Why StringBuffer is thread safe and why StringBuilder is not. Why the StringBuffer is working best in multi-threading and StringBuilder is in single-threading.   I saw there are methods which are common for both StringBuilder and StringBuffer, then why they are varied in their functions.
What is the main difference between StringBuffer and StringBuilder? Is there any performance issues when deciding on any one of these?
Hypernym for "audiobook", "podcast", "speech", etc.? I am looking for a short and concise term (preferably one word) that can be used as a hypernym for essentially everything that contains (audio) speech (e.g. audiobooks, podcasts, recorded news bulletins, recorded performances of comedians,..).  Does such a term exist? I've thought about 'speech', but that seems to be more adequate for e.g. political speeches, and not so much for audio books and the like. But maybe I'm wrong. How do I close a connection early? Is there a quick way to set an HTML text input (&lt;input type=text /&gt;) to only allow numeric keystrokes (plus '.')? illustrates drag coefficients for several shapes:    It is generally accepted that some variation of the teardrop/airfoil shape has the lowest drag coefficient.  I was wondering what shape has the highest drag coefficient.  The image suggests that it is a flat plate, and that would seem to be an intuitively correct answer, but is that correct?  Is there some other shape (perhaps with a concave front or back relative to motion) that has an even higher drag coefficient? I have recently noticed a huge (>3.5GB) file in the DCIM/.thumbnails folder. I have tried deleting it, but the next time I open the Camera app it rebuilds the file (and locks up the phone, sometimes displaying a "media scanning in progress" message, in the process.)  The total file size of all the (approximately 2,000) photos displayed in the Gallery is around 500MB. There are in addition around 35,000 images in folders which contain .nomedia files to instruct Android to ignore the media therein. The total file size of these is around 1.5GB. The Gallery app is correctly ignoring these images, but I wonder whether the Camera app is misbehaving and actually processing them.  I think this problem has emerged since the ICS upgrade ... either when the phone (Samsung Galaxy Note) was first updated from Gingerbread or at some later date.  Any ideas, please? ref to subsection number only is there a way to reference the subsection part only? Example:  \documentclass{article} \begin{document}  \section{This is my section} For further information see subsection \ref{subsecthree} within this section. \subsection{One} \subsection{Two} \subsection{Three}\label{subsecthree}  \end{document}   Usually gives (without the stars):  1 This is my section For further information see subsection **1.3** within this section.   But I want:  1 This is my section For further information see subsection **3** within this section.   Is that possible?  [Edit] To make it more clear: I am looking for a command that works like \ref, but prints (the arabic number of) the value of the subsection counter at the position of the \label.  ======================= == Solution in LaTeX ==  There is another solution below. This is a different solution I came up with  (I cannot post an answer to my own question, so I put it here):  \documentclass{article}  \newcommand{\labelsubseccounter}[1]{     \renewcommand\thesubsection{\arabic{subsection}}     \addtocounter{subsection}{-1}     \refstepcounter{subsection}     \label{#1}     \renewcommand\thesubsection{\thesection.\arabic{subsection}} }  \begin{document}  \section{This is my section} For further information see subsection \ref{subsecthree} within this section,  which is called \ref{onepointthree}, not \ref{onepointfour}. \subsection{One} \subsection{Two} \subsection{Three}\label{onepointthree}\labelsubseccounter{subsecthree} \subsection{Four}\label{onepointfour}  \end{document}   (I would like to insert the compiled code, but don't know how, sorry) Castellation metal loop connector Joined pipelines Considering a routine such as this one:  alpha() { echo a b c |tr ' ' '\n'; }   which outputs a stream, I would like to take the output stream, transform it, and paste it with the original output stream.  If I take use upcasing as a sample transformation, I can achieve what I want with:  $ mkfifo p1 p2 $ alpha | tee p1 &gt;( tr a-z A-Z &gt; p2) &gt;/dev/null &amp; $ paste p1 p2 a       A b       B c       C   My question is, is there a better way to do this, preferably one not involving named pipes? How to compute $k$'th roots $\!\bmod n$? I have the following equation: $$ n \equiv M^k\mod(b) $$ where n, a, b are integers, and M is unknown. How do I solve this equation to find the M value? Those a and b are public keys of the RSA algorithm and n is the result of encryption. I need to find the encrypted message. How do I enable hardware virtualization technology (VT-x) for use in Virtualbox? I have a doubt. I need help.  