Unhandled exception when running sample program SystemInfoExample about pi4j-v1 HOT 9 CLOSED

Additional info for my RPi:

pi@mypi ~/workspace/SystemInfoExample $ hostname --all-fqdns

pi@mypi ~/workspace/SystemInfoExample $ hostname -a

pi@mypi ~/workspace/SystemInfoExample $ hostname -A

pi@mypi ~/workspace/SystemInfoExample $ hostname -d
pi@mypi ~/workspace/SystemInfoExample $ hostname -f
mypi
pi@mypi ~/workspace/SystemInfoExample $ hostname -i
127.0.1.1
pi@mypi ~/workspace/SystemInfoExample $ hostname -I
192.168.20.140
pi@mypi ~/workspace/SystemInfoExample $ hostname -s
mypi
pi@mypi ~/workspace/SystemInfoExample $ hostname -y
hostname: Local domain name not set
pi@mypi ~/workspace/SystemInfoExample $

from pi4j-v1.

same error "hostname --all-fqdns" returns nothing on my raspberry

from pi4j-v1.

I will look into this issue next week. Thank you for the defect report.

from pi4j-v1.

I've looked into this a bit more including studying the source code. I think the code is a bit eager to throw exceptions in places where it shouldn't. I see that you capture info in the form of key/value pairs, and if either a key or value is absent/invalid or blank, you throw an exception. In the context of program design, you require the caller to do some exception handling, and the implementation as it is now requires that the calling code is more complex than the called code. User code handling a possibly blank return value would have to add try/catch logic and translate an exception back to a blank value. This is a minor design problem.

I would suggest that instead of throwing an exception for missing/invalid or blank key or value, that you instead return a blank string, which is actually closer to (or exactly) what the answer should be.

from pi4j-v1.

The new 0.0.4-SNAPSHOT build is available for testing. This build includes changes to allow for empty/null NetworkInfo properties returned by the "hostname" command.

You can download it from the Maven repository here:
https://oss.sonatype.org/content/groups/public/com/pi4j/pi4j-core/0.0.4-SNAPSHOT/

Please report success or any remaining open defects/issues.

from pi4j-v1.

I am unfortunately running the Debian wheezy build (2012-08-08-wheezy-armel) which seems to have an older java than what you built for the 0.0.4 snapshot (the 0.0.3 jar file worked fine). I have attempted to bring it up to date with "sudo apt-get update" and "sudo apt-get upgrade" but the error remains. Without all the blah blah I get:

root@mypi:/home/pi/workspace/SystemInfoExample# javac -cp pi4j-core-0.0.4-20121120.062224-1.jar -d . SystemInfoExample.java
warning: pi4j-core-0.0.4-20121120.062224-1.jar(com/pi4j/system/NetworkInfo.class): major version 51 is newer than 50, the highest major version supported by this compiler.
It is recommended that the compiler be upgraded.
warning: pi4j-core-0.0.4-20121120.062224-1.jar(com/pi4j/system/SystemInfo.class): major version 51 is newer than 50, the highest major version supported by this compiler.
It is recommended that the compiler be upgraded.
2 warnings
root@mypi:/home/pi/workspace/SystemInfoExample#
root@mypi:/home/pi/workspace/SystemInfoExample#

root@mypi:/home/pi/workspace/SystemInfoExample# sudo java -classpath .:pi4j-core-0.0.4-20121120.062224-1.jar com.pi4j.example.SystemInfoExample

HARDWARE INFO

Exception in thread "main" java.lang.UnsupportedClassVersionError: com/pi4j/system/SystemInfo : Unsupported major.minor version 51.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:634)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:277)
at java.net.URLClassLoader.access$000(URLClassLoader.java:73)
at java.net.URLClassLoader$1.run(URLClassLoader.java:212)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
at java.lang.ClassLoader.loadClass(ClassLoader.java:321)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)
at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
at com.pi4j.example.SystemInfoExample.main(SystemInfoExample.java:51)
root@mypi:/home/pi/workspace/SystemInfoExample#

I visually inspected your code changes and the code base seems to be okay but I can't verify with what currently I have on my pi.

[Sent from ice weasel on my pi. :-) ]

from pi4j-v1.

On the Debian (armel) distribution, I am running the Oracle JDK 7u6 which is much faster than the OpenJDK.
http://www.savagehomeautomation.com/projects/raspberry-pi-installing-oracle-java-development-kit-jdk-170u.html

from pi4j-v1.

I have now updated to Oracle JDK 1.7.0_06 and the code works fine (fix verified).

Thanks for all of your hard work!

from pi4j-v1.

Thank you for testing it out. Issue closed. Fixed in 0.0.4-SNAPSHOT

from pi4j-v1.