Every now and then I need to get the list of collections in a SOLR cloud instance from a Java program. The docs seemed opaque on how to do it, so:
CollectionAdminResponse response = new CollectionAdminRequest.List().process(server);
ArrayList
I frequently start a git project without a .gitignore or often add entries to a .gitignore later. And then I have to update the repository to remove entries that match those entries. Here's the sequence I use:
git rm -r --cached .and then
git add .git commit -m "..."git push...
Occasionally, and especially during the debugging phase of a development effort, I like to be able to create a message that appears in the web page on which I'm working, one that disappears after a few seconds. A flash message.
In the past, I've accomplished this in a variety of ways, including timeouts and so on. And some frameworks (Tapestry, e.g.) provide this kind of thing from the server as a built-in mechanism. But I'm just interested in doing this from within javascript.
Anyway, I was recently fooling around with prototypes and extending the javascript String object, and it occurred to me that a String extension to flash a message would be trivial to do, epsecially with JQuery to handle the timing parts. So I wrote this:
String.prototype.flash = function(){Coupled with a
$(".flash").html(this).fadeIn("fast");
setTimeout(function(){
$(".flash").fadeOut("slow");
}, 3500);
}
I am able to write flash messages off typical JS Strings:
("This is COOOOOL...").flash();Which will show that message inside the DIV, then get rid of it after 3.5 seconds. I could extend it to parameterize the time and even the fade effects. But sometimes simpler is bester.
Using the MessageDigest Class, here's code to create an MD5 Hash of a String:
File it under "another thing I need to do a lot"... Some kind of caching of java objects.
Turns out there is a neat cache library from google called Guava that's very easy to inject into Spring and easy to configure and access.
The Spring beans look like this:
<bean id="cacheBuilderSpec"
class="com.google.common.cache.CacheBuilderSpec"
factory-method="parse"
c:cacheBuilderSpecification="${cacheSpecification}" />
<bean id="cacheBuilderFromSpec"
class="com.google.common.cache.CacheBuilder"
factory-method="from"
c:spec-ref="cacheBuilderSpec" />
<bean id="cache"
factory-bean="cacheBuilderFromSpec"
factory-method="build" />
Dumb Windows Things annoy me, which means I'm annoyed a lot :-)
One thing is that opening Windows Explorer always opens to the user's "home" directory. As a developer, that's almost always the last place I want to be. What I really want is to have a shortcut that opens Windows Explorer on a specific folder, or on the root of my C: drive.
Turns out, this is trivially easy. Open properties on the link and add the folder to the end of the "Target":
%windir%\explorer.exe C:
Voila...
I have a Dell XPS laptop running Windows 7. Recently, MS pushed out an update which, for some reason, never really completed - I was left with a message about Windows shutting down after the upgrade was complete. I had left the machine on to perform the upgrade overnight, so it was a surprise to see this the next morning.
Well, not figuring out anything else to do, I pushed the power off button and then again to restart the laptop. Every time I did this, I would end up at the same place - with the message that Windows would restart after is was complete. I tried to get into safe startup mode (F8), but that never worked. I was getting a little concerned and called an IT guy to help.
He suggested that when I power off the laptop, I hold the power button down and not just press it. Well, that worked fine. I should have realized it, but simply pressing the power button puts the laptop in sleep or hibernate mode and then pressing it again starts back where it was left off. I knew how this worked in normal operations, but was surprised (though shouldn't have been?) to find the same during an update. So - lesson learned...
Weirdest thing happened. After starting my laptop (Dell XPS 17, Windows 7), I had no internet connectivity. The network connections were fine - I could see other machines on my domain, but no connect out to the internet. My laptop is set up with an external monitor (LG Electronics 34UM94-P 34-Inch LCD - waaay cool!), mouse and keyboard. And the keyboard and mouse are USB connected to the monitor, which in turn is connected to the XPS laptop.
Did a bunch of poking around for possibilities. In the end, what worked was shutting down the laptop, unplugging the USB and the monitor, and then restarting the laptop. It came up fine, with full network and internet access. Then plugged in the monitor - still had internet; and then the USB. Internet and network access was fine and the keyboard and mouse worked.
Don't know why, but recording this for posterity!
I create Virtual Box Virtual Machines for just about every project, so I end up installing Java on them a lot. I like the Oracle JDK, but for licensing reasons, that install is not available as part of the "normal" apt repository.
I installed Java via a PPA (http://askubuntu.com/questions/4983/what-are-ppas-and-how-do-i-use-them) by webupd8team (http://www.webupd8.org/2012/01/install-oracle-java-jdk-7-in-ubuntu-via.html). I ran these commands to add the PPA to the apt-get repo and update that repo, install Java7, and set up the various java 7 environment variables.
add-apt-repository ppa:webupd8team/java
apt-get update
apt-get install oracle-java7-installerapt-get install oracle-java7-set-default
I switched over to an SSD to replace the HDDs on my Dell XPS laptop. What a speed improvement. And, this is way too easy.
I was a little nervous about going to an SSD for everything - I had read that there are limits to the number of write operations an SSD can support before failure. But a little online reading put my mind at ease - mostly the thinking that on a 3 year old laptop, the computer itself will be out of date before the SSD fails. The laptop is an XPS 17. It has an I7 quad code CPU, 16GB of RAM, and dual 750GB HDD drives. So I went ahead.
