux (Ubuntu 14.04) with Java 1.8.0_05.
public class HostName {
public static void main(String[] args) throws Exception {
System.out.println(java.net.InetAddress.getLocalHost().getHostName());
}
}
robert#habanero:~$ javac HostName.java && java HostName
habanero

How to execute a java proram on a Linux machine without a script?

We are using Ubuntu machienes as our servers, such we got 14 servers.
The command ifconfig works on all terminals it gives specific IP address.
When I ran the following java program through a script, on one of the 14 servers I get the host ip as standard 127.0.0.1 (I uploaded this file and script on only 2 machines as of now)
package com;
import java.net.Inet4Address;
public class IpAddressTest {
public static void main(String args[]) throws Exception {
String ipaddress = Inet4Address.getLocalHost().getHostAddress();
String hostname = Inet4Address.getLocalHost().getHostName();
System.out.println("THE IP ADDRESS IS" + ipaddress);
System.out.println("THE HOST NAME IS" + hostname);
}
}
To test this program as which server will give me IP as 127.0.0.1, I need to upload this java class file and related script to execute that on all of the 14 servers.
Is there any other alternate way of finding that? I want to check if i can get the IP THROUGH java , but for this i need to upload these java file and script file to all 14 servers .so asking is there any alternate way 

First, if you want to use Java, then you have to upload the classes and the script to every server.To find all the IP addresses: Get local IP-Address without connecting to the internet

weblogic jmx tomcata php/java bridge and getting t3 protocol working

I have PHP and the PHP/Java bridge set up on Windows and Tomcat 7.0. All is OK there.
However, I am trying to write a php file with java calls to connect to my Weblogic server installed on my Windows 7 machine to play around with adding/deleting users/groups etc.
This is what I followed: http://docs.oracle.com/cd/E13222_01/wls/docs90/jmx/accessWLS.html I also looked at this one http://weblogic-wonders.com/weblogic/2009/10/11/creating-users-in-weblogic-server-embedded-ldap-programatically/ (but for the second one I get an error on the java:comp/env/jmx/runtime line)
However, I cannot get my set up to recognize "t3" protocols to connect to my weblogic. the weird thing is I can connect via a t3 protocol using jython in a separate standalone script and to the console that way.
There is a section in first link above to make sure that wljmxclient.jar is added to the classpath. I set up a classpath to add that. I even use PHP to exec Weblogic's setWLSenv.cmd right before the connection to my Weblogic server is made to set my classpath . . . it shows the jar file in question being added. Still won't work. I then copied the jar file to the JavaBirde/WEB-INF/lib folder. Still wont' work.
I did try IIOP protocol but then I started down an new path of errors where "not bound in this context" was indicated. I tried switching between the 3 Mservers mentioned in the Oracle doc link above. No luck there either.
I see that others have run into this "t3 protocol not supported" message but I don't see any solutions.
Here is my code:
<?php
require_once("java/Java.inc");
$output=exec("C:\Oracle\Middleware\wlserver_12.1\server\bin\setWLSenv.cmd");
$protocol = "t3";
$hostname = "localhost";
$port="7001";
$jndiroot="/jndi/";
$mserver="weblogic.management.mbeanservers.domainruntime";
$united = $jndiroot.$mserver;
$serviceURL = new java("javax.management.remote.JMXServiceURL",$protocol, $hostname, $port,$united);
$h = new java("java.util.Hashtable");
$h->put("javax.naming.Context.SECURITY_PRINCIPAL", "myUID");
$h->put("javax.naming.Context.SECURITY_CREDENTIALS", "myPWD");
$h->put("javax.management.remote.JMXConnectorFactory.PROTOCOL_PROVIDER_PACKAGES",
"weblogic.management.remote");
$connector = new java("javax.management.remote.JMXConnectorFactory");
$connector->connect($serviceURL,$h);
?>

This is how I FINALLY connected to my Weblogic:
1) I installed Tomcat 7.0 zip file instead of the installer and set it up manually. In my
setenv.bat file it looks like:
set CATALINA_HOME=C:\Program Files (x86)\Apache Software Foundation\apache-tomcat-7.0.34
set CATALINA_BASE=C:\Program Files (x86)\Apache Software Foundation\apache-tomcat-7.0.34
set JAVA_HOME=C:\Program Files (x86)\Java\jdk1.7.0_09
set JRE_HOME=C:\Program Files (x86)\Java\jdk1.7.0_09\jre
set JAVA_OPTS=-Djava.ext.dirs=C:\Oracle\Middleware\wlserver_12.1\server\lib
set CLASSPATH=.;C:\Oracle\Middleware\wlserver_12.1\server\lib\wljmxclient.jar
exit /b 0
2) I enabled IIOP protocol in weblogic through the weblogic console and added a userid/password which I used in num 3 for the userID/password
3) My php script on Tomcat 7 with the PHP/Java Bridge (not the JMXServerURL . . . nowhere did I find that you had to use "rmi" as the protocol")
$serviceURL = new java("javax.management.remote.JMXServiceURL","rmi","localhost","7001","/jndi/iiop://localhost:7001/weblogic.management.mbeanservers.edit");
//"service:jmx:iiop://localhost:7001/jndi/weblogic.management.mbeanservers.edit");
$env = new java("java.util.Hashtable");
$env->put("javax.management.remote.JMXConnectorFactory.PROTOCOL_PROVIDER_PACKAGES","weblogic.management.remote");
$env->put("javax.naming.Context.SECURITY_PRINCIPAL", "myuserID");
$env->put("javax.naming.Context.SECURITY_CREDENTIALS", "mypassword");
$jmxCon = java("javax.management.remote.JMXConnectorFactory")->newJMXConnector($serviceURL, $env);
$jmxCon->connect();
$connection = $jmxCon->getMBeanServerConnection();
$mbeans = $connection->queryNames(null,null);
foreach($mbeans as $key=>$value) {
echo $key. "=". $value;
}
It connected and printed out all the mbeans for my admin server and my two managed servers that I created for testing.

