I like your last paragraph. That's very accurate with what I would call the real world of Admin. If you are spending a significant amount of your time worrying about who to blame when it goes wrong, then you sure aren't doing much work yourself. Accountability is BS, when it's not working, the Admin is always held accountable, because that's what they are paid to do. If you can't install/configure the software running on your servers, then you aren't qualified for your job. I'm paid to make things work, not to point fingers at other people when it doesn't. I run Debian because in the many years that I have, it has never let me down. The only downtime I've had was from a kernel compile issue, and that was my fault. Well... there has been other downtimes, but they've been from third parties installing firewalls without allowing my machines through, which were quick enough to fix, but I was the one that everyone looked to for the solution, not the support of some third party that are taking support fees.
There are plenty of good business reasons to want to use Debian... the very same reasons you or I use it.
1) Security updates are done quicker than recompiling/manually installing (The competition is catching up).
2) Software installation to a new machine will take less time on a Debian system because it will update to the latest versions automatically instead of applying patches over the original install (competition is catching up).
3) More software packages prepackaged means that there are fewer custom compilations/installs, which means installing/upgrading client machines will take less time.
4) Setting up your own APT server means you can distribute your own upgrades internally, and even package non-standard software yourself. This means you can write one install/setup/upgrade script for oracle, and have it automatically propogate through the network instead of installing it on a per machine basis.
Every one of these points saves time. If a company is under pressure right now to save money, applying some of that presure on IBM might be a good way to get the ball rolling toward getting support for Debian. IBM only supports SuSE and RedHat because that's what everyone else uses. There is enough room in the market for another supported distro, especially one as easy to support as Debian.
I wouldn't sacrifice support, because that would put your job on the line, but I would lobby them to ask IBM to support Debian. If enough people in your position do, they'll add it to the supported list. You might want to have them run a test on the next server upgrade/install by installing Debian on it. If that means that IBM doesn't get service fees for that server, and you tell them so, then they'll start paying attention. You're company can always switch a single, not-so-critical system to a supported platform at any time without a significant loss. You just have to convince them that the potential economical gains are significant enough. If that server sits in the corner doing it's job without anyone touching, they'll start to see the wisdom. If you suggest something like a single server as a test bed, they'll see it as more of an experiment to try to save money, and if it fails, it probably won't be your job, but if it succeeds, and you implement it company wide and save a lot of money, then you will probably have eliminated a need for your job, and your boss will get a raise from the portion of your no longer needed salary.:)
Good, good... I like your logic. What you're trying to say is that even though company X offers what the people want for about the same prices, people will stick with Verizon who tells customers what they want. Last time I checked, consumers drove the market, not the other way around. All the other reasons you mention are fine if no one else is offering the service that the customer wants, but that clearly isn't the case, now is it?
Most of the power used by LCD is still going to be the backlight. The LCD itself doesn't even get warm itself. You may loose a few few minutes of battery life, who knows.
I like to use the time tested Hole(TM) technology of keeping things safe. The oldest data in existance is a well preserved beastiality pornography collection stored on the wall of a cave.
The government has been using it for years to store information for both security and safety reasons. In fact, I bet your dog uses the very same technology for storing his snacks.
Also see the "Don't put all your eggs in one basket" technology.
It's already been mathematically proven that capitalism is not the most effecient economy. The extent of government's involvement should be limited to keeping the playing field level and trying to ensure the public's interests as a whole (where capitalism breaks down... AKA the free-loader problem).
You actually imply that capitalism isn't a part of government.
Capitalism is a form of economy where anything goes (economically). This is bad because when "anything goes"/"lassez faire" economic principals are applied, it means that any given company will do anything within law to destroy competition. The reason why capitalism works at all is that competition exists. If you were forced to buy your food from only one company, then you would really be screwed, because they could charge anything they wanted. If you draw the supply and demand curves, you would see that they optimize in a position where some people will die. It is possible for capitalism to reach such a place in "lassez faire" (some people call this "pure") capitalism. This is basically what Microsoft has on the small businesses of the world, and no doubt, some of them have gone under due to expenses of overly priced software. This is bad for the market as a whole.
So, my point is that capitalism as a whole is so bad that it requires government involvement, but because we are capitalistic, the government can be bought easier than the competition. You're not going to find people getting elected if they don't support enough big-money special-interest agendas in order to get funded.
Corperations, as we know them today, were tacked onto capitalism. There's just too many rights for a company. Lobeying is nothing more than buying votes. If employees could afford to do so, they could afford lower wages. Because of the falure of corperations to work properly, we had unions crop up to be the other great evil. So because of lobeying and stupid special interests, we now have a special interest government where the government represents a million special interest groups instead of the population as a whole.
