创建一个Arraylist,然后向里面添加一个Loan对象，并用toString（）显示列表中的元素

好的，以下是用Java语言实现的代码：

首先需要定义一个Loan类，代码如下：

public class Loan {
    private String borrower;
    private double amount;

    public Loan(String borrower, double amount) {
        this.borrower = borrower;
        this.amount = amount;
    }

    public String getBorrower() {
        return borrower;
    }

    public void setBorrower(String borrower) {
        this.borrower = borrower;
    }

    public double getAmount() {
        return amount;
    }

    public void setAmount(double amount) {
        this.amount = amount;
    }

    @Override
    public String toString() {
        return "Loan{" +
                "borrower='" + borrower + '\'' +
                ", amount=" + amount +
                '}';
    }
}

然后创建一个ArrayList对象，往里面添加Loan对象，并用toString()方法显示列表中的元素：

import java.util.ArrayList;

public class Test {
    public static void main(String[] args) {
        ArrayList<Loan> loanList = new ArrayList<>();
        loanList.add(new Loan("Alice", 1000.0));
        loanList.add(new Loan("Bob", 2000.0));
        loanList.add(new Loan("Charlie", 3000.0));

        for (Loan loan : loanList) {
            System.out.println(loan.toString());
        }
    }
}

输出结果为：

Loan{borrower='Alice', amount=1000.0}
Loan{borrower='Bob', amount=2000.0}
Loan{borrower='Charlie', amount=3000.0}

希望能够帮到您！