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Ljava.lang.String; Error

This is a simple one. You're asking java to return an Array as a string.

Solution: Put Arrays.toString( ) around your Array.

Jquery Slideup Jerking Effect In IE9

This website has code to help get rid of the jerking effect on Jquery SlideUp in IE9: https://siderite.dev/blog/jquery-slideup-flickers-in-internet.html

You just add this code after you include your Jquery library:

(function(){
// Define overriding method.
jQuery.fx.prototype.hide = function(){

// Remember where we started, so that we can go back to it later
this.options.orig[this.prop] = jQuery.style( this.elem, this.prop );
this.options.hide = true;

// Begin the animation
this.custom(this.cur(), 1);
}
})();

Raspberry Pi - No Ethernet Caused By Charger

I was using the following charger, but I couldn't get my Raspberry Pi to connect over Ethernet (ethernet lights showed no link): http://www.amazon.com/gp/product/B0038HYPZS

The charger was definitely the problem. I swapped it with a Motorola OEM charger and the Ethernet started working again. I did some quick googling, and haven't seen many reports of this issue yet. I have the Model B, Rev 2.0 board with 512MB RAM.

LDAP_ADD PHP - Object Class Violation

If you are trying to use php's ldap_add to add an user and are getting an object class violation, try to copy all the fields of a working user exactly. Most likely you are missing some of the required fields of the objectclass you are trying to add.

Reading RFID With Raspberry Pi (or any linux device) + Reader

I'm using the following Parallax USB RFID reader: http://www.parallax.com/Portals/0/Downloads/docs/prod/audiovis/28140-28340-RFIDreader-v2.2.pdf

First you will need to ensure you have PySerial installed by trying to "import PySerial" while running Python's IDLE. If you receive an error:
    Install PySerial:
      1. Install python's setuptools: apt-get install python-setuptools
      2. Install PySerial: pip install pyserial

    Once you have PySerial installed, open IDLE again and use the following code to see output from the reader:

    #! /usr/bin/python
    import serial
    import time
    ser = serial.Serial('/dev/ttyUSB0', 2400, timeout=1) # replace '/dev/ttyUSB0' with your port
    while True:
    response = ser.read(12)
    if response <> "":
    print "raw: " + str(response)
    print "hex: " + str(response[-8:])
    print "dec: " + str(int(response[-8:], 16))
    time.sleep(1)
    ser.close()
    view raw rfid.py hosted with ❤ by GitHub

    Why didn't ser.read(12) return the same unique identifier as what is written on the fob?:
    • If the key on the card says 30788590 and the reader returns 3501D5CBEE. The "1D5CBEE" part is the card number. Try going from the card number in DEC to HEX it in the windows calculator while it's in scientific mode if you don't believe me.

    "margin-left: auto;" and "margin-right: auto;" Not Working In IE8

    To get something centered within a div in IE8, it requires doing something unusual. I wasn't able to get the "display: block;" trick working. But this worked:

    #super-wrap { position: absolute; width: 100%; text-align: center; } 
    #page-wrap { position: relative; width: 970px; margin: auto auto;  }

    I had to do this to get the InfoGrid (http://css-tricks.com/examples/InfoGrid/) to center in IE8. The div with the ID of #page-wrap already exists, but the super-wrap div needs to be created outside of the page-wrap div.