I know that every fax machine is compatible with every other one for a reason, because the spec is good enough. It's just data over a 9600 or 19200 baud stream that's been converted in the standard way to an audible sound. There are data and fax tones, and it's not unreasonable to require them in order for your fax machine to work properly.
You would think for compatibility sake the telcos would have devices to detect digital and just use modems (in the real definition, not the device) to forward the digital signals through, or even better, someone create Fax over IP.
The price of a telephone and internet connection is about as much as my SprintPCS, but I get free long distance, all calls after 7 or on the weekend, and unlimited internet at rates at least a little better than a 56K modem. Oh yeah, and I could hook it up to a laptop just about anywhere in town (and along every interstate) and post to slashdot.:)/. responsibly... don't/. and drive.
Well, under Windows and Mac OS X, you don't need scripts. Under Linux you need them for Executable Jar format because in order to make linux run an executable jar, there are about 8 pages of instructions to do on every machine to make it work. It's not a failing with Java, but a snobbish attitude of distros, which hopefully with Kaffe, etc. that attitude will change. You can just double click jar files on every other platform. Linux's idea of a launcher forces you to use a shell script, even for perl and python, and it forces you to modify your file to support Linux instead of the more proper way of the OS supporting the program. Don't ever write a scripting language where # isn't a comment, else you'll be just as screwed.
If it were done right, all files would have a mime type attribute, and user specific table would specify how to run a file with that mime type.
There is a Java WebStart implementation for Linux that works great.
If you want to refer to a directory of jars, you need to use the boot class path parameter to the VM.
Most people, however, will either use a manifest file: manifest.mf: Class-Path: main.jar lib/library.jar lib/otherlib.jar Main-Class: org.slashdot.example.MainClass
(Don't for get the blank line at the end).
And/Or they will use WebStart, where you declare what you need in XML, and it can be launched and is automatically updated through the internet when available.
All this is free of course, and so is Ant, which you can use to automatically compile and build your directory structure, including your executable jar file and any libraries you need.
If you have a hard time running a Java application, it's the developers fault. There are PLENTY of ways to make it easy... easier than installing software on any other system.
I know a lot of people run Trillian, GAIM, etc. as well.
My only point is to say that it's not either/or. If google pushes underpants, I would try them. If enough people give it a try, and they have enough cool features like GMail, they will stay. Searching your old IM's is a nice way to start.
So... I think there's always room for one more IM protocol. The only reason AIM is big is because Grandma uses AOL, and thinks that AIM is IM. I think grandma knows how to google too.:)
I'm much too lazy to go look up the specs and calculate everything out, but I'll sure Google for it:)
http://www.benchtest.com/gp_Temp4.html is a guy doing just this.
You need to know how to do your resistor calculations from basic electronics/physics. Thermistors have a temperature range and a corresponding resistance range. You have to calibrate it yourself and you'll probably have to put in something to help with the logarythmic nature of the themistor.
http://www.eidusa.com/Electronics_Kits_EUSB_To_1 _T HR.htm has some information and formulas for calibration.
Want to control external devices from your computer? I suggest getting a serial servo controller because they are fun. If you want to just turn something on and off, it's a bit overkill to put a servo to actually flip a switch, but it's still really fun.:)
If you really want to do it the right way: Get X10 if you use a space heater/wall AC... you may have to still use a really big relay to handle the draw. Don't forget to check the maximum capacity of your electronics. Use the parallel port to trigger a relay and run the connection wires to the mercury switches in your normal thermometer.
Also, you can put in photo-resistor/transistors to measure light level, and use X10 to control your lighting level of a room. You could get a motion detector and hook it up to your joystick port's buttons, but you'll have to disect the motion sensor.
You can set up trip alarms pretty easy with infrared emitters and detectors.
Video for Linux is cool enough that you can get a cheap X10 Cam and write simple algorithms to do neat stuff.
I've actually helped build a system that used an FM reciever piped to voice recoginition software that the guy could turn his lights on from outside just by saying the right word. We also set up a servo controlled robotic arm with a laser pointer and a web-cam. The site let you click on the picture and it would point the laser at that point.
I'm really not impressed with web-enabled appliances. It would be much more useful if the appliances were more aware of what was going on. One of the coolest, useful wacky ideas that I've seen is the Java toaster that burned the forcast into toast. (http://www.theregister.co.uk/2001/06/04/bread_as_ a_display_device/)
There was talk of making a device for market that let people advertise on toast, IIRC.
