Java集合处理：如何正确获取并返回多条记录响应

public BankDetails getRes(List<Banks> res){
    BankExcel bank = new BankExcel();
    bank.setName(res.listIterator().next.getName()); // 潜在的编译错误和逻辑错误
    bank.setAddress(res.listIterator().next.getAddress()); // 潜在的编译错误和逻辑错误
    BankParent ban = bank; // 'ban' 对象未被使用
    BankDetails bankDetails = new BankDetails();
    bankDetails.setVal(Collections.singletonList(bankDetails)); // 创建循环引用，且未包含实际的银行数据
    // 缺少 return 语句
}

// 代表输入列表中的单个银行信息
class Banks {
    private String name;
    private String address;

    // 构造函数
    public Banks() {}
    public Banks(String name, String address) {
        this.name = name;
        this.address = address;
    }

    // Getter和Setter方法
    public String getName() { return name; }
    public void setName(String name) { this.name = name; }
    public String getAddress() { return address; }
    public void setAddress(String address) { this.address = address; }
}

// 代表经过处理后的银行数据，通常是业务逻辑层使用的实体或DTO
class BankExcel {
    private String name;
    private String address;

    // 构造函数
    public BankExcel() {}
    public BankExcel(String name, String address) {
        this.name = name;
        this.address = address;
    }

    // Getter和Setter方法
    public String getName() { return name; }
    public void setName(String name) { this.name = name; }
    public String getAddress() { return address; }
    public void setAddress(String address) { this.address = address; }
}

// 代表最终的API响应对象，它应该包含一个BankExcel对象的列表
class BankDetails {
    private List<BankExcel> banks; // 存储多个BankExcel对象

    // 构造函数
    public BankDetails() {}
    public BankDetails(List<BankExcel> banks) {
        this.banks = banks;
    }

    // Getter和Setter方法
    public List<BankExcel> getBanks() { return banks; }
    public void setBanks(List<BankExcel> banks) { this.banks = banks; }
}

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

public class BankProcessor {

    /**
     * 处理银行列表，将其转换为BankExcel对象列表，并封装在BankDetails响应对象中。
     *
     * @param inputBanks 包含多个Banks对象的输入列表
     * @return 包含所有处理后BankExcel对象的BankDetails响应对象
     */
    public BankDetails getRes(List<Banks> inputBanks) {
        // 1. 对输入列表进行空值或空检查，确保程序的健壮性
        if (inputBanks == null || inputBanks.isEmpty()) {
            // 如果输入为空，返回一个包含空列表的BankDetails对象，避免NPE
            BankDetails bankDetails = new BankDetails();
            bankDetails.setBanks(new ArrayList<>()); // 或 Collections.emptyList()
            return bankDetails;
        }

        // 2. 创建一个列表来收集所有处理后的BankExcel对象
        List<BankExcel> processedBankExcels = new ArrayList<>();

        // 3. 使用for-each循环遍历输入列表中的每一个Banks对象
        for (Banks bank : inputBanks) {
            // 4. 为每个Banks对象创建一个新的BankExcel对象
            BankExcel bankExcel = new BankExcel();
            // 5. 将Banks对象的数据映射到BankExcel对象
            bankExcel.setName(bank.getName());
            bankExcel.setAddress(bank.getAddress());
            // 6. 将处理后的BankExcel对象添加到收集列表中
            processedBankExcels.add(bankExcel);
        }

        // 7. 创建最终的BankDetails响应对象
        BankDetails bankDetails = new BankDetails();
        // 8. 将收集到的BankExcel列表设置到BankDetails对象中
        bankDetails.setBanks(processedBankExcels);

        // 9. 返回完整的BankDetails响应对象
        return bankDetails;
    }

    // 示例用法（可选，用于测试）
    public static void main(String[] args) {
        BankProcessor processor = new BankProcessor();

        // 模拟输入数据
        List<Banks> banksInput = new ArrayList<>();
        banksInput.add(new Banks("HSBC", "London"));
        banksInput.add(new Banks("RBL", "Mumbai"));
        banksInput.add(new Banks("BOC", "Beijing"));

        // 调用处理方法
        BankDetails response = processor.getRes(banksInput);

        // 打印结果
        System.out.println("Processed Banks:");
        if (response != null && response.getBanks() != null) {
            for (BankExcel bank : response.getBanks()) {
                System.out.println("  Name: " + bank.getName() + ", Address: " + bank.getAddress());
            }
        } else {
            System.out.println("No banks processed or response is null.");
        }

        // 测试空输入
        System.out.println("\nTesting with empty input:");
        BankDetails emptyResponse = processor.getRes(new ArrayList<>());
        System.out.println("Empty response banks count: " + (emptyResponse != null ? emptyResponse.getBanks().size() : "null"));

        // 测试null输入
        System.out.println("\nTesting with null input:");
        BankDetails nullResponse = processor.getRes(null);
        System.out.println("Null response banks count: " + (nullResponse != null ? nullResponse.getBanks().size() : "null"));
    }
}