如何使用JsonPath执行子过滤器？

I've read the documentation, and I can't figure out how I perform a sub-filter using JsonPath. Here's an example...

我已经阅读了文档,我无法弄清楚如何使用JsonPath执行子过滤器。这是一个例子......

Given the following JSON, how do I retrieve a list of people with an address in Sydney?

鉴于以下JSON,如何在悉尼检索具有地址的人员列表?

I've tried variations of $.people[?(@.addresses[*].city=="Sydney")] to no avail. e.g.

我尝试过各种各样的$ .people [?(@ .address [*]。city ==“Sydney”)]无济于事。例如

$.people[?(@.addresses[*].city=="Sydney")]
$.people[?(@.addresses.city=="Sydney")]
$.people[?(@..city=="Sydney")]

JSON

{
    "people": [{
            "name": "George",
            "addresses": [{
                "city": "Sydney"
            }]
        },
        {
            "name": "Jane",
            "addresses": [{
                "city": "Brisbane"
            }]
        },
        {
            "name": "Fred",
            "addresses": [{
                    "city": "Perth"
                },
                {
                    "city": "Sydney"
                }
            ]
        }
    ]
}

Preferred Output

{
    "people": [{
            "name": "George",
            "addresses": [{
                "city": "Sydney"
            }]
        },
        {
            "name": "Fred",
            "addresses": [{
                    "city": "Perth"
                },
                {
                    "city": "Sydney"
                }
            ]
        }
    ]
}

I'm using the following Java library: com.jayway.jsonpath:json-path:2.2.0

我正在使用以下Java库:com.jayway.jsonpath:json-path:2.2.0

I'm using http://jsonpath.com/ to test my jsonpath in the browser (maybe that's the problem?).

我正在使用http://jsonpath.com/在浏览器中测试我的jsonpath(也许这就是问题?)。

1 个解决方案

#1

The problem is that @.addresses[*].city is a collection. It is not ANY city of the person and it is not ONLY(each) city of the person.

问题是@ .addresses [*]。city是一个集合。它不是该人的任何城市,也不是该人的唯一城市。

If you are looking for persons with some addresses in Sydney the query should be:

如果您正在寻找在悉尼有一些地址的人,那么查询应该是:

"$.people[?(\"Sydney\" in @.addresses[*].city)]"

“$ .people [?(在@ .addresses [*]。city中的”悉尼“]]”

Example:

String filter = "$.people[?(\"Sydney\" in @.addresses[*].city)]";
ReadContext ctx = JsonPath.parse(json);
List<Map<String, Object>> rez = ctx.read(filter, List.class);

If you are looking for persons with all addresses in Sydney I do not know correct query. It is possible to use Predicate, but it is very complicated code.

如果您正在寻找悉尼所有地址的人,我不知道正确的查询。可以使用Predicate,但代码非常复杂。

Just for information:

仅供参考:

List<Map<String, Object>> rez = JsonPath.parse(json).read(
                "$.people[?]",
                List.class,
                new Predicate() {
            @Override
            public boolean apply(PredicateContext ctx) {
                Map<String, Object> map = ctx.item(Map.class);
                ReadContext readContext = JsonPath.parse(JSONObject.toJSONString(map));
                List<String> allAddresses = readContext.read("$.addresses[*].city");
                List<String> sydneyAddresses = readContext.read("$.addresses[?(@.city=='Sydney')].city");
                return allAddresses.size() == sydneyAddresses.size();
            }
        });

#1