Can the basic axioms of equality be presented as "open axioms"?  I) (reflexivity) $\qquad x = x$              II)  (Substitutivity) $\qquad (x = y) \to \big(F (x, x) \to F (x, y)\big)$ states that the relationship between current ( I ) voltage ( V ) and resistance ( R ) is  $$I = \frac{V}{R}$$  However  cause the resistance of a material to go to zero, and as I understand it, as $R \to 0$, $I \to \infty$. Does this present a problem for Ohm's law? How to add a PPA on a server? The server version of Ubuntu does not have the  command. How can I add a  (PPA) to the server without this command? biblatex broken overnight As late as last week my setup for biblatex worked fine. Going back to the same project today not even a minimal file compiles:  \documentclass{article}   \usepackage{biblatex} %\addbibresource{biblatex-examples.bib}   \begin{document}  test%foo\nocite{*}    %\printbibliography  \end{document}   but breaks off with   /usr/local/texlive/2017/texmf-dist/tex/latex/biblatex/biblatex.sty:3776: LaTeX  Error: Missing \begin{document}.  See the LaTeX manual or LaTeX Companion for explanation. Type  H &lt;return&gt;  for immediate help.  ...                                                l.3776   australian,newzealand} ?  /usr/local/texlive/2017/texmf-dist/tex/latex/biblatex/biblatex.sty:3776: Math f ormula deleted: Insufficient symbol fonts. \expandafter -&gt;american|  l.3776   australian,newzealand}   And keeps repeating the last one until    (That makes 100 errors; please try again.)   when I ignore it.  Files without biblatex work as expected.  Using tlmgr to go my two backup versions of biblatex back in time to 1st Jan I still get the same errors.  Could this be another update from the last week or so that causes this?  If I swich back to TL 16 things work as expected. (For my work I need TL 17 because of packages.) YA novel where clumsy boy gains wings I'm trying to remember the name of a novel I read as a pre-teen.  If I recall correctly, it would have come out in the 90s (though it may have been a reprint).  The novel is set in modern times.  I recalled this because I've been reading a lot of urban fantasy lately, and this may be the first 'urban fantasy' book I read - our world, but with a touch of magic.  There's a somewhat clumsy, out of shape teenaged (or almost teenaged) boy who doesn't have a father.  His father had been a stage magician who was constantly frustrated by his son's complete inability to preform stage magic, despite a prediction saying he would have a great or powerful magic.  His father had died before the book started, I don't recall how long before.  The boy does something nice for an old woman (I don't recall what) and she gifts him a magical potion.  A drop of it, rubbed on his shoulder blades, will make him grow wings.  The book follows him for the summer, as he spends his evenings flying.  He makes himself a toga-like shirt out of some old curtains and spends time flying around at night.  I recall one scene where he learns about two children out in the middle of the bay (perhaps the book is set in San Fran?  I don't recall) in a rowboat with one oar.  He saves them (by pulling them back to shore using a rope they had with them) and gets mentioned in the paper as an angel.  At the end of the book, the potion has run out.  There's only a tiny little bit left, and when he rubs it in, it creates only a single feather.  Around that point, the boy realizes that he's no longer getting winded going up several flights of stairs and he's gained a lot of self-confidence.  From what I remember of the copy I read, the cover featured a shirtless boy wearing jeans standing in front of a mirror, looking at the large white feathered wings that had grown from his back. While looking at online code samples, I have sometimes come across an assignment of a String constant to a String object via the use of the new operator.  For example:  String s; ... s = new String("Hello World");   This, of course, compared to  s = "Hello World";   I'm not familiar with this syntax and have no idea what the purpose or effect would be.  Since String constants typically get stored in the constant pool and then in whatever representation the JVM has for dealing with String constants, would anything even be allocated on the heap? We know that any particle moving at speed of light will have infinite mass.  Since even Light has particles. Then what is the size of the Particle? How to imagine this with the mass of light particles. Can I read the hash portion of the URL on my server-side application (PHP, Ruby, Python, etc.)? We know that the needle that is used in a compass is a permanently magnetized ferromagnetic material and commonly steel is used.  If we used an unmagnetized iron needle instead, would it still align with Earth's magnetic field lines? If yes, how? I want to install the latest version of Eclipse but the Ubuntu Software Centre contains an older version.  Is there a PPA or some other way to install latest Eclipse? Please describe the steps for full installation.