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public class GRQ  // save as GRQ.java
  {
    public static void main(String [] args) throws Exception
      {
        BankAcc.getNumAccs();
        BankAcc owen = new BankAcc();
        owen.deposit(5000.75);
        owen.getBalance();
        BankAcc.getNumAccs();
        System.out.println("Your account number is " + owen.getAccNo());

        BankAcc feit = new BankAcc(5000.75);
        System.out.println("Your account number is " + feit.getAccNo());        
        feit.spend(3000.50);
        feit.getBalance();
        BankAcc.getNumAccs();
      }
  }


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public class BankAcc  // save as BankAcc.java
  {
    // ------------- class constants ------------------------------
    private final static int SAVINGS_NO = 5000;
    private final static int CHQKING_NO = 0;
    private final static int MAX_ACCOUNTS = 10000;

    // ------------- instance data fields -------------------------
    private double balance;
    private int accountNumber;

    // ------------- static data fields ---------------------------
    private static int numAccs = 0;
    private static int [] accNos = new int[MAX_ACCOUNTS];

    // ------------- static operations ----------------------------
    static 
      { for (int i = 0; i<accNos.length; i++)
          accNos[i] = CHQKING_NO + 1 + i;
      }

    // ------------- instance methods -----------------------------
    public double getBalance() 
      { return balance; }
    public void setBalance( double amt )
      { balance = amt; }
    public int getAccNo()
      { return accountNumber; }

    public void spend( double amt )
      { balance -= amt; 
        System.out.println("you spent " + amt);
      }
    public void deposit( double amt )
      { balance += amt; 
        System.out.println("you deposited " + amt);}

    // ------------- static class methods -------------------------
    public static void getNumAccs()
      { System.out.println(numAccs + " accounts have been created"); }

    // ------------- class constructors --------------------------- 
    public BankAcc( double amt )
      { setBalance(amt); 
        numAccs++;
        accountNumber = SAVINGS_NO + numAccs;
      }
    public BankAcc()
      { this(0.0); }  
  }



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import java.io.*; 

public class stringy  // save as stringy.java
  { 
    public static void main(String [] args) throws Exception 
      { 
        final int MAX_SIZE = 10; 
        InputStreamReader isr   = new InputStreamReader ( System.in ); 
        BufferedReader inComing = new BufferedReader ( isr ); 
        // "true" in PrintWriter determines whether to "flush" the stream 
        PrintWriter screen      = new PrintWriter ( System.out , true ); 
        // "true" in FileOutputStream determines whether to append the text 
        FileOutputStream fos    = new FileOutputStream ( "a.txt" , true ); 
        PrintWriter filer       = new PrintWriter ( fos ); 
      
        String [] a = new String[MAX_SIZE]; 
        String temp = ""; 
        int count = 0; 
        int i = 0; 

        do 
          { 
            screen.println ( "Enter a string." ); 
            temp = inComing.readLine(); 
            if ( !temp.equals("") ) 
              a[i] = new String( temp ); 
            count = i++; 
          } while ( !temp.equals("") && (i < a.length) ); 

        for (i=0; i<count; i++) 
          screen.println(a[i]);  // make this filer.println to write to the file.

        filer.close(); 
      } 
  } 



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