Finally... another neat way to make your computer do cool stuff is to get a cheap atmel chip, hook it up to your serial port, and program it to do whatever you want. You can hook up better I2C sensors pretty easily then too. Some of those have exact ranges precalibrated and they are accurate to 10bit.
Well... I've run out of cool ideas for you to play with... just search on google and you'll find a ton of hobbiest out there ready to share all the information you need to hook anything you want up to your computer.
>> The screens are too small for good TV watching.
I know exactly what you mean... When are cell phone makers going to get it. All I want is a 52" Plasma Screen HDTV Dolby 6.1 system built into my phone, and why does no one make a 6MP camera phone with live video conferencing? Why can't I play the latest games on my phone... I'm tired of connect 4, I want to play something with great graphics like Doom 3. I hate getting disturbed while I'm taking pictures, watching tv, playing games, and browsing the internet, so why don't these companies give me the option to turn off incoming calls?
Ok... I think I'm done ranting sarcasticly now.
Isn't there more important things for these phone makers to be worrying about... you know... like security? With all those recent articles about how bluetooth phones just surrender to anyone clever enough to know what bluetooth is, one would think that would be a priority. Maybe they could put their R&D team to work on finding a way to not rape their customers.
out cs+(good?goodcs:badcs)+exclimation;... then you deserve to be shot anyhow. I think it's nice that Java's String class is integrated directly into the language, not the more arcaic char* format.
Use streams the way they were intended to be used. You can equally screw up any language's strings. Just because "a"+"b" works in Java, or any other language, doesn't mean you should do it. If you are using JSP, the correct form is done for you.
It seems to me that you are looking for a Holy Grail String class, which to me, is a very bad idea. Small classes that do only what they have to is a pretty common quality amongst well designed systems. Knowing which class to use and how to use it is very basic knowledge about a language. If you want to complain about Java's syntax, feel free to. I'm all about that. There's a lot of things I would like to go back and change about Java's syntax, I wished it was more like Python, but instead, it was based on C++, because that was what was popular at the time. I also would like to see the GUI handled as an abstract model, like XUL, that could be altered with DOM in realtime, and used message passing for events, thus removing all the whole threading and layout issues that we have now. (If anyone is up for creating the second, I'm willing to dedicate some time to it.)
My theory is that people complain about how the Strings in Java aren't "intuitive" because they are too lazy to learn the language, and they can't very well say "Java has too rich of a class library". It's very unlike C/C++ in that it actually comes with all the functions you usually have to have libraries for. Java's 16M JRE probably comes with more functionality than your 200M/usr/lib.
If you're just doing the stuff typically done with PHP, you aren't ever going to need more than 64M. The problem comes in when you are like me, with Gigabytes of data in tables, and there is no way of setting up any key on a table that can help, you can at least keep around common information in memory. Or if you are generating charts/graphics on the fly, you'll probably want to keep those around too. If all you are doing is querying a DB and returning HTML, you are never going to need more than the 64M that you'll get. In fact, you should be fine in probably 8-16 depending on how large your query results are and if you are running any kind of persistance layer other than JDBC. For the same features, Java isn't going to consume much more memory than PHP. You may want to check out something like Jetty. The advantages you get are complete user/process isolation (IE security and stability). That's going to cost you in memory, because you need several copies of libraries and VMs open. That's why people don't bill you on PHP memory usage, because it's not possible to isolate your runtime without you running apache yourself. You go run your local copy of Apache and PHP to isolate yourself from other users, then come back to complain on a level playing field.
Eclipse will run just fine on 32M, with all the completion loaded on any pretty much any sized project. Eclipse seems to have memory management built in. When I run out of memory, it tries to unload editor pages and perspectives that aren't being actively used. You can run ANT externally if you think there is a memory leak, but I've had Eclipse open for weeks on the default setting. Several builds, about 50+ edited files, CVS sync every few hours, and debugging. WebSphere Studio is pretty bad because it runs WebSphere right in the same VM, and that eats up the memory fast.
I have VS.Net installed, and it's definately slow on my computer in comparison with Eclipse. Eclipse has a little longer start-up time, but after it's loaded, I can create projects, compile, test, etc. very snappy. Eclipse indexes every single file you have, and parses them in real time. It compiles on save. VS.Net requires you to actually build the "solution" every time, and it still doesn't feel as quick doing general editing.
By default, the last time I checked, all Java applications are restricted to a 64M heap. All the java objects in Eclipse fit into 64M. Anything more than that is probably going to be JIT compiled code and the VM.