I ordered a Samsung 850 1TB SSD from Amazon (http://www.amazon.com/gp/product/B00LF10KTE/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1). When it arrived, I also realized it did not come with a USB cable, so I ordered that next (http://www.amazon.com/gp/product/B00HJZJI84/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1).
Once I had both, I installed the Samsung migration tool that came with the SSD and ran the clone from my C: drive to the new SSD. It took about 3 hours to clone about 650GB. Word to the wise: make sure nothing else besides the migration tool is running or the clone might be incomplete.
After that was complete, I shut down the laptop, unscrewed that back panel and removed the #1 HDD. Then plugged in the SSD and screwed it in. It all fit perfectly. I booted the laptop, also no problems. And boot time was remarkably quick.
And that's it. I am thrilled with the speed.
Often, especially with large file transfers, it seems that the shared folders facility in VirtualBox (running Ubuntu, but not sure that matters), running as a Windows guest, are very slow.
I added these lines
255.255.255.255 VBOXSVR #PRE 255.255.255.255 VBOXSRV #PRE
I recently upgraded my VirtualBox Guest Editions to 4.3.10 and the shared mounts that I normally create stopped working. I was running this mount:
sudo mount -t vboxsf Dropbox /home/steve/DropboxAnd getting this error:
mount: wrong fs type, bad option, bad superblock on /home/steve/Dropbox,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail ...
cd /sbinThis did the trick. Thanks to this post for the tip:
sudo rm mount.vboxsf
sudo ln /usr/lib/x86_64-linux-gnu/VBoxGuestAdditions/mount.vboxsf mount.vboxsf
I wrote about building a Java-based development stack using Ubuntu on a VirtualBox VM some time back (http://www.tractare.blogspot.com/2011/10/ubuntuvirtualboxjava-team-development.html, and http://www.tractare.blogspot.com/2011/10/ubuntuvirtualboxjava-team-development_04.html). But that was a couple of years ago and the technology has changed, so this is a rewrite. Also, that version didn't include Marklogic, which is a part of the stack for this particular application. So here's the stack I'm building out and the steps I took to get there.
First off, I'm building this in Virtual Box 4.3.8, installed on a Dell XPS laptop quad-code I7, 16GB RAM and dual 750GB HDD running Windows 7. Second, some of these kits I installed using PPAs, so if you have security concerns about PPAs, you'll need to find other ways for those tools.
The development stack I'm installing is this:
add-apt-repository ppa:webupd8team/java apt-get update apt-get install oracle-java7-installerapt-get install oracle-java7-set-default
tar -zxvf eclipse-...
sudo cp -r eclipse /opt
cd /usr/local/bin
cp -r /opt/eclipse/eclipse eclipse
After that, I ran eclipse from the command line and then pinned it to the launcher.One issue I had with Eclipse was that the command menus didn't work. I had to edit the eclipse.desktop file in ~/.local/share/applications to get it to work by commenting out the Exec and adding this one:Exec=env UBUNTU_MENUPROXY=/usr/local/bin/eclipse
Downloaded Marklogic7 for 64Bit RedHat Linix and ran these commands apt-get install alien alien --to-deb --verbose MarkLogic-4.1-6.x86_64.rpm dpkg -i marklogic_4.1-6_amd64.deb /etc/init.d/MarkLogic start The one issue I had with the ML install is that the Marklogic script in /etc/init.d runs under /bin/sh and Ubuntu's default shell is bash. So I changed the first line of that script to #!/bin/bash
I do a lot of development of web applications in VirtualBox virtual machines running Ubuntu. Although I could (and sometimes do) set up the virtual machine to have multiple monitors, I usually don't, instead leaving one monitor for the host OS (Win7) and another for the VM. So it's handy for me to be able to run a browser on the host OS and access a web application on the VM. In VirtualBox, I accomplish this with Port Forwarding.
Go into settings for the VM and select Network->Advanced and click Port Forwarding.
Then enter the IP address of your host machine, the port to forward, the IP address of the guest and the port the web application runs on.The example below sets up forwarding from http://localhost:8080 to a web application running on port 8080 (Tomcat in this case) on the VM:
UPDATE: after going through all of this, the OS locked up on me. I had to hard-stop it and then could notrestart - VirtualBox couldn't find the boot disk. So I'm going back to Ubuntu. I don't know why this happened, but I don't have time to explore it either...
I've gotten in the habit of created Ubuntu virtual machines on my laptop for various projects. I have a new one starting up and decided to create a new VM for that. I was going to install Ubuntu, but I recently heard about the Mint OS. Kind of an Ubuntu clone with a different desktop - Cinnamon instead of Unity. Since Unity isn't my favorite part of Ubuntu, I thought I'd give mint a try. So here's the blow-by-blow.
I have a Dell XPS I7 quad-core with 16Gb RAM and 2x750GB HDDs. The hardware is a beast. It's running Win7. I use Oracle VirtualBox to create the VMs.
I downloaded the 64 bit ISO of the Cinnamon version of mint from http://www.linuxmint.com/
I already have VirtualBox installed, so I started out by creating a new VM in VirtualBox. I specified a 64bit Ubuntu system with 10gb RAM and an 80GB hard drive. In settings I put the following:
