hashtable

[kmm1977]

Hi

my task is to read a csv file in the following format and display it in a jtable

for which i want to store it first in a datastructure so that i can filter it depending on the columnnames

csv file looks like:

Anton;12;male;ABC
Martha;13;femal;ZXY

so i read each line and want to store in a hashtable
following code is what i got from java help

but since i must read a row a time in the csv file i cannot enter all the names,ages,sexes, schools details as shown below.

is there a way to , read a line and store it in hashtable or other datastructure with the keys as column names ?

MyTableModel mtm = null;
        String[] columnNames = {"Name",
                                        "Age",
                                        "Sex",
                                        "School"};

        Hashtable model = new Hashtable(columnNames.length);

        Object[][] dataOnCols = {
            {"Anton","Martha"},   //col 0 values
            {12,13},    //col 1 values
            {"male","female"},      //col 2 values
            {"ABC","ZXY"}
        };
        for (int j = 0; j < columnNames.length; j++) {
            String columnName = columnNames[j];
            model.put(columnName, dataOnCols[j]);
        }
        mtm = new MyTableModel(model);

}

[Fubarable]

Simple: create a class whose objects hold each "row" of data.

[Petr]

Hi, You can use List<Map<String, String>> constructions
for example

import java.util.*;

public class ListDataStore {

    public ListDataStore() {
    }

    public List<String> headers() {
        List<String> header = new ArrayList<String>();
        header.add("number");
        header.add("name");
        header.add("aliec");
        header.add("category");
        header.add("deadline");
        header.add("budget");
        return header;
    }

    public List<Map<String, String>> data() {
        List<Map<String, String>> data = new ArrayList<Map<String, String>>();
        for (int i=0;i!=10;++i) {
            Map<String, String> row = new HashMap<String, String>();
            for (String head : headers()) {
                row.put(head, "value");
            }
            data.add(row);
        }
        return data;
    }

    public static void main(String[] args) {
        ListDataStore store = new ListDataStore();
        for (Map<String, String> map : store.data()) {
            for (String header : store.headers()) {
                System.out.print("head : " + header +"; value : " + map.get(header));
            }
            System.out.println();
        }
    }
}

[kmm1977]

hi thanx for your replies

public class MyTable {

	static Hashtable fastTable;
    public ListDataStore() {
    }

    public static void addRow(String Name,String Age,String Sex,String School) {
		
		String[] columnNames = {"Name","Age","Sex","School"};
	
		fastTable = new Hashtable(columnNames.length);
		
		Vector<Object> row = new Vector<Object>();
		row.add(Name); 
		row.add(Age); 
		row.add(Sex); 
		row.add(School); 
		for(int i = 0; i < columnNames.length; i++){
			Object rowVal = row.get(i);
			if(rowVal != null){
				fastTable.put(columnNames[i],rowVal);
			}else{
				fastTable.put(columnNames[i],"");
			}				
		}
}

    public static void main(String[] args) {
        
        
        for (int i = 0 ; i < 5 ; i++) {
            addRow("Martha","13","female","AMC");
        }
        
        for (int i = 0 ; i < 5 ; i++) {
            addRow("Anton","12","Male","XYZ");
        }
        
     // Get Hashtable Enumeration to get key and value
        Enumeration em=fastTable.keys();

        while(em.hasMoreElements())
        {
            //nextElement is used to get key of Hashtable
            String key = (String)em.nextElement();

            //get is used to get value of key in Hashtable
            String value=(String)fastTable.get(key);

            System.out.println("Key :"+key+"  value :"+value);
        }

    }
}

for which i get the following output

Key :Sex value :Male
Key :Name value :Anton
Key :School value :XYZ
Key :Age value :12

Why is it that the first entry is missing ( i am new to java )

regards

[kmm1977]

what i wan to achieve is something like this

-----------------------------
Name Age Sex School
-----------------------------
Anton 12 male ABC
Martha 13 female XYZ

this datastructure must be show up as a JTable in which i must be able to filter based on the columnnames