And you just tell me what kind of graphical development environment works better in 256M of ram. X+Gnome+Daemons+kernel eat up most of my memory. I've done tests limiting Eclipse's memory with -Xmx. You can usually get it to run in 5M. AIM uses more memory than that, and Eclipse is an IDE. Set up the VM properly. JNLP/WebStart has tags for this. Most of the VM gets put in swap after JIT, which leaves pretty much only the heap and code to consume memory.
If you're restricted to 64M, your hosting solution is obviously for trivial web applications. RAM is cheaper than your paycheck, unless you live in a 3rd world country. Where I work, we have a pretty trivial web application, and I throw about 2Gig of RAM at it because I want to keep as much data in memory as possible for response times.
If you want to go back to "char*", no one is stopping you. "char string[]=new char[80];" works just fine. Then you can convert to a String, put it in a StringBuffer, or use low-level array copying (array copy functions in System).
I think the other classes cover all the common cases though. Don't build everything in Strings when you are getting ready to put it on the network! Use a BufferedOutputStream and let Java handle it, and dont do stuff like:
out.writeln("Cheese is "+ (good?"good":"bad")+"!");
Doesn't it just make more sense to:
out.write("Cheese is "); out.write((good?"good":"bad"); out.write("!\ n");
My point being that concatonating strings with + forces the creation of a StringBuffer, which is useless considering that the output stream is buffered.
That's just my pet peeve on poor String usage in Java. There are easily 20 silly things that the average programmer will do when not thinking. The String API isn't too shabby. It's much better than being forced into writting your own routines, or having to include 3rd party libraries to achieve the desired effect, which is the case with most compiled languages.
A possible motivation would be more advertising. They could append a text add to the bottom of incoming messaged. Also, that would give them one more playing field to compete with Yahoo on. It's an application that they can have on every client's computer to get information to them... They may put RSS feed notification in it just so they can get you to click a link and see another ad. There's a lot of nifty things they could do with XMPP, but who knows if they'll venture into it.
That said, I really wished it would help, but to most people, it would just be another messenger that isn't compatible with their's. I plan on fighting this IM thing as much as I can too. I plan on branding an XMPP client and running a server for the place where I work for getting info out to their clients. The business is such that they advise people on Stock/Option trades, so speedy delivery may give them an advantage over just E-Mail. Right now, they use Yahoo for a lot of stuff, and for no good reason. Since our clients need to run applications on their computers to get at other services, I'm going to roll them in there together.
The best thing that could happen is a better XMPP server. Have you ever tried to run a XMPP server and keep all the gateways up. There is no real seperation, even when you have different processes. Back when I was running one, the Y! gateway would find a way to take the whole thing down, and I was the kind of guy that had XFree86 4.0 straight off the CVS running just fine. I think it should be so easy to install and extend that there is no excuse to not run it as your company-wide messenger, and you should be ostracized from/. and SF.net for not being reachable via XMPP. Slashdot should notify my of any replies to this message via XMPP!
Maybe we should start with/. Why not give away a @slashdot.org JID with a subscription... I might actually buy one then. Strike a blow for open standards!
I've been working on a stock/option database for the past 6+ months. I have a good idea where the increase has come from. When they moved from one server to another, it probably did the equivalent of clustering on a key. Just so you can see how big of a difference this can make...
A single point of information contains date, symbol(probably and id), open, high, low, close, volume, and sometimes open interest, bid, and ask. All those fields combined are probably going to run you about 40 bytes. There are about 100,000 options and 20,000 stocks traded on any given day in the US. If you store only daily information, you are looking at about 12G of data over 7 years. A key is pretty much useless because of the seek times of finding 40byte peices over 12G because of seek times, unless the data table is ordered by the key. Simply clustering the table, or in this case, exporting and reimporting the data, will make a very significant difference.
You don't know how many times I've been tempted to just use the filesystem. Filesystems are good at keeping files from fragmentation, and they also usually pre-allocate a certain amount of data (a whole block). I wished PostgreSQL supported some kind of preemptive clustering, then the world would be a much better place for us dealing with ridiculous number of rows in a table.
Slashdot Mirror
I like your last paragraph. That's very accurate with what I would call the real world of Admin. If you are spending a significant amount of your time worrying about who to blame when it goes wrong, then you sure aren't doing much work yourself. Accountability is BS, when it's not working, the Admin is always held accountable, because that's what they are paid to do. If you can't install/configure the software running on your servers, then you aren't qualified for your job. I'm paid to make things work, not to point fingers at other people when it doesn't. I run Debian because in the many years that I have, it has never let me down. The only downtime I've had was from a kernel compile issue, and that was my fault. Well... there has been other downtimes, but they've been from third parties installing firewalls without allowing my machines through, which were quick enough to fix, but I was the one that everyone looked to for the solution, not the support of some third party that are taking support fees.
