如何使用Spring Validator以编程方式验证Map<String、String>

import org.springframework.validation.Errors;
import org.springframework.validation.ValidationUtils;
import org.springframework.validation.Validator;

public class MapValidator implements Validator {

    @Override
    public boolean supports(Class<?> clazz) {
        return Map.class.isAssignableFrom(clazz);
    }

    @Override
    public void validate(Object target, Errors errors) {
        Map<String, String> map = (Map<String, String>) target;

        // 使用ValidationUtils进行验证
        ValidationUtils.rejectIfEmptyOrWhitespace(errors, "key1", "key1.required", "Key1 is required.");
        ValidationUtils.rejectIfEmptyOrWhitespace(errors, "key2", "key2.required", "Key2 is required.");

        // 自定义验证逻辑
        if (map.containsKey("key1") && map.get("key1").length() < 5) {
            errors.rejectValue("key1", "key1.minlength", "Key1 length must be at least 5 characters.");
        }
    }
}

import org.springframework.validation.BeanPropertyBindingResult;
import org.springframework.validation.Errors;
import org.springframework.validation.ValidationUtils;

public class Main {

    public static void main(String[] args) {
        Map<String, String> map = new HashMap<>();
        map.put("key1", "value1");
        map.put("key2", "value2");

        Validator validator = new MapValidator();
        Errors errors = new BeanPropertyBindingResult(map, "map");

        // 使用验证器进行验证
        ValidationUtils.invokeValidator(validator, map, errors);

        if (errors.hasErrors()) {
            // 处理验证错误
            System.out.println("Validation failed. Errors: " + errors.getAllErrors());
        } else {
            // 验证通过
            System.out.println("Validation passed.");
        }
    }
}