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Reading from CSV file and create object

I'm a complete beginner to Java and I have been given an exercise where I have to read data from a CSV file and then create an object for each line of the file as the program reads the data from the file.
Here is part of the CSV file:
1,Jay, Walker,91 Boland Drive,BAGOTVILLE,NSW,2477
2,Mel, Lowe,45 Ocean Drive,MILLERS POINT,NSW,2000
3,Hugh, Manatee,32 Edgecliff Road,REDFERN,NSW,2016
4,Elizabeth, Turner,93 Webb Road,MOUNT HUTTON,NSW,2290
and so on ...
Here is my code that reads data from the CSV file:
import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;
public class Client_19918424 {
public static void main(String[] args) throws FileNotFoundException {
File inFile = new File("clients.txt");
Scanner inputFile = new Scanner(inFile);
String str;
String[] tokens;
while (inputFile.hasNext()) {
str = inputFile.nextLine(); // read a line of text from the file
tokens = str.split(","); // split the line using commas as delimiter
System.out.println("Client ID: " + tokens[0]);
System.out.println("Client First Name: " + tokens[1]);
System.out.println("Client Sur Name: " + tokens[2]);
System.out.println("Street Address: " + tokens[3]);
System.out.println("Suburb: " + tokens[4]);
System.out.println("State: " + tokens[5]);
System.out.println("Postcode:" + tokens[6]);
System.out.println( );
} // end while
}
}
this is my Client class (have constructor):
public class Client {
private int clientID;
private String firstName;
private String surName;
private String street;
private String suburb;
private String state;
private int postcode;
// constructor
public Client (int ID, String fName, String sName, String str, String sb, String sta, int pCode) {
clientID = ID;
firstName = fName;
surName = sName;
street = str;
suburb = sb;
state = sta;
postcode = pCode;
}
However I don't know how to create a Client object for each line of text file as the program reads data from file.
like for the first line make something like this:
Client client1 = new Client(1, "Jay", "Walker", "91 Boland Drive", "BAGOTVILLE", "NSW", 2477);
And then add it to array:
Client[0] = client1;
can someone help me to solve this question, im really appreciate.

You are almost there.
All that's left to do is to map each token that is already printed to the corresponding fields in the Client class. Since token[0] doesn't really tell what value it holds you could do it in three ways:
while (inputFile.hasNext()) {
str = inputFile.nextLine();
tokens = str.split(",");
// Because tokens[0] is of type String but clientID is of type int,
// we need to parse it and get the integer representation.
int clientID = Integer.parseInt(tokens[0]);
// Both of type String, no parsing required.
String firstName = tokens[1];
String surName = tokens[2];
String street = tokens[3];
String suburb = tokens[4];
String state = tokens[5];
int postcode = Integer.parseInt(tokens[6]);
// Then all that's left to do is to create a new object of `Client` type
// and pass all the gathered information.
Client client = new Client(clientID, firstName, surName, street, suburb, state, postcode);
System.out.println(client + "\n");
}
At this moment if we try to print the client (last line) we will get something like this: com.example.demo.Client#30a3107a. That's because we didn't tell how we want our object to be displayed. For that toString() method in Client class has to be overriden like so:
#Override
public String toString() {
return "Client ID: " + clientID + "\n" + "Client First Name: " + firstName + "\n"
+ "Client Sur Name: " + surName + "\n" + "Street Address: " + street + "\n"
+ "Suburb: " + suburb + "\n" + "State: " + state + "\n" + "Postcode: " + postcode;
}
It will give the exact output that is in your example.
It is achievable to create the class by passing those tokens directly as well, without the creation of temporary variables:
Client client = new Client(Integer.parseInt(tokens[0]), tokens[1], tokens[2], tokens[3], tokens[4], tokens[5], Integer.parseInt(tokens[6]));
This case brings us to the third solution with setters and getters.
The variables that describe the Client are already defined, it is possible to pass them to assemble the perfect object, but it is not possible to retrieve them. Instead of setting the variables directly in the constructor, we can create a special method that will do the job, for instance:
// Other fields omitted
private int clientID;
// The empty constructor required for later usage,
// since right now, we can't create the object without specifying every property.
public Client() {
}
// This method does exactly the same thing that was done before but
// in the constructor directly
public void setClientID(int clientID) {
this.clientID = clientID;
}
// This method will assist in retrieving the set data from above.
public int getClientID() {
return clientID;
}
And then the while loop would look like this instead:
Client client = new Client();
client.setClientID(Integer.parseInt(tokens[0]));
client.setFirstName(tokens[1]);
client.setSurName(tokens[2]);
client.setStreet(tokens[3]);
client.setSuburb(tokens[4]);
client.setState(tokens[5]);
client.setPostcode(Integer.parseInt(tokens[6]));
And to get those values:
System.out.println("Client ID: " + client.getClientID());
Or you could use the constructor with the fields to create the client, add getters in the class, omit both setters, and the empty constructor if the creation of the client should only be possible with all the fields present.