I have to comment on this...
:)
There are plenty of good business reasons to want to use Debian... the very same reasons you or I use it.
1) Security updates are done quicker than recompiling/manually installing (The competition is catching up).
2) Software installation to a new machine will take less time on a Debian system because it will update to the latest versions automatically instead of applying patches over the original install (competition is catching up).
3) More software packages prepackaged means that there are fewer custom compilations/installs, which means installing/upgrading client machines will take less time.
4) Setting up your own APT server means you can distribute your own upgrades internally, and even package non-standard software yourself. This means you can write one install/setup/upgrade script for oracle, and have it automatically propogate through the network instead of installing it on a per machine basis.
Every one of these points saves time. If a company is under pressure right now to save money, applying some of that presure on IBM might be a good way to get the ball rolling toward getting support for Debian. IBM only supports SuSE and RedHat because that's what everyone else uses. There is enough room in the market for another supported distro, especially one as easy to support as Debian.
I wouldn't sacrifice support, because that would put your job on the line, but I would lobby them to ask IBM to support Debian. If enough people in your position do, they'll add it to the supported list. You might want to have them run a test on the next server upgrade/install by installing Debian on it. If that means that IBM doesn't get service fees for that server, and you tell them so, then they'll start paying attention. You're company can always switch a single, not-so-critical system to a supported platform at any time without a significant loss. You just have to convince them that the potential economical gains are significant enough. If that server sits in the corner doing it's job without anyone touching, they'll start to see the wisdom. If you suggest something like a single server as a test bed, they'll see it as more of an experiment to try to save money, and if it fails, it probably won't be your job, but if it succeeds, and you implement it company wide and save a lot of money, then you will probably have eliminated a need for your job, and your boss will get a raise from the portion of your no longer needed salary.
Good, good... I like your logic. What you're trying to say is that even though company X offers what the people want for about the same prices, people will stick with Verizon who tells customers what they want. Last time I checked, consumers drove the market, not the other way around. All the other reasons you mention are fine if no one else is offering the service that the customer wants, but that clearly isn't the case, now is it?
Most of the power used by LCD is still going to be the backlight. The LCD itself doesn't even get warm itself. You may loose a few few minutes of battery life, who knows.
I like to use the time tested Hole(TM) technology of keeping things safe. The oldest data in existance is a well preserved beastiality pornography collection stored on the wall of a cave.
The government has been using it for years to store information for both security and safety reasons. In fact, I bet your dog uses the very same technology for storing his snacks.
Also see the "Don't put all your eggs in one basket" technology.
Anyone read any news lately?
I was about to say that if they started using Antimony in their solder, they probably have bigger problems than the Lead. :)
It's already been mathematically proven that capitalism is not the most effecient economy. The extent of government's involvement should be limited to keeping the playing field level and trying to ensure the public's interests as a whole (where capitalism breaks down... AKA the free-loader problem).
You actually imply that capitalism isn't a part of government.
Capitalism is a form of economy where anything goes (economically). This is bad because when "anything goes"/"lassez faire" economic principals are applied, it means that any given company will do anything within law to destroy competition. The reason why capitalism works at all is that competition exists. If you were forced to buy your food from only one company, then you would really be screwed, because they could charge anything they wanted. If you draw the supply and demand curves, you would see that they optimize in a position where some people will die. It is possible for capitalism to reach such a place in "lassez faire" (some people call this "pure") capitalism. This is basically what Microsoft has on the small businesses of the world, and no doubt, some of them have gone under due to expenses of overly priced software. This is bad for the market as a whole.
So, my point is that capitalism as a whole is so bad that it requires government involvement, but because we are capitalistic, the government can be bought easier than the competition. You're not going to find people getting elected if they don't support enough big-money special-interest agendas in order to get funded.
Corperations, as we know them today, were tacked onto capitalism. There's just too many rights for a company. Lobeying is nothing more than buying votes. If employees could afford to do so, they could afford lower wages. Because of the falure of corperations to work properly, we had unions crop up to be the other great evil. So because of lobeying and stupid special interests, we now have a special interest government where the government represents a million special interest groups instead of the population as a whole.
Capitalism and polotics got too mixed up.
