写一个省市级分组的例子，提供数据和输出结果

好的，下面给出一个省市级分组的示例代码，包括数据和输出结果。

示例数据：

List<Address> addressList = new ArrayList<>();
addressList.add(new Address("四川省", "成都市", "锦江区"));
addressList.add(new Address("四川省", "成都市", "武侯区"));
addressList.add(new Address("四川省", "绵阳市", "涪城区"));
addressList.add(new Address("四川省", "绵阳市", "游仙区"));
addressList.add(new Address("贵州省", "贵阳市", "南明区"));
addressList.add(new Address("贵州省", "贵阳市", "云岩区"));
addressList.add(new Address("贵州省", "遵义市", "红花岗区"));
addressList.add(new Address("贵州省", "遵义市", "汇川区"));

示例代码：

public class GroupByDemo {
    public static void main(String[] args) {
        List<Address> addressList = new ArrayList<>();
        addressList.add(new Address("四川省", "成都市", "锦江区"));
        addressList.add(new Address("四川省", "成都市", "武侯区"));
        addressList.add(new Address("四川省", "绵阳市", "涪城区"));
        addressList.add(new Address("四川省", "绵阳市", "游仙区"));
        addressList.add(new Address("贵州省", "贵阳市", "南明区"));
        addressList.add(new Address("贵州省", "贵阳市", "云岩区"));
        addressList.add(new Address("贵州省", "遵义市", "红花岗区"));
        addressList.add(new Address("贵州省", "遵义市", "汇川区"));

        Map<String, Map<String, List<Address>>> groupByProvinceCity = addressList.stream()
                .collect(Collectors.groupingBy(Address::getProvince, Collectors.groupingBy(Address::getCity)));

        groupByProvinceCity.forEach((province, cityMap) -> {
            System.out.println(province + ":");
            cityMap.forEach((city, addressList1) -> {
                System.out.println("\t" + city + ":");
                addressList1.forEach(address -> System.out.println("\t\t" + address.getDistrict()));
            });
        });
    }
}

class Address {
    private String province;
    private String city;
    private String district;

    public Address(String province, String city, String district) {
        this.province = province;
        this.city = city;
        this.district = district;
    }

    public String getProvince() {
        return province;
    }

    public void setProvince(String province) {
        this.province = province;
    }

    public String getCity() {
        return city;
    }

    public void setCity(String city) {
        this.city = city;
    }

    public String getDistrict() {
        return district;
    }

    public void setDistrict(String district) {
        this.district = district;
    }
}

输出结果：

四川省:
	成都市:
		锦江区
		武侯区
	绵阳市:
		涪城区
		游仙区
贵州省:
	贵阳市:
		南明区
		云岩区
	遵义市:
		红花岗区
		汇川区

以上代码中，使用Stream API对Address列表进行分组操作，首先按照省份进行分组，然后在每个省份内部按照城市进行分组。最后遍历分组后的结果，输出省、市、县区三级信息。