TOPIC: INTEGRATED DEVELOPMENT ENVIRONMENT
Getting Eclipse to start without incompatibility errors on Linux Mint 19.1
12th June 2019Recent curiosity about Java programming and Groovy scripting got me trying to start up the Eclipse IDE that I had installed on my main machine. What I got instead of a successful application startup was a message that included the following:
!MESSAGE Exception launching the Eclipse Platform:
!STACK
java.lang.ClassNotFoundException: org.eclipse.core.runtime.adaptor.EclipseStarter
at java.base/java.net.URLClassLoader.findClass(URLClassLoader.java:466)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:566)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:499)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:626)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584)
at org.eclipse.equinox.launcher.Main.run(Main.java:1438)
at org.eclipse.equinox.launcher.Main.main(Main.java:1414)
The cause was a mismatch between Eclipse and the installed version of Java that it needed to run. After all, the software itself is written in the Java language and the installed version from the usual software repositories was too old for Java 11. The solution turned out to be installing a newer version as a Snap (Ubuntu's answer to Flatpak). The following command did the needful since snapd already was running on my machine:
sudo snap install eclipse --classic
The only part of the command that warrants extra comment is the --classic switch, since that is needed for a tool like Eclipse that needs to access a host file system. On executing, the software was downloaded from Snapcraft and then installed within its own bundle of dependencies. The latter adds a certain detachment from the underlying Linux installation and ensures that no messages appear because of incompatibilities like the one near the start of this post.
A look at Emacs
10th August 2010It's remarkable what work can bring your way in terms of technology. For me, (GNU) Emacs Has proved to be such a thing recently. It may have been around since 1975, long before my adventures in computing ever started, in fact, but I am asking myself why I never really have used it much. There are vague recollections of my being aware of its existence in the early days of my using UNIX over a decade ago. Was it a shortcut card with loads of seemingly esoteric keyboard shortcuts and commands that put me off it back then? The truth may have been that I got bedazzled with the world of Microsoft Windows instead, and so began a distraction that lingered until very recently. As unlikely as it looks now, Word and Office would have been part of the allure of what some consider as the dark side these days. O how OpenOffice.org and their ilk have changed that state of affairs...
The unfortunate part of the Emacs story might be that its innovations were never taken up as conventions by mainstream computing. If its counterparts elsewhere used the same keyboard shortcuts, it would feel like learning such an unfamiliar tool. Still, it's not as if there isn't logic behind it because it will work both in a terminal session (where I may have met it for the first time) and a desktop application GUI. The latter is the easier to learn, and the menus list equivalent keyboard shortcuts for many of their entries, too. For a fuller experience though, I can recommend the online manual, and you can buy it in paper form too if you prefer.
One thing that I discovered recently is that external factors can sour the impressions of a piece of software. For instance, I was using a UNIX session where the keyboard mapping wasn't optimal. There's nothing like an unfamiliar behaviour for throwing you off track because you feel that your usual habits are being obstructed. For instance, finding that a Backspace key is behaving like a Delete one is such an obstruction. It wasn't the fault of Emacs, and I have found that using Ctrl+K (C-k in the documentation) to delete whole lines is invaluable.
Apart from keyboard mapping niggles, Emacs has to be respected as a powerful piece of software in its own right. It may not have the syntax highlighting capabilities of some, like gedit or NEdit for instance, but I have a hunch that a spot of Lisp programming would address that need. What you get instead is support for version control systems like RCS or CVS, along with integration with GDB for debugging programs written in a number of languages. Then, there are features like file management, email handling, newsgroup browsing, a calendar and a calculator that make you wonder if they tried to turn a text editor into something like an operating system. With Google trying to use Chrome as the basis of one, it almost feels as is Emacs was ahead of its time, though that may have been more due to its needing to work within a UNIX shell in those far-off pre-GUI days. It really is saying something that it has stood the test of time when so much has fallen by the wayside. Like Vi, it looks as if the esteemable piece of software is showing no signs of going away just yet. Maybe it was well-designed in the beginning, and the thing certainly seems more than a text editor with its extras. Well, it has to offer a good reason for making its way into Linux too...
If all else fails...
3rd June 2010
Two problems have come my way that were resolved by removing configuration files and going again. Both affected Linux installations that I have. The Ubuntu installation on my main PC is working well, but I ran into trouble starting up NetBeans 6.8. No GUI would ever appear but taking away the .netbeans folder from my home area allowed a fresh start with the IDE starting up as it should. To date, not all the various projects that I have are restored, but that can be done as I go along. Plugins for PHP development needing reinstatement, but that was another easy thing to achieve; just go to Tools > Plugins on the menus and work with the dialogue box that appears to download and install the needful.
The inspiration for taking the configuration folder from the home area came from needing to address a misadventure with a Debian VM. Perhaps foolishly, I went using gconf-editor on there and messed up the appearance of the terminal window with whatever change I made. Getting rid of the .gconf folder restored order with its recreation by the system. Next time, remembering what changes have been made and reversing them might be the best course of action...
A reasonable requirement of an IDE
20th May 2008I have been having a play with NetBeans IDE Early Access for PHP and, while it has a lot to offer, one impression remains uppermost in my mind: it is so slow. While I might have a project with many files in it, start-up takes an age because of project checking. Other functionality such as text searching is far from speedy either. The sluggishness probably arises from this release being very early in its life cycle, and it reminds me of how slow older versions of the Java IDE were, even if this is slower. For PHP development, I'll be giving NetBeans a while to mature before taking another look at it.
On a similar note, I recently dispatched Quanta Plus from my system for sluggish start-ups and will not return to it because other alternatives such as Bluefish and Eclipse PDT fit my needs much better. I like my editors to be slick and responsive, and Quanta has been around long enough for any slowness to be knocked out of it. However, I get the feeling that the extras have added bloat, while I expect any additional functionality that I never use not to get in my way. It is for the latter reason that I was always able to get on with Dreamweaver and even run it on Ubuntu using the WINE library. If I really wanted a stripped out yet functional editor, Gedit would do most of what I need - it colour-codes syntax for a variety of languages for a start - but it's always handy to have a file system explorer window incorporated and I value any syntax checking and auto-completion as well. So, it looks as if Eclipse and Bluefish could be serving my needs for a while to come, alongside so use Dreamweaver for online editing of website files.