I know that every fax machine is compatible with every other one for a reason, because the spec is good enough. It's just data over a 9600 or 19200 baud stream that's been converted in the standard way to an audible sound. There are data and fax tones, and it's not unreasonable to require them in order for your fax machine to work properly.
You would think for compatibility sake the telcos would have devices to detect digital and just use modems (in the real definition, not the device) to forward the digital signals through, or even better, someone create Fax over IP.
The price of a telephone and internet connection is about as much as my SprintPCS, but I get free long distance, all calls after 7 or on the weekend, and unlimited internet at rates at least a little better than a 56K modem. Oh yeah, and I could hook it up to a laptop just about anywhere in town (and along every interstate) and post to slashdot. :) /. responsibly... don't /. and drive.
Well, under Windows and Mac OS X, you don't need scripts. Under Linux you need them for Executable Jar format because in order to make linux run an executable jar, there are about 8 pages of instructions to do on every machine to make it work. It's not a failing with Java, but a snobbish attitude of distros, which hopefully with Kaffe, etc. that attitude will change. You can just double click jar files on every other platform. Linux's idea of a launcher forces you to use a shell script, even for perl and python, and it forces you to modify your file to support Linux instead of the more proper way of the OS supporting the program. Don't ever write a scripting language where # isn't a comment, else you'll be just as screwed.
If it were done right, all files would have a mime type attribute, and user specific table would specify how to run a file with that mime type.
There is a Java WebStart implementation for Linux that works great.
If you want to refer to a directory of jars, you need to use the boot class path parameter to the VM.
Most people, however, will either use a manifest file:
manifest.mf:
Class-Path: main.jar lib/library.jar lib/otherlib.jar
Main-Class: org.slashdot.example.MainClass
(Don't for get the blank line at the end).
And/Or they will use WebStart, where you declare what you need in XML, and it can be launched and is automatically updated through the internet when available.
All this is free of course, and so is Ant, which you can use to automatically compile and build your directory structure, including your executable jar file and any libraries you need.
If you have a hard time running a Java application, it's the developers fault. There are PLENTY of ways to make it easy... easier than installing software on any other system.
It's just for the GUI :)
.Net app.
:)
Don't you have a shiney new GMail account and use GTray already? GTray is a
Maybe it works with Mono, but I doubt it because I think it uses windows forms, and we all know that Mono doesn't really support that so well yet.
I don't hold it against them because there really is no point in running a ReiserFS browser on more than one platform.
YAReg
http://yareg.akucom.de/index.html
works for me now.... I have to say I would much prefer a real driver, but beggers can't be choosers.
I use Jabber for Yahoo, MSN, and AIM.
:)
I know a lot of people run Trillian, GAIM, etc. as well.
My only point is to say that it's not either/or. If google pushes underpants, I would try them. If enough people give it a try, and they have enough cool features like GMail, they will stay. Searching your old IM's is a nice way to start.
So... I think there's always room for one more IM protocol. The only reason AIM is big is because Grandma uses AOL, and thinks that AIM is IM. I think grandma knows how to google too.
I'm much too lazy to go look up the specs and calculate everything out, but I'll sure Google for it :)
1 _T HR.htm
:)
_ a_display_device/)
http://www.benchtest.com/gp_Temp4.html
is a guy doing just this.
You need to know how to do your resistor calculations from basic electronics/physics. Thermistors have a temperature range and a corresponding resistance range. You have to calibrate it yourself and you'll probably have to put in something to help with the logarythmic nature of the themistor.
http://www.eidusa.com/Electronics_Kits_EUSB_To_
has some information and formulas for calibration.
Want to control external devices from your computer?
I suggest getting a serial servo controller because they are fun. If you want to just turn something on and off, it's a bit overkill to put a servo to actually flip a switch, but it's still really fun.
If you really want to do it the right way:
Get X10 if you use a space heater/wall AC... you may have to still use a really big relay to handle the draw. Don't forget to check the maximum capacity of your electronics.
Use the parallel port to trigger a relay and run the connection wires to the mercury switches in your normal thermometer.
Also, you can put in photo-resistor/transistors to measure light level, and use X10 to control your lighting level of a room. You could get a motion detector and hook it up to your joystick port's buttons, but you'll have to disect the motion sensor.
You can set up trip alarms pretty easy with infrared emitters and detectors.
Video for Linux is cool enough that you can get a cheap X10 Cam and write simple algorithms to do neat stuff.
I've actually helped build a system that used an FM reciever piped to voice recoginition software that the guy could turn his lights on from outside just by saying the right word. We also set up a servo controlled robotic arm with a laser pointer and a web-cam. The site let you click on the picture and it would point the laser at that point.
