JsonPath is to JSON what XPATH is to XML, a simple way to extract parts of a given document. JsonPath is available in many programming languages such as Javascript, Python and PHP. Now also in Java!

News

2012-04-16 Released 0.8.1 bug fixes, improved docs, general improvements

2012-03-08 Released 0.8.0 bug fixes, Filter builder, Json model, POJO mapping (optional) and compliance improvements.

2012-02-09 Released 0.5.6 including bug fixes and performance improvements.

Given

{ "store": {
    "book": [ 
      { "category": "reference",
        "author": "Nigel Rees",
        "title": "Sayings of the Century",
        "price": 8.95
      },
      { "category": "fiction",
        "author": "Evelyn Waugh",
        "title": "Sword of Honour",
        "price": 12.99,
        "isbn": "0-553-21311-3"
      }
    ],
    "bicycle": {
      "color": "red",
      "price": 19.95
    }
  }
}

Read

All authors:

List<String> authors = JsonPath.read(json, "$.store.book[*].author");

Author of first book in store:

String author = JsonPath.read(json, "$.store.book[1].author");

All books with category = "reference"

List<Object> books = JsonPath.read(json, "$.store.book[?(@.category == 'reference')]");

List<Object> books = JsonPath.read(json, "$.store.book[?]", filter(where("category").is("reference")));

All books that cost more than 10 USD

List<Object> books = JsonPath.read(json, "$.store.book[?(@.price > 10)]");

List<Object> books = JsonPath.read(json, "$.store.book[?]", filter(where("price").gt(10)));

All books that have isbn

List<Object> books = JsonPath.read(json, "$.store.book[?(@.isbn)]");

List<Object> books = JsonPath.read(json, "$.store.book[?]", filter(where("isbn").exists(true)));

Chained filters

Filter filter = Filter.filter(Criteria.where("isbn").exists(true).and("category").in("fiction", "reference"))

List<Object> books = JsonPath.read(json, "$.store.book[?]", filter);

Custom filters

Filter myFilter = new Filter.FilterAdapter<Map<String, Object>>(){
                @Override
                public boolean accept(Map<String, Object> map) {
                     return map.containsKey("isbn");   
                }
            };

List<Object> books = JsonPath.read(json, "$.store.book[?]", myFilter);

All prices in the document

List<Double> prices = JsonPath.read(json, "$..price");

Compiled path

You can pre compile a path and use it multiple times

JsonPath path = JsonPath.compile("$.store.book[*]");

List<Object> books = path.read(json);

Assert

Asserts are made with Hamcrest matchers

JsonAssert.with(json).assertThat("$.store.bicycle.color", Matchers.equalTo("red"))
          .assertThat("$.store.bicycle.price", Matchers.equalTo(19.95D));

Add some static imports and you get this

with(json).assertThat("$.store.bicycle.color", equalTo("red"))
          .assertThat("$.store.bicycle.price", equalTo(19.95D));

The Hamcrest library contains a lot of different matchers and they can often be nested.

with(json).assertThat("$..author", hasItems("Nigel Rees", "Evelyn Waugh"))
          .assertThat("$..author", is(collectionWithSize(equalTo(2))));

with(json).assertThat("$.store.book[?(@.category == 'x')]", emptyCollection());

If you don't find the matcher you need, roll your own.

Download

Json-path is available at Maven Central

<dependency>
    <groupId>com.jayway.jsonpath</groupId>
    <artifactId>json-path</artifactId>
    <version>0.8.1</version>
</dependency>

<dependency>
    <groupId>com.jayway.jsonpath</groupId>
    <artifactId>json-path-assert</artifactId>
    <version>0.8.1</version>
    <scope>test</test>
</dependency>