IllegalBlockSize Exception
Getting javax.crypto.IllegalBlockSizeException: Input length must be multiple of 16 when decrypting with padded cipher?
AC: Why differentiate between Ground and Neutral? Current flows through a conductor connecting points at different potentials.  Leaving aside multi-phase details, common/conventional AC systems use a 3-wire setup:   Wire-1: a line/live/hot/phase wire presenting a point that oscillates between 2 potentials. Wire-2: a neutral wire presenting a point of unknown/unspecified and varying potential, that nevertheless presents some fixed/specified potential difference to Wire-1 at least some of the time. Wire-3: a ground/earth wire presenting a point at 0V potential difference to its immediate physical surroundings.   Wire-1 and Wire-2, in addition to some device that is to be powered, are used to construct a closed electrical circuit. Wire-3, leaving aside EMI/shielding concerns, is used to ensure that current will flow through it, rather than the device's user, if there ever occur any faults and the device's user comes in contact with Wire-1 or Wire-2.  Additionally to this however, Wire-2 and Wire-3 are at some point connected. This is done to ensure that Wire-2's potential remains close to that of Wire-3 .. which seems to be important for some reason.  Now the part I don't understand is why there needs to be a distinction between Wire-2 and Wire-3 at the power socket, if there is none a few meters further down the line.  I have tried to look this up, but all answers I could find so far seem incomplete. The answers depend on how the question is phrased:   If the question is phrased as "Why do we need Wire-3 in addition to Wire-2" the answer is because "Wire-2 may be at a substantial potential difference to its surroundings/user and thus endanger him/her if he/she ever comes in contact with it or Wire-1". If the question is phrased as "Why do we need Wire-2 in addition to Wire-3" the answer is because "Wire-2 is needed to form a closed electrical circuit" or phrased somewhat differently "Wire-2 is needed to create a potential difference to Wire-1 and thus for current to flow" .. with the argument further being that when taking practical considerations into account Wire-3 can't provide a reliable/stable potential difference to Wire-1 like Wire-2 can.   This doesn't really answer why there's a need to differentiate between Wire-2/Wire-3 though, considering how    Wire-3 remains Wire-3 and maintains 0V potential difference to its surroundings/user, regardless of whatever else happens around it .. since that is what it's supposed to do, or phrased differently, since that is the reason for Wire-3 being useful in the first place .. right?   and   Wire-2 is connected to Wire-3   What am I missing here?    Why is it safe to touch Wire-3 but not Wire-2, or why can Wire-3 provide a level of protection that Wire-2 can't?  Why differentiate between Wire-2 and Wire-3 at the power socket but then connect them further down the line? Flattening a shallow list in Python Simplify the expression $\binom{n}{0}+\binom{n+1}{1}+\binom{n+2}{2}+\cdots +\binom{n+k}{k}$ I have two tensors that i must calculate double dot product. matrix A is rank 2  and matrix B is rank 4. I want to multiply them with Matlab and I know in Matlab it becomes: A : B = trace (A*B) but it has one error and it says: Inner matrix dimensions must agree So how can I solve this problem? anybody help me? Thanks Single word describing a person new in something What is a word for someone who is totally new in something or participates in something for the first time? Replace Tag of and xml file after pattern matching using shell I have an input xml file like below INPUT FILE &lt;ReconSummary&gt; &lt;entryName&gt;Total Deep&lt;/entryName&gt; &lt;Code&gt;777&lt;/Code&gt; &lt;License&gt;L&lt;/License&gt; &lt;Tran&gt;H20&lt;/Tran&gt; &lt;job&gt;1234&lt;/job&gt; &lt;/ReconSummary&gt;   &lt;ReconSummary&gt; &lt;entryName&gt;Total Saurav&lt;/entryName&gt; &lt;Code&gt;666&lt;/Code&gt; &lt;License&gt;L&lt;/License&gt; &lt;Tran&gt;H20&lt;/Tran&gt; &lt;job&gt;1234&lt;/job&gt; &lt;/ReconSummary&gt;   &lt;ReconSummary&gt; &lt;entryName&gt;Total Ankur&lt;/entryName&gt; &lt;Code&gt;555&lt;/Code&gt; &lt;License&gt;L&lt;/License&gt; &lt;Tran&gt;H20&lt;/Tran&gt; &lt;job&gt;1234&lt;/job&gt; &lt;/ReconSummary&gt;  I want to comment the tag if i find the pattern &quot;Total Deep&quot; so that the output file looks like below OUTPUT &lt;!