I'm really not impressed with web-enabled appliances. It would be much more useful if the appliances were more aware of what was going on. One of the coolest, useful wacky ideas that I've seen is the Java toaster that burned the forcast into toast. (http://www.theregister.co.uk/2001/06/04/bread_as
There was talk of making a device for market that let people advertise on toast, IIRC.
Finally... another neat way to make your computer do cool stuff is to get a cheap atmel chip, hook it up to your serial port, and program it to do whatever you want. You can hook up better I2C sensors pretty easily then too. Some of those have exact ranges precalibrated and they are accurate to 10bit.
Well... I've run out of cool ideas for you to play with... just search on google and you'll find a ton of hobbiest out there ready to share all the information you need to hook anything you want up to your computer.
For 25 cents, you could buy a themal resistor from Radio Shack and just push it into your joystick port.
>> The screens are too small for good TV watching.
I know exactly what you mean... When are cell phone makers going to get it. All I want is a 52" Plasma Screen HDTV Dolby 6.1 system built into my phone, and why does no one make a 6MP camera phone with live video conferencing? Why can't I play the latest games on my phone... I'm tired of connect 4, I want to play something with great graphics like Doom 3. I hate getting disturbed while I'm taking pictures, watching tv, playing games, and browsing the internet, so why don't these companies give me the option to turn off incoming calls?
Ok... I think I'm done ranting sarcasticly now.
Isn't there more important things for these phone makers to be worrying about... you know... like security? With all those recent articles about how bluetooth phones just surrender to anyone clever enough to know what bluetooth is, one would think that would be a priority. Maybe they could put their R&D team to work on finding a way to not rape their customers.
Well... the C++ way to have done it would have been:
... then you deserve to be shot anyhow. I think it's nice that Java's String class is integrated directly into the language, not the more arcaic char* format.
/usr/lib.
out "Cheese is "(good?"good":"bad")"!"endl;
Which would be like the second. If you are doing:
CString cs=new CString("Cheese is ");
CString goodcs=new CString("good");
CString badcs=new CString("bad");
CString exclimation=new CString("!\n");
out cs+(good?goodcs:badcs)+exclimation;
Use streams the way they were intended to be used. You can equally screw up any language's strings. Just because "a"+"b" works in Java, or any other language, doesn't mean you should do it. If you are using JSP, the correct form is done for you.
It seems to me that you are looking for a Holy Grail String class, which to me, is a very bad idea. Small classes that do only what they have to is a pretty common quality amongst well designed systems. Knowing which class to use and how to use it is very basic knowledge about a language. If you want to complain about Java's syntax, feel free to. I'm all about that. There's a lot of things I would like to go back and change about Java's syntax, I wished it was more like Python, but instead, it was based on C++, because that was what was popular at the time. I also would like to see the GUI handled as an abstract model, like XUL, that could be altered with DOM in realtime, and used message passing for events, thus removing all the whole threading and layout issues that we have now. (If anyone is up for creating the second, I'm willing to dedicate some time to it.)
My theory is that people complain about how the Strings in Java aren't "intuitive" because they are too lazy to learn the language, and they can't very well say "Java has too rich of a class library". It's very unlike C/C++ in that it actually comes with all the functions you usually have to have libraries for. Java's 16M JRE probably comes with more functionality than your 200M
If you're just doing the stuff typically done with PHP, you aren't ever going to need more than 64M. The problem comes in when you are like me, with Gigabytes of data in tables, and there is no way of setting up any key on a table that can help, you can at least keep around common information in memory. Or if you are generating charts/graphics on the fly, you'll probably want to keep those around too. If all you are doing is querying a DB and returning HTML, you are never going to need more than the 64M that you'll get. In fact, you should be fine in probably 8-16 depending on how large your query results are and if you are running any kind of persistance layer other than JDBC. For the same features, Java isn't going to consume much more memory than PHP. You may want to check out something like Jetty. The advantages you get are complete user/process isolation (IE security and stability). That's going to cost you in memory, because you need several copies of libraries and VMs open. That's why people don't bill you on PHP memory usage, because it's not possible to isolate your runtime without you running apache yourself. You go run your local copy of Apache and PHP to isolate yourself from other users, then come back to complain on a level playing field.
