//演示HashMap類和TreeMap類的用法
import java.util.*;
class Mortgage{

	private double annualInterestRate;//年利率
	private int numberOfYears;//貸款年數
	private double loanAmount;//貸款數額

	public Mortgage(){
		this(6.0,10,10000);
	}
	public Mortgage(double interestRate,int years,double loan){
		this.annualInterestRate = interestRate;
		this.numberOfYears = years;
		this.loanAmount = loan;
	}

	public double getAnnualInterestRate(){//獲取年利率
		return annualInterestRate;
	}
	public void setAnnualInterestRate(double interestRate){//設置年利率
		this.annualInterestRate = interestRate;
	}

	public int getNumberOfYears(){
		return numberOfYears;
	}
	public void setNumberOfYears(int years){
		this.numberOfYears = years;
	}

	public double getLoanAmount(){
		return loanAmount;
	}
	public void setLoanAmount(double loan){
		this.loanAmount = loan;
	}

	//計算月還款額
	public double monthlyPayment(){
		double monthlyInterestRate = annualInterestRate/1200;
		return loanAmount * monthlyInterestRate/ (1 -
			(Math.pow(1/(1 + monthlyInterestRate),numberOfYears * 12)));
	}
	//計算總還款額
	public double totalPayment(){
		return monthlyPayment() * 12 * numberOfYears;
	}
}

public class UsingMap {
  public static void main(String args[]) {
	  //創建哈希集
	  HashMap hashMap = new  HashMap();
	  hashMap.put("張智",new Mortgage(6.5,10,20000));
	  hashMap.put("李奇",new Mortgage(6.5,10,30000));
	  hashMap.put("姜森",new Mortgage(6.5,15,30000));
	  hashMap.put("鄭國慶",new Mortgage(6.5,15,10000));

	  //顯示王五的貸款數額
	  System.out.println("張智的貸款數額是" +
		  ((Mortgage)(hashMap.get("張智"))).getLoanAmount());
	  //為哈希集創建數集
	  TreeMap treeMap = new  TreeMap(hashMap);

	  Set entrySet = treeMap.entrySet();
	  Iterator iterator = entrySet.iterator();

	  System.out.println("\n以鍵的升序順序顯示映射"); 
	  while(iterator.hasNext()){
		  System.out.println(iterator.next());
	  }
  }
}