java - implement class object and Arraylist -

i new java , have task do.

i have created class (company) looks

 public class company implements serializable {         private string companyname;         private string companycode;         private int shareno;         private double closingrate;          /**          * initializes newly created company object represents      company basic information  in program      */      public company() {         // todo auto-generated constructor stub         this.companyname="";         this.companycode="";         this.shareno=0;         this.closingrate=0.0;      }     /**      * constructs new company object value of passed in parameters      *       * @param companyname - name of company      * @param companycode - 3 letter code of company      * @param shareno- initial value of share issued company      * @param closingrate- price of share rate of previous day      */     public company(string companyname,string companycode,int shareno,double closingrate)     {         this.companyname=companyname;         this.companycode=companycode;         this.shareno=shareno;         this.closingrate=closingrate;     }      /**      * return name of company      *       * @return value of attribute companyname      */     public string getcompanyname()     {         return companyname;     }     /**      * set  name of company new value      *       * @param companyname - new value of name      */     public void setcompanyname(string companyname) {         this.companyname = companyname;     }     /**      * return code of company      *       * @return value of attribute companycode      */public string getcompanycode()      {          return companycode;      }      /**       * set code of company new value       *        * @param companycode - new value of code       */      public void setcompanycode(string companycode) {          this.companycode = companycode;      }      /**       * return shares  of company       *        * @return value of attribute shareno       */      public int getshareno()      {          return shareno;      }      /**       * set shareno of company new value       *        * @param shareno - new value of share number       */      public void setshareno(int shareno) {          this.shareno = shareno;      }      /**       * return closingrate of        *        * @return value of attribute closingrate       */      public double getclosingrate()      {          return closingrate;      }      /**       * set closing rate of company new value referring previous day       *        * @param description - new value of description       */      public void setclosingrate(double closingrate) {          this.closingrate = closingrate;      }       /**       * return string representation of object in presentable format       *        * @return string representation of object       */      public string tostring() //@override      {          return "company code: " + companycode +                   "\ncompany name: " + companyname +                  "\nnumber of shares: " + shareno +                  "\nclosing rate: " +closingrate;      }  } 

and have main program getting required parameters class.

now want store company data name, code, shareno , closing price in arraylist, , write file.

i tried cant understand.

public class companydes {      private arraylist<company> companyinfo;      public companydes()     {         companyingo = new arraylist<company>();     } } 

and got stuck. appreciated!

you need write logic in main(), logic should :

• create company objects
• add company objects arraylist
• read contents arraylist
• write contents file

use following main() code.

public static void main(string[] args) {         try {              list<company> companylist = new arraylist<company>();              company c1 = new company("test company","111",111,89077.0);             companylist.add(c1);             company c2 = new company("non test company","22",222,077.0);             companylist.add(c2);              string content=null;             for(company company:companylist)             content+= company;              file file = new file("d://output.txt");               if (!file.exists()) {                 file.createnewfile();             }              filewriter fw = new filewriter(file.getabsolutefile());             bufferedwriter bw = new bufferedwriter(fw);             bw.write(content);             bw.close();           } catch (ioexception e) {             e.printstacktrace();         }     }