--&lt;ReconSummary&gt; &lt;entryName&gt;Total Deep&lt;/entryName&gt; &lt;Code&gt;777&lt;/Code&gt; &lt;License&gt;L&lt;/License&gt; &lt;Tran&gt;H20&lt;/Tran&gt; &lt;job&gt;1234&lt;/job&gt; &lt;/ReconSummary&gt;--&gt;   &lt;ReconSummary&gt; &lt;entryName&gt;Total Saurav&lt;/entryName&gt; &lt;Code&gt;666&lt;/Code&gt; &lt;License&gt;L&lt;/License&gt; &lt;Tran&gt;H20&lt;/Tran&gt; &lt;job&gt;1234&lt;/job&gt; &lt;/ReconSummary&gt;   &lt;ReconSummary&gt; &lt;entryName&gt;Total Ankur&lt;/entryName&gt; &lt;Code&gt;555&lt;/Code&gt; &lt;License&gt;L&lt;/License&gt; &lt;Tran&gt;H20&lt;/Tran&gt; &lt;job&gt;1234&lt;/job&gt; &lt;/ReconSummary&gt;  Since i am new to shell scripting, can anyone help me out as to how i can apply this with the help of shell scripting? Is "chutzpah" used by non-Jewish English speakers? I am currently undergoing a full Apostol Calculus I reading, and with few chapters left I've began planning what other books to read. I was thinking about finishing both Apostol Calculus l and ll, and then read Apostol mathematical analysis. I'm not pretty sure whether these are the best books or if they will provide me with a strong math basis. I've already taken calculus i, ii, iii and linear algebra. The reason I've chosen Aapostol volume 1 and 2 is that I've heard they cover almost all the topics I've seen and will see in the next semester/s. I would appreciate if somebody could give me some advice about this. I really like to have a book that really gives me hard and challenging problems. I don't know whether to read Spivak Calculus book or not. I am looking for a quick way to sleep without closing the lid, or using the mouse.  If it matters, I have Lion version OS and a MacBook Air. Determining bare earth DEM from unclassified LAS file? I have data in LAS format with RGB values created from aerial photogrammetry using a UAV. I am  trying to find a solution to extract the bare earth DEM from the point cloud.   I have tried SAGA, Fusion, MCC-LIDAR, but it is seems they need the LAS file to be already classified (which it naturally isn't). Can anyone point me in the right direction with a brief explanation of the process?   Generally, I would need to process about 100 mill points at a time (can tile them if needed). Evaluation of ratio of two binomial expression How to delete files from a folder using a list of file names in windows? i have a folder with 2K+ files in it, i need to delete around 200, i have a txt file with all the file names i need removed ordered in a list, how do i remove the specific files from the folder using the list? (OS is windows 7) Is there a systematic way to obtain all conserved quantities of a system? I'd like to know whether, given a system, there's a way to obtain all the conserved quantities. For instance if the system consists of electric and magnetic fields, the fields must satisfy Maxwell's equations. These equations are invariant under many transformations (Lorentz transformation, rotations, spatial and temporal translations, etc. By the way is there a way, maybe from group theory, to find all the possible transformations that leaves the equation(s) invariant?) which imply as many conserved quantities thanks to Noether's theorem. In wikipedia I can see an equation that seems to give all the conserved quantities () but it involves the Lagrangian and I'm not sure whether the formula is valid for all systems whose Lagrangian is possible to obtain. How to keep leading zeros in PHP integer Should edits with only minor code improvements be accepted. As an example, I'm reviewing an edit that changes all double quotes to single quotes and renames a variable in some javascript. With the exception of the variable rename (which is not entirely necessary), the edit is frivolous. Should I accept on the merits of a debatable variable name change? After upgrading my laptop from karmic to lucid, my fat32 partition won't mount automatically. I get the message:  The disk drive for /osshare is not ready yet or not present Continue to wait; or Press S to skip mounting or M for manual recovery   Funny thing is, if I skip, then /osshare/ is mounted once I log in.   I've a similar setup on my desktop, and it works fine. Fstab on desktop:  UUID=4663-6853  /osshare        vfat    utf8,umask=007,gid=46 0       1   /etc/fstab on laptop:  UUID=1234-5678 /osshare vfat utf8,auto,rw,user 0 0 , Laser Interferometer Gravitational-Wave Observatory, is a large-scale physics experiment aiming to directly detect gravitational waves. The device measures the phase shift laser beams.  If I understand this well, the measurement assumes that a suitable gravitational wave reduces and prolongs one of the tubes and the extension will take effect in the phase-shifting laser beams.  But I think if there's a gravitational wave that passes through it, it will affect everything, even the laser beam. This means that when the wave lengthens or shortens the tube, it also lengthens or shortens the wavelength of the laser beam.  In my opinion, therefore, this device does not work. Or am I wrong? If you view the Earth from far enough away can you observe its past? Shell Script for logging into a ssh server I tried writing a shell script which can do automatic login into a ssh server using password which is mentioned in the script. I have written the following code:  set timeout 30 /usr/bin/ssh -p 8484 root@172.31.72.103 expect  {    "root@172.31.72.103's password"     {       send "password\r"     } }   This code is not running properly, still it is asking for the password. Can somebody please help me in solving this When a word ends in 's' or 'x', do you add 's or just an '? 1) Alex's house      2) Alex' house     When the noun ends with the letter 's' or 'x', do I need to put 's' after an apostrophe or not?  I remember I read some rules related to this in my school grammar book, but now I've forgotten it.