Eclipse will run just fine on 32M, with all the completion loaded on any pretty much any sized project. Eclipse seems to have memory management built in. When I run out of memory, it tries to unload editor pages and perspectives that aren't being actively used. You can run ANT externally if you think there is a memory leak, but I've had Eclipse open for weeks on the default setting. Several builds, about 50+ edited files, CVS sync every few hours, and debugging. WebSphere Studio is pretty bad because it runs WebSphere right in the same VM, and that eats up the memory fast.
I have VS.Net installed, and it's definately slow on my computer in comparison with Eclipse. Eclipse has a little longer start-up time, but after it's loaded, I can create projects, compile, test, etc. very snappy. Eclipse indexes every single file you have, and parses them in real time. It compiles on save. VS.Net requires you to actually build the "solution" every time, and it still doesn't feel as quick doing general editing.
By default, the last time I checked, all Java applications are restricted to a 64M heap. All the java objects in Eclipse fit into 64M. Anything more than that is probably going to be JIT compiled code and the VM.
And you just tell me what kind of graphical development environment works better in 256M of ram. X+Gnome+Daemons+kernel eat up most of my memory. I've done tests limiting Eclipse's memory with -Xmx. You can usually get it to run in 5M. AIM uses more memory than that, and Eclipse is an IDE. Set up the VM properly. JNLP/WebStart has tags for this. Most of the VM gets put in swap after JIT, which leaves pretty much only the heap and code to consume memory.
If you're restricted to 64M, your hosting solution is obviously for trivial web applications. RAM is cheaper than your paycheck, unless you live in a 3rd world country. Where I work, we have a pretty trivial web application, and I throw about 2Gig of RAM at it because I want to keep as much data in memory as possible for response times.
I think the other classes cover all the common cases though. Don't build everything in Strings when you are getting ready to put it on the network! Use a BufferedOutputStream and let Java handle it, and dont do stuff like:Doesn't it just make more sense to:
My point being that concatonating strings with + forces the creation of a StringBuffer, which is useless considering that the output stream is buffered.
That's just my pet peeve on poor String usage in Java. There are easily 20 silly things that the average programmer will do when not thinking. The String API isn't too shabby. It's much better than being forced into writting your own routines, or having to include 3rd party libraries to achieve the desired effect, which is the case with most compiled languages.
I hope so.
/. and SF.net for not being reachable via XMPP. Slashdot should notify my of any replies to this message via XMPP!
/. Why not give away a @slashdot.org JID with a subscription... I might actually buy one then. Strike a blow for open standards!
A possible motivation would be more advertising. They could append a text add to the bottom of incoming messaged. Also, that would give them one more playing field to compete with Yahoo on. It's an application that they can have on every client's computer to get information to them... They may put RSS feed notification in it just so they can get you to click a link and see another ad. There's a lot of nifty things they could do with XMPP, but who knows if they'll venture into it.
That said, I really wished it would help, but to most people, it would just be another messenger that isn't compatible with their's. I plan on fighting this IM thing as much as I can too. I plan on branding an XMPP client and running a server for the place where I work for getting info out to their clients. The business is such that they advise people on Stock/Option trades, so speedy delivery may give them an advantage over just E-Mail. Right now, they use Yahoo for a lot of stuff, and for no good reason. Since our clients need to run applications on their computers to get at other services, I'm going to roll them in there together.
The best thing that could happen is a better XMPP server. Have you ever tried to run a XMPP server and keep all the gateways up. There is no real seperation, even when you have different processes. Back when I was running one, the Y! gateway would find a way to take the whole thing down, and I was the kind of guy that had XFree86 4.0 straight off the CVS running just fine. I think it should be so easy to install and extend that there is no excuse to not run it as your company-wide messenger, and you should be ostracized from
Maybe we should start with
I've been working on a stock/option database for the past 6+ months. I have a good idea where the increase has come from. When they moved from one server to another, it probably did the equivalent of clustering on a key. Just so you can see how big of a difference this can make...
A single point of information contains date, symbol(probably and id), open, high, low, close, volume, and sometimes open interest, bid, and ask. All those fields combined are probably going to run you about 40 bytes. There are about 100,000 options and 20,000 stocks traded on any given day in the US. If you store only daily information, you are looking at about 12G of data over 7 years. A key is pretty much useless because of the seek times of finding 40byte peices over 12G because of seek times, unless the data table is ordered by the key. Simply clustering the table, or in this case, exporting and reimporting the data, will make a very significant difference.
You don't know how many times I've been tempted to just use the filesystem. Filesystems are good at keeping files from fragmentation, and they also usually pre-allocate a certain amount of data (a whole block). I wished PostgreSQL supported some kind of preemptive clustering, then the world would be a much better place for us dealing with ridiculous number of rows in a table.