Why do I get, and how do I solve this "String to object of type <objecttype>" error

I am (being an absolute beginner), trying to create a simple tool, that creates some objects and links them.
The objects are:
Customers
Licenses (2 types, extends class)
The idea is to use (one of) the customer company name when creating a license, so the license is linked to a customer.
I use ArrayLists to store the data.
I tried to use the getter for Customer cCompany, but when I try to actually create a new license object, I get errors about incompatible types (String to object of type customer)
How can I fix that error?
Any help is highly appreciated, but please explain well, me being an absolute beginner. I probably overcomplicate stuff....
Some code extracts:
From Main:
public class Main {
public static void main(String[] args) {
//Create customers
List <Customer> customers = new ArrayList <> (10);
customers.add(new Customer("TestCompany","John Doe",1234567890,"John#testcompany.com"));
....
//Create Elvis licenses (based on superclass License)
List <ElvisLicense> ellicenses = new ArrayList <> (10);
ellicenses.add(new ElvisLicense("TestCompany","VendorA",1234,"1234-A","Solutions Server gold","1234-dtbk-87654-nlof",10, true , true));
Class: Customer:
class Customer {
String cCompany;
private String cName;
private int cPhone;
private String cEmail;
public Customer( String cCompany, String cName,int cPhone, String cEmail)
{
this.cCompany = cCompany;
this.cName = cName;
this.cPhone = cPhone;
this.cEmail = cEmail;
}
//This getter should be used to link the license to the customer (Done in License.java)
public String getcCompany() {
return cCompany;
}
Class License (Superclass)
class License {
// Used no modifier to set access for Class/Package and Subclass inside the package
Customer licenseCompany;
String lVendor;
int lContractNumber;
String lCertificateNumber;
String lProductName;
String lLicenseKey;
int lNumberOfSeats;
public License(Customer cCompany, String lVendor, int lContractNumber, String lCertificateNumber,
String lProductName, String lLicenseKey, int lNumberOfSeats)
{
licenseCompany = cCompany;
this.lVendor = lVendor;
this.lVendor = lVendor;
this.lContractNumber = lContractNumber;
this.lCertificateNumber = lCertificateNumber;
this.lProductName = lProductName;
this.lLicenseKey = lLicenseKey;
this.lNumberOfSeats = lNumberOfSeats;
}
public Customer getLicenseCompany() {
return licenseCompany;
}
public void setLicenseCompany(Customer licenseCompany) {
this.licenseCompany = licenseCompany;
}
//preparations to allow for example printing the content of an arraylist element
#Override
public String toString(){
return "Customer name " + getLicenseCompany() + "\n" + "Vendor name " + getlVendor() + "\n" + "Contract number: " + getlContractNumber() + "\n"
+ "Certificate number: " + getlCertificateNumber() + "\n" +
"Product name " + getlProductName() + "\n" + "Licence key: " + getlLicenseKey() + "\n"
+ "Number of seats: " + getlNumberOfSeats();
}
}
And the extended class:
public class ElvisLicense extends License{
private boolean elIsBundle;
private boolean elIsSubscription;
public ElvisLicense(
Customer licenseCompany,
String lVendor,
int lContractNumber,
String lCertificateNumber,
String lProductName,
String lLicenseKey,
int lNumberOfSeats,
boolean elIsBundle,
boolean elIsSubscription
)
{
super(
licenseCompany,
lVendor,
lContractNumber,
lCertificateNumber,
lProductName,
lLicenseKey,
lNumberOfSeats);
this.elIsBundle = elIsBundle;
this.elIsSubscription = elIsSubscription;
}
.....
#Override
public String toString(){
return "Customer name " + licenseCompany + "\n"
+ "Vendor name " + lVendor + "\n"
+ "Contract number: " + lContractNumber + "\n"
+ "Certificate number: " + lCertificateNumber + "\n"
+ "Product name " + lProductName + "\n"
+ "Licence key: " + lLicenseKey + "\n"
+ "Number of seats: " + lNumberOfSeats + "\n"
+ "Number of seats: " + elIsBundle + "\n"
+ "Number of seats: " + elIsSubscription;
}
}
I expect that the Customername is used when creating a new license.

