design patterns - Multiple instances of Singleton class. Possible? -

-

i found this explanatory link states

ensure class has 1 instance, , provide global point of access it.

i appeared @ interview , surprise asked me too can singleton class have multiples instances, technology being java , objective c. answer question no believe right singleton variable being global shall check if null or not. , null first time.
out of curiosity confirming it. can provide confirmation explanation weather right or wrong.

the word singleton definition(of design patterns) not allows multiple instances, yeah can tweak class create multiple instances won't considered singleton definition


Comments

Post a Comment

Popular posts from this blog

matlab - "Contour not rendered for non-finite ZData" -

-
i'm trying plot frequency characteristic equation using ezplot, matlab gives following warning, "contour not rendered non-finite zdata". have used command plot frequency equations warning , plot display empty , not change axis range well. can please help. appreciated. here's code i'm using. % transfer matrix case-i, thin rotor clear all; clc; ei = 1626; l = 0.15; m = 0.44108; = 2.178*10^-4; i_p = 2.205*10^-5; itr = 0.24; i_pr = 0.479; syms p n; f = [1 l*1i l^2/(2*ei)*1i l^3/(6*ei); 0 1 l/ei -l^2/(2*ei)*1i; 0 0 1 -l*1i; 0 0 0 l]; p = [ 1 0 0 0; 0 1 0 0; 0 -it*p^2+i_p*n*p 1 0; -m*p^2 0 0 1]; p_r = [1 0 0 0; 0 1 0 0; 0 -itr*p^2+i_pr*n*p 1 0; -m*p^2 0 0 1]; = f*p*f*p*f*p*f; b = p_r*f*p*f*p*f; r = a(1,2)/a(1,4); a12_p = 0; a22_p = a(2,2)-r*a(2,4); a32_p = a(3,2)-r*a(3,4); a42_p = a(4,2)-r*a(4,4); ap(2,2) = a22_p; ap(3,2) = a32_p; ap(4,2) = a42_p; ap(4,4) = 1; c = b*ap; m = [c(3,2) c(3,4); c(4,2) c(4,...
Read more

delphi - Indy UDP Read Contents of Adata -

-
i using indy udp server read string of data. however, not know how work adata parameter. can around converting binary using bytetobin function below , convert hex using bintohex1 . feel stupid , works slow. know how can directly results without 2 conversions? thanks!! here codes: procedure tform1.idudpserver1udpread(athread: tidudplistenerthread; const adata: tidbytes; abinding: tidsockethandle); var buf: tidbytes; buffer: string; data_received: string; begin if bytestostring(adata) <> 'hello' begin buffer := hextostring('00'); setlength(buf, length(buffer)); copytidstring(buffer, buf, 0); abinding.sendto(abinding.peerip, abinding.peerport, buf); data_received := bintohex1(bytetobin(adata[1]) + bytetobin(adata[2]) + bytetobin(adata[3]) + bytetobin(adata[4]) + bytetobin(adata[5]) + bytetobin(adata[6]) + bytetobin(adata[7]) + bytetobin(adata[8]) + bytetobin(adata[9]) + bytetobin(adata[10]) + bytetobin(adata[11...
Read more

javascript - Any ideas when Firefox is likely to implement lengthAdjust and textLength? -

-
any ideas when firefox implement lengthadjust andtextlength?..... working svg application. lengthadjust , textlength working fine in chrome not working in fire fox . <svg viewbox = "0 0 500 300" version = "1.1"> <defs> <path id="s3" d="m 10,90 q 100,15 200,70" /> </defs> <g> <text font-size = "20"> <textpath xlink:href="#s3" textlength="205"> short text</textpath> </text> <use xlink:href="#s3" fill="none" stroke="black" stroke-width="1"/> </g> </svg> this implemented in firefox text elements (not textpath or tspan) in case that's ok though can move attribute text element. <svg viewbox = "0 0 500 300" version = "1.1"> <defs> ...
Read more