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POinheritance and polymorphism java
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copied!<p>I have base class, Customer and sub-classes Acc1 up till 3.</p> <p>When I am reading a file to initialize my array of customer objects, they all just show up as empty. As I find out what account type the customer has I assign the variable to the respective object(temp1-3, first1-3). Not quite sure why they remain empty.</p> <p>I am pasting my class definitions for the base and one of the derived classes. The error occurs in the readFile() method when I assign first and temp (Customer class objects_ to first(1/2/3) and temp(1/2/3) (sub classes, Account1, Account2 and Account3).</p> <p>Not sure if the class definitions are wrong as I simply call the super constructor in all of them. tried debugging it but with no success. Help will be appreciated.</p> <pre><code>package lab4; import java.io.*; import java.util.*; public class lab4{ static int count =0; // number of records read or written public static void main(String args[]) throws IOException { Customer[] records = new Customer[30]; for (int j=0; j<30; j++){ records[j] = new Customer(); } menu(records); } public static int readFile(String filename, Customer[] review) throws IOException { Scanner scan = new Scanner (new File (filename)); /*Reading the first record separatly*/ Customer first = new Customer(); Account1 first1= new Account1(); Account2 first2= new Account2(); Account3 first3 = new Account3(); String[] a = scan.nextLine().split("="); first.set_account_id(Integer.parseInt(a[1].trim())); a = scan.nextLine().split("="); first.set_name(a[1].toUpperCase().trim()); a = scan.nextLine().split("="); first.set_address(a[1].trim()); a = scan.nextLine().split("="); first.set_phone_number(a[1].trim()); a = scan.nextLine().split("="); first.set_date_of_birth(a[1].trim()); a = scan.nextLine().split("="); first.set_balance(Double.parseDouble(a[1].trim())); a= scan.nextLine().split("="); first.set_accType(a[1].trim()); if (first.get_accType().equals("Saving")){ first = first1; } else if(first.get_accType().equals("Checking")){ first = first2; } else if(first.get_accType().equals("Fixed")){ first = first3; a = scan.nextLine().split("="); first3.set_intRate(Double.parseDouble(a[1].trim())); } System.out.println(first.get_name()); scan.nextLine();// resets the buffer reader review[0]= first; count = count+1; while (scan.hasNext()&& count>0){ Customer temp = new Customer(); Account1 temp1 = new Account1(); Account2 temp2 = new Account2(); Account3 temp3 = new Account3(); String[] st = scan.nextLine().split("="); for(int i=0;i<count;i++){ if(Integer.parseInt(st[1].trim())== review[i].get_accountid()){ // checking for duplicate records System.out.println("This account id is already in use so the record won't be read"); for (int k=0; k<7; k++) scan.nextLine(); } else break; } temp.set_account_id(Integer.parseInt(st[1].trim())); st = scan.nextLine().split("="); temp.set_name(st[1].toUpperCase().trim()); st = scan.nextLine().split("="); temp.set_address(st[1].trim()); st = scan.nextLine().split("="); temp.set_phone_number(st[1].trim()); st = scan.nextLine().split("="); temp.set_date_of_birth(st[1].trim()); st = scan.nextLine().split("="); temp.set_balance(Double.parseDouble(st[1].trim())); st= scan.nextLine().split("="); temp.set_accType(st[1].trim()); if (temp.get_accType().equals("Saving")){ temp = temp1; } else if(temp.get_accType().equals("Checking")){ temp = temp2; } else if(temp.get_accType().equals("Fixed")){ temp = temp3; st = scan.nextLine().split("="); temp3.set_intRate(Double.parseDouble(a[1].trim())); } if (scan.hasNextLine()){ scan.nextLine(); } int j; for(j=0;j<count;j++){ if (temp.get_name().compareTo(review[j].get_name())<0){ // Putting records in ascending order break; } } count=count+1; for (int k=count;k>j;k--){ review[k]=review[k-1]; } review[j]= temp; if (count>=30){ System.out.println("The number of records read has exceeded the limit and it will stop reading now"); break; } } return count; } } package lab4; import java.io.*; import java.util.*; /** * * @author dawnoflife */ public class Account1 extends Customer { public Account1(){ // Savings Account super(); } public void update(double rate){ // Savings account interest calc double updateBal = (this.get_balance()*( Math.pow((1+rate),31))); // Interest calculated for month of march this.set_balance(updateBal); } } </code></pre>

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