Below line is wrong.
ellicenses.add(new ElvisLicense("TestCompany","VendorA",1234,"1234-A","Solutions Server gold","1234-dtbk-87654-nlof",10, true , true));
As license need customer object an parameter. Instead, you should create customer object first.
ellicenses.add(new ElvisLicense(new Customer("TestCompany","VendorA",1234,"1234-A"),"Solutions Server gold","1234-dtbk-87654-nlof",10, true , true));
for reusing that customer list to avoid create company.
for(Customer customer : customers){
// here you need some way to offer other parameters except customer parameter.
License license = new new ElvisLicense(customer,"Solutions Server gold","1234-dtbk-87654-nlof",10, true , true);
ellicenses.add(license);
}

What you need to do is to use one of the Customer objects you have already created when creating the ElvisLicense object. To more easily find that customer by name I suggest you store them in a map instead of a list with the name as a key.
Map<String, Customer> customerMap = new HashMap<>();
Customer customer = new Customer("TestCompany","John Doe",1234567890,"John#testcompany.com"));
customerMap.put(customer.getcCompany(), customer);
so when creating the license you look up the customer
List <ElvisLicense> ellicenses = new ArrayList <> (10);
Customer customer = customerMap.get("TestCompany");
if (customer != null) {
ElvisLicense license = new ElvisLicense(customer,"VendorA",1234,"1234-A","Solutions Server gold","1234-dtbk-87654-nlof",10, true , true));
ellicenses.add(license);
} else {
//If the customer isn't found you need some kind of error handling, better than below :)
System.out.println("Can't create a license, no customer found");
}

accessing list elements in java

I created a linkedlist object as follows
importBuffer = new BufferedReader(new FileReader(importcsvFile));
while ((line = importBuffer.readLine()) != null) {
// use comma as separator
String[] importedFile = line.split(cvsSplitBy); //cap,comune,provincia,stato
System.out.println("Codice Azienda " + importedFile[0] + " , Codice Cliente=" + importedFile[1] + " , Regione Sociale=" + importedFile[2] + " , Indrizzo=" + importedFile[3] + " , comune=" + importedFile[4] + " , provincia=" + importedFile[5] + " , stato=" + importedFile[6] +"]");
counter++;
PublicDefinition.importList.add(importBuffer.toString());
List customers = select.select(importedFile[0],importedFile[1], importedFile[3]);
if(!customers.isEmpty())
{
System.out.println("selected Customer : " + customers.size());
buffureList = customers;
Object a=List.class.cast(customers);
PublicDefinition.testingList.add(buffureList.toString());
System.out.println("selected Customer : " + PublicDefinition.importList.get(0));
System.out.println("selected Customer : " + PublicDefinition.testingList.getFirst());
updateCustomer = customers;
if(customers.get(0)==importedFile[0])
System.out.println("Matched Codice Azienda");
select.updateTable(importedFile[1], importedFile[3], "10.34", "11.40"); //String CodiceCliente, String indrizzo, String latitude, String longitute
}
}
when I try to access the elements for the linkedlist using
System.out.println("selected Customer : " + PublicDefinition.importList.get(0));
I got the output:
selected Customer : java.io.BufferedReader#420dc55b
I think this is the memory reference, but I want to retrieve the value of the linkedlist
my select function is:
public List<Customer> select(String codiceAzienda, String codiceCliente, String indrizzo) {
return jdbcTemplate.query(
"SELECT * FROM customers WHERE CodiceAzienda= ?",
new Object[] { codiceAzienda},
(rs, rowNum) -> new Customer(rs.getLong("id"),
rs.getString("CodiceAzienda"), rs.getString("Indrizzo"), rs.getString("codice_cliente"), rs.getString("Indrizzo")));
}

You added the toString() value of the importBuffer object, not the actual contents. The default toString() implementation (which every object inherits from... Object) returns ClassName#HashCode. So your output isn't wrong, but your input is.
See Object.toString() in the javadoc

Go ahead and perform:
PublicDefinition.importList.add(importBuffer.readLine());
Instead of :
PublicDefinition.importList.add(importBuffer.toString());
Since you are trying to output the contents of the buffered reader instead of the ClassName#Hashcode contents.

