Raspberry Pi, NetRexx and JAVA - help for a beginner?
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I have finally fired up my Raspberry Pi (having bought it when it was first released, it has sat on my desk for nearly 2 years awaiting "the right time").
All has gone to plan so far, and I have the latest RASPIAN running. I have download Netrexx and followed the "read.me.first" instructions and the basic Installation Verification Tests have worked. However, I have got into a bit of a muddle.
I consulted the Quickstart Guide (3.02) and it tells me that I should Download the ARMhf JDK and untar it. I followed the links and download the most recent file. Quickstart then instructs me:
tar xvzf ~/jdk-8-ea-b36e-linux-arm-hflt-29_nov_2012.tar.gz (the filename changed)
sudo mv -v ~/jdk1.8.0 /opt/java
What does the -v /opt/java do? I have tried looking at a man page but I cannot track it down, and I do like to understand what chaos I am about to cause.
Re: Raspberry Pi, NetRexx and JAVA - help for a beginner?
I think that if you are using the latest Raspbian image, then you don't need to down load and install the java jdk. To check, you can try running 'dpkg -l *jdk*'. My system responds with:
oracle-java7-jdk 1.7.0+update40 armhf Java™ Platform, Standard Edition 7 Development Kit
You will also find the file 'LICENSE.oracle' in the /boot directory, which is the Oracle license for the jdk.
So any instructions about installing the java jdk are obsolete.
As Bruce correctly says, with the latest Raspbian image there is no need to download Java. If you issue the command 'java -version' it will reply with the java version. Raspbian has a JDK, but even that is not strictly necessary, as any JVM will do, NetRexx does not require a JDK anymore. (If you do not have a JDK, be sure to use the NetRexxF.jar and remember to set the -Dnrx.compiler=ecj property). You know you have a JDK when the 'javac' command works.
I have no clue how the -v /opt/java got into the manual - and that is bad because I probably put it there. As developments have rendered the whole passage obsolete, I have removed it now for the 3.03 edition.