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javajsonjsonpath

Check if JSON containts node with value

I have Java application which gets JSON strings like this one

{
    "name": "testName",
    "message": [
        "TestMessage."
    ]
}

What I need is to check if there is a "message" array node which has value of "TestMessage." in any of it's elements.

I have access to com.jway.jsonpath.JsonPath in my code. But it looks that it can only read value of particular node. E.g. like this I will be able to fetch first element of "message" array

JsonPath.read(content, "$.message[0]")

But in this way I will have to fetch all elements of the array into Java and validate them there. Instead I would like to perform this check by JsonPath engine itself.

How can I achive this goal with JsonPath? Is it better to use other library?

Solution

  • You can use the filter operations.

    Filters are logical expressions used to filter arrays. A typical filter would be [?(@.age > 18)] where @ represents the current item being processed. More complex filters can be created with logical operators && and ||. String literals must be enclosed by single or double quotes ([?(@.color == 'blue')] or [?(@.color == "blue")]).

    like this:

     JsonPath.read(json, "$.message[?(@ == "TestMessage.")]");

    more can refer the readme.MD of https://github.com/json-path/JsonPath