Replace
PublicDefinition.importList.add(importBuffer.toString());
with
PublicDefinition.importList.add(importedFile);
You are accidentally adding the string representation of BufferReader object, not the list of import files which sounds like your intention.

java result set only writing one line instead of all selected into .csv

I have a java function that is meant to take strings from jlist called "readyList" and pulling data from mysql workbench tables with the intent to write a line for each string in a .csv file. With the current code it sucessfully pulls the data one at a time like i intended but it only writes the last line instead of all the lines. I want to have all the lines written in the .csv file. Please help!
int[] selectedIx = readyList.getSelectedIndices();
for (int i = 0; i < selectedIx.length; i++) {
// while (i < selectedIx.length) {
Object sel = readyList.getModel().getElementAt(selectedIx[i]);
Statement s1 = DBConnect.connection.createStatement();
String selTable01 = "SELECT Sku As s, Qty As q, Orig_Retail As prce, Orig_Sku As orgsk, Store As strcd "
+ "FROM completed_lines WHERE Form_Name = '" + sel + "' AND Warranty = 'true'";
s1.execute(selTable01);
try (ResultSet rs01 = s1.getResultSet()) {
fWriter = new FileWriter("Exports/Transfers/" + /* frmNm.replace(":", "_") */"EBW_" + GtDates.fdate + ".csv", false);
writer = new BufferedWriter(fWriter);
String header = "slip_number,slip_type,out_store,in_store,item_number,quantity,price,comment,to_num";
writer.write(header);
writer.newLine();
while (rs01.next()) {
String strcode = rs01.getString("strcd");
String sku = rs01.getString("s");
String qty = rs01.getString("q");
String price = rs01.getString("prce");
String orgsku = rs01.getString("orgsk");
//System.out.println(frmNm.split("_")[1] + qty + "," + sku + "," + vendor + "," + desc1 + "," + reas + "," + descdmg + "," + orgR + "," + nwsku + "," + desc2 + "," + qtyI);
String line = ""+","+"out"+","+strcode+","+"RTV"+","+sku+","+qty+","+price+","+"EBW"+","+orgsku;
writer.write(line);
writer.newLine();
}
}
// JOptionPane.showMessageDialog(frame, "All Data from Selected Forms has been Exported");
}
// FormCompelted();
writer.close();
}
}

A few issues with this code. The reason you're only getting the last result is because of this line:
fWriter = new FileWriter("Exports/Transfers/" + /* frmNm.replace(":", "_") */"EBW_" + GtDates.fdate + ".csv", false);
This line is inside your loop. The false as the last parameter tells FileWriter not to append. In other words, a false means overwrite the file if it exists. Since this is in your loop, each result overwrites the file that the last result created. You should create the FileWriter outside of your loop, probably in a try with resources. That will allow you to remove your writer.close() call, which should have been in a finally block anyway.
Not related to your original question but something you should be aware of: You're creating a new Statement with each loop iteration. This can be an expensive operation. You should use a PreparedStatement instead. Create it outside your loop and then just set the parameter and execute it inside the loop. It also implements AutoCloseable, so you can create it in a try with resources too, probably the same one you create your FileWriter in.

After extracting data from html using a for loop, how do I insert one by one into a database?

I have extracted multiple data from an HTML using Jsoup and now I am trying to insert one by one into a derby db using JDBC on netbeans.
Here is my code:
public String nameOf() {
String nameStr = null;
String nameResults = "";
for(int j=100;j<=110;j++) {
refNum = j;
//System.out.println("Reference Number: " + refNum);
try {
//crawl and parse HTML from definition and causes page
Document docDandC = Jsoup.connect("http://www.abcd.edu/encylopedia/article/000" + refNum + ".htm").get();
// scrape name data
Elements name = docDandC.select("title");
nameStr = name.get(0).text();
//System.out.println(nameStr);
nameResults += nameStr + " ";
} catch (Exception e) {
//System.out.println("Reference number " + refNum + " does not exist.");
}
}
return nameResults;
So this method takes the names of diseases from 10 different HTMLs. What I am trying to do is to insert one name at a time to a derby db that I have created using JDBC. I have everything set up and all I have left to do is to insert each name in the corresponding name field of a table named DISEASE (which has fields: id, name, etc).
nameResults += nameStr + " ";
This part worries me as well since some diseases can have multiple words. Maybe I should use a list of some sort?
Please help! Thanks in advance.

Something like:
public List<String> nameOf() {
...
List<String> nameResults = new ArrayList<String>();
...
nameResults.add(nameStr);
...
return nameResults;