Java RXTXcomm lib to connect to /dev/ttyACM0

I'm using RXXTX java lib to connect to serial ports. I'm using this lib with no problems connecting to /dev/ttyUSB0 (1,2,3,etc).
But when I want to connect to /dev/ttyACM0 the port its not found.
CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier("/dev/ttyACM0");
the Exception is thrown:
gnu.io.NoSuchPortException
at gnu.io.CommPortIdentifier.getPortIdentifier(CommPortIdentifier.java:218)
I already listed all the ports but no success.

Processing and USB ports /dev/ttyACM0, /dev/ttyACM1, ....
http://pblog.ebaker.me.uk/2011/09/processing-usb-ports-devttyacm0.html
Processing doesn't like reading Linux USB devices like /dev/ttyACM0 or
/dev/ttyACM1.
The solution is easy, just symlink the devices like this...
ln -s /dev/ttyACM[x] /dev/ttyS8[x]
You can put any number after the ttyS, although it is possible that
ttyS0 and other low numbers are defined, numbers in the eighties are
(almost) guaranteed to work.

This might help you: https://groups.google.com/forum/#!topic/openhab/f-gVkwJg-hg
update your startup script to include "->Dgnu.io.rxtx.SerialPorts=/dev/ttyACM0" in the Java command line

Possible causes can be invoking https when the application is not configured for security

I create web service
#WebService(serviceName = "DynamipsService2")
#Stateless()
public class DynamipsService2 {
#WebMethod(operationName = "StartSession")
public static String StartSession(#WebParam(name = "key") String key) {
try {
return "100-Session started";
} catch (Exception ex) {
return null;
}
}
}
I want to test but on the page
http://localhost:8080/DynamipsService2/DynamipsService2?Tester crash bug
Error generating artifacts for the
following WSDL
http://localhost:8080/DynamipsService2/DynamipsService2?WSDL
Possible causes can be invoking https
when the application is not configured
for security
I created other Web services in the same assembly and it works.

I just experienced this problem as well. The solution for me was to use my hostname rather than localhost in the URL for the Tester.
So in my case, the following, which is what NetBeans/Glassfish did by default when I clicked Test Web Service in the NetBeans UI, did not work:
http://localhost:8080/Calculator/Calculator?Tester
However, when I paste the following into a browser, it does work:
http://david-pc:8080/Calculator/Calculator?Tester
I couldn't figure out how to change the hostname that NetBeans uses for the built-in Test dialog (nor could I cut+paste the URL from the error dialog). So I had to visually copy the URL from the error message into a browser, replacing the hostname along the way.

I had the same problem and the reason apeared in the Server's log. I'm useing Glassfish 3.1 with netBeans 7. And the error I got in the Glassfish output was:
INFO: [ERROR] com.sun.tools.javac.Main is not available in the classpath, requires Suns JDK version 5.0 or latter.
I googled a bit and it appeared to be because the glassfish server was working with the openjdk that came with ubuntu. If your problem is the same the solution I found was to remove the openjdk jre, like this:
sudo apt-get remove openjdk-6-jre
sudo apt-get autoremove
Hope this is useful.
PS: I assigned /usr/lib/jvm/java-6-sun/bin/java in the java tab at the servers configuration wizard in netBeans but don't know if that was part of the solution (I'm afraid to change it back :p)

I had the same problem with Glassfish
but it was more compilcated because of the NAT
I have GF in NAT - do MYDOMAIN and port is redirected to internal machine
the problem in GF is that it tries to connect to itself by the domain name which again redirects to inside network
(the ?wsdl works properly)
I have made temp solution adding to /etc/hosts (127.0.0.1 domainname)
be aware that it's only a temp solution
try to check if you have "localhost" in your hosts file (in windows c:/windows/system32/drivers/etc/hosts )
and ping localhost
I will add GF log - maybe someone in future will search it by google :) :)
moreover I looked GF logs there was something like ->
Connection timed out
Failed to read the WSDL document: http://MYDOMAIN:8080/MYSERVICE?WSDL, because 1) could not find the document; /2) the document could not be read; 3) the root element of the document is not <wsdl:definitions>.
failed.noservice=Could not find wsdl:service in the provided WSDL(s):
At least one WSDL with at least one service definition needs to be provided.
Failed to parse the WSDL.

Which web server do you use? If you use glassfish you can open server admin page and select Configurations===>server-config===>Security
and make Security Manager enabled

Check your domains/{YOUR_DOMAIN}/config/domain.xml
If you setup Glassfish using Eclipse, all will be done for you automatically.
Now I am surprised if I start the domain from the command line, it gave me that error, but starting Glassfish 4 from Eclipse, it is not showing any problem.

One cause could be that you don't have correctly configured the environment variable JAVA_HOME (with the correct path) and the JAVA_HOME/bin directory added to global PATH environment variable as well. For some processes the glassfish look for the classpath of the JDK installed.
Hope this help.

I had the exact same problem and it is because you have a static method, I realised after debugging for some while. Just remove static from the method and it should work.
#WebMethod(operationName = "StartSession")
public String StartSession(#WebParam(name = "key") String key) {
try {
return "100-Session started";
} catch (Exception ex) {
return null;
}
}