Java JsonPath 实现.zip

Jayway JsonPath ===================== **A Java DSL for reading JSON documents.** [](https://travis-ci.org/json-path/JsonPath) [](https://maven-badges.herokuapp.com/maven-central/com.jayway.jsonpath/json-path) [](http://www.javadoc.io/doc/com.jayway.jsonpath/json-path) Jayway JsonPath is a Java port of [Stefan Goessner JsonPath implementation](http://goessner.net/articles/JsonPath/). Getting Started --------------- JsonPath is available at the Central Maven Repository. Maven users add this to your POM. ```xml <dependency> <groupId>com.jayway.jsonpath</groupId> <artifactId>json-path</artifactId> <version>2.9.0</version> </dependency> ``` If you need help ask questions at [Stack Overflow](http://stackoverflow.com/questions/tagged/jsonpath). Tag the question 'jsonpath' and 'java'. JsonPath expressions always refer to a JSON structure in the same way as XPath expression are used in combination with an XML document. The "root member object" in JsonPath is always referred to as `$` regardless if it is an object or array. JsonPath expressions can use the dot–notation `$.store.book[0].title` or the bracket–notation `$['store']['book'][0]['title']` Operators --------- | Operator | Description | | :------------------------ | :----------------------------------------------------------------- | | `$` | The root element to query. This starts all path expressions. | | `@` | The current node being processed by a filter predicate. | | `*` | Wildcard. Available anywhere a name or numeric are required. | | `..` | Deep scan. Available anywhere a name is required. | | `.<name>` | Dot-notated child | | `['<name>' (, '<name>')]` | Bracket-notated child or children | | `[<number> (, <number>)]` | Array index or indexes | | `[start:end]` | Array slice operator | | `[?(<expression>)]` | Filter expression. Expression must evaluate to a boolean value. | Functions --------- Functions can be invoked at the tail end of a path - the input to a function is the output of the path expression. The function output is dictated by the function itself. | Function | Description | Output type | |:------------|:-------------------------------------------------------------------------------------|:---------------------| | `min()` | Provides the min value of an array of numbers | Double | | `max()` | Provides the max value of an array of numbers | Double | | `avg()` | Provides the average value of an array of numbers | Double | | `stddev()` | Provides the standard deviation value of an array of numbers | Double | | `length()` | Provides the length of an array | Integer | | `sum()` | Provides the sum value of an array of numbers | Double | | `keys()` | Provides the property keys (An alternative for terminal tilde `~`) | `Set<E>` | | `concat(X)` | Provides a concatinated version of the path output with a new item | like input | | `append(X)` | add an item to the json path output array | like input | | `first()` | Provides the first item of an array | Depends on the array | | `last()` | Provides the last item of an array | Depends on the array | | `index(X)` | Provides the item of an array of index: X, if the X is negative, take from backwards | Depends on the array | Filter Operators ----------------- 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")]`). | Operator | Description | | :----------------------- | :-------------------------------------------------------------------- | | `==` | left is equal to right (note that 1 is not equal to '1') | | `!=` | left is not equal to right | | `<` | left is less than right | | `<=` | left is less or equal to right | | `>` | left is greater than right | | `>=` | left is greater than or equal to right | | `=~` | left matches regular expression [?(@.name =~ /foo.*?/i)] | | `in` | left exists in right [?(@.size in ['S', 'M'])] | | `nin` | left does not exists in right | | `subsetof` | left is a subset of right [?(@.sizes subsetof ['S', 'M', 'L'])] | | `anyof` | left has an intersection with right [?(@.sizes anyof ['M', 'L'])] | | `noneof` | left has no intersection with right [?(@.sizes noneof ['M', 'L'])] | | `size` | size of left (array or string) should match right | | `empty` | left (array or string) should be empty | Path Examples ------------- Given the json ```javascript { "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 }, { "category": "fiction", "author": "Herman Melville", "title": "Moby Dick", "isbn": "0-553-21311-3", "price": 8.99 }, { "category": "fiction", "author": "J. R. R. Tolkien", "title": "The Lord of the Rings", "isbn": "0-395-19395-8", "price": 22.99 } ], "