sorting - Sort the column in a CSV File in Java -

-

i have csv file reads this.

city,job,salary delhi,doctors,500 delhi,lawyers,400 delhi,plumbers,100 london,doctors,800 london,lawyers,700 london,plumbers,300 tokyo,doctors,900 tokyo,lawyers,800 tokyo,plumbers,400 lawyers,doctors,300 lawyers,lawyers,400 lawyers,plumbers,500 hong kong,doctors,1800 hong kong,lawyers,1100 hong kong,plumbers,1000 moscow,doctors,300 moscow,lawyers,200 moscow,plumbers,100 berlin,doctors,800 berlin,plumbers,900 paris,doctors,900 paris,lawyers,800 paris,plumbers,500 paris,dog catchers,400`

now, want sort column of salary , write txt file.

i can access column, not able sort it. new csv reading part of java. can help! how should store each salary value variable.

import java.io.*;  public class main {      public static void main(string args[]) throws filenotfoundexception     {         string csv="c:\\users\\dipayan\\desktop\\salaries.csv";         bufferedreader br= new bufferedreader(new filereader(csv));         string line="";          try {             br.readline();              while((line = br.readline())!=null)             {                 string[] f=line.split(",");                 system.out.println(" salary ="+f[2]);             }         } catch (ioexception e) {             // todo auto-generated catch block             e.printstacktrace();         }     } }

i think should use map here or may 

list<integer, string>

in case of map

 map<integer,string>

where key salary , string whole complete row. let me write code you.

 map<integer,string> datamap = new hashmap<integer,string>();  string row = br.readline();  string columns[]=row.split(","); // columns[2] has salary  datamap.add(integer.valueof(columns[2]),row);

use bubble sort saw content or customer compare class sort map. check possible sort functions of collection api.

you can use list<integer,string>

sort respect integer, keep placing elements on actual positions , re-generate file.

edit: can use tree map since sorts data. use treemap of integer key , string value. put values in , iterate on it, that's all!


Comments

Post a Comment

Popular posts from this blog

java - Custom OutputStreamAppender not run: LOGBACK: No context given for <MYAPPENDER> -

-
i wish write custom appender on basis of outputstreamappender . wrote following class package tests; import java.io.ioexception; import java.io.outputstream; import ch.qos.logback.core.outputstreamappender; public class myappender<e> extends outputstreamappender<e> { public myappender() { system.out.println("myappender created"); setoutputstream(new outputstream() { @override public void write(int b) throws ioexception { throw new unsupportedoperationexception(); } }); } } then wrote following runner: package tests; import org.slf4j.loggerfactory; import ch.qos.logback.classic.logger; public class runner { private static final logger log = (logger) loggerfactory.getlogger(runner.class); public static void main(string[] args) { //log.addappender(new myappender<iloggingevent>()); log.info("hello world"); } } finall...
Read more

java - UML - How would you draw a try catch in a sequence diagram? -

-
Image
is there standard way of drawing try catch sequence diagrams? i've made attempt based on this feel end result doesn't feel right. code diagram based around: public static void save () { try { filehandle filehandle = gdx.files.external(file); filehandle.writestring(boolean.tostring(constantshandler.soundenabled)+"\n", false); (int = 0; < 5; i++) { filehandle.writestring(integer.tostring(constantshandler.highscores[i])+"\n", true); } } catch (throwable e) { } } my attempt note: know still need add loop. that's ok. fragments meant show conditional control flow in sequence diagram. superstructures puts limitations on use of fragments (see pp. 467 of ss2.1.1). should use critical region try part above. , option catch . however, keep telling can take quite freedom in using uml. it's language , such changes in life time. long reader ge...
Read more

c++ - No viable overloaded operator for references a map -

-
i trying use map can make tag names reference number. when try , use it, in code error (6 in total every time reference map): src/main.cpp:25:45: error: no viable overloaded operator[] type 'std::map<std::string, std::string>' const char* idcs = node.child_value(tagmap[3]); this code: #include "pugi/pugixml.hpp" #include <iostream> #include <string> #include <map> int main() { pugi::xml_document doca, docb; std::map<std::string, pugi::xml_node> mapa, mapb; std::map<std::string, std::string> tagmap {{"1", "data"}, {"2", "entry"}, {"3", "id"}, {"4", "content"}}; if (!doca.load_file("a.xml") || !docb.load_file("b.xml")) { std::cout << "can't find input files"; return 1; } (auto& node: doca.child(tagmap[1]).children(tagmap[2])) { co...
Read more