java - Read a csv file and separate lines into key and value to put in a hash table -

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so little info program, implemented hash table separate chaining handle collisions.

class tableinput{       object key;      object value;      tableinput(object key, object value){         this.key = key;         this.value = value;     } } abstract class hashtable {     protected tableinput[] tableinput;     protected int size;     hashtable (int size) {         this.size = size;         tableinput = new tableinput[size];         (int = 0; <= size - 1; i++){             tableinput[i] = null;         }     }     abstract int hash(object key);     public abstract void insert(object key, object value);     public abstract object retrieve(object key); } class chainedtableinput extends tableinput {     chainedtableinput(object key, object value){         super(key, value);         this.next = null;     }      chainedtableinput next; }  class chainedhashtable extends hashtable {      chainedhashtable(int size) {         super(size);         // todo auto-generated constructor stub     }     public int hash(object key){         return key.hashcode() % size;      }     public object retrieve(object key){         chainedtableinput p;         p = (chainedtableinput) tableinput[hash(key)];         while(p != null && !p.key.equals(key)){             p = p.next;         }         if (p != null){             return p.value;         }         else {             return null;         }     }      public void insert(object key, object value){         chainedtableinput entry = new chainedtableinput(key, value);         int k = hash(key);         chainedtableinput p = (chainedtableinput) tableinput[k];         if (p == null){             tableinput[k] = entry;             return;         }         while(!p.key.equals(key) && p.next != null){             p = p.next;         }         if (!p.key.equals(key)){             p.next = entry;         }     }     public double distance(object key1, object key2){         final int r = 6373;         double lat1 = double.parsedouble(object);      }     }

now have csv file contains city names, latitude , longitude. need read csv file command line argument , input city names keys in hash table , latitude , longitude value. question how can read csv file , separate data key , value objects put in hash table?

something - 

string csvfilepath = args[0]; bufferedreader br = null; string line = ""; string cvssplitby = ",";  hashtable chainedhashtable = new chainedhashtable(100);  try {         br = new bufferedreader(new filereader(csvfilepath));         while ((line = br.readline()) != null) {                  // use comma separator             string[] cityrow = line.split(cvssplitby);              string cityname = cityrow[0];             double latitude = double.parsedouble(cityrow[1]);             double longitude = double.parsedouble(cityrow[2]);             coordinate coordinate = new cordinate(latitude, longitude);              chainedhashtable.insert(cityname, coordinate);          }      } catch (filenotfoundexception e) {         e.printstacktrace();     } catch (ioexception e) {         e.printstacktrace();     } catch (numberformateexception e) {         e.printstacktrace();     } {         if (br != null) {             try {                 br.close();             } catch (ioexception e) {                 e.printstacktrace();             }         }     }   class coordinate {     double latitude;     double longitude;      coordinate (double latitude, double longitude) {         this.latitude = latitude;         this.longitude = longitude;     }      // other setters , getters }

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