public class Loan {
	private Subscriber borrower;
	private String callNumber;
	private Date returnDate;
	private boolean wasReturned;

	public Loan(Subscriber borrower, String callNumber, Date returnDate, boolean wasReturned) {
		this.borrower = borrower;
		this.callNumber = callNumber;
		this.returnDate = returnDate;
		this.wasReturned = wasReturned;
	}

	public Subscriber getBorrower() {
		return borrower;
	}

	public String getCallNumber() {
		return callNumber;
	}

	public Date getReturnDate() {
		return returnDate;
	}

	public boolean isReturned() {
		return wasReturned;
	}

	public void setReturned(boolean newValue) {
		wasReturned = newValue;
	}
}


import java.util.*;
public class Subscriber {
	String name;
	ArrayList<Loan> loans;

	public Subscriber(String name) {
		this.name = name;
		loans = new ArrayList<Loan>();
	}
	
	public Loan findLoan(String callNumber) {
		for (int i = 0; i < loans.size(); i++) {
			if ( loans.get(i).getCallNumber().equalsIgnoreCase(callNumber) && loans.get(i).isReturned() == false) {
				return loans.get(i);
			} 
		}

		return null;
	}

	public boolean addLoan(String callNumber, Date returnDate, boolean isReturned) {
		if (findLoan(callNumber) != null) {
			return false;
		}
		this.loans.add(new Loan(this, callNumber, returnDate, isReturned);
		return true;
	}

	public ArrayList<Loan> getLoans(LoanFilter filter) {
		ArrayList<Loan> filtered = new ArrayList<Loan>();
		for (int i=0; i < loans.size(); i++ ) {
			if (filter.accept(loans.get(i))) {
				filtered.add(loans.get(i));
			}
		}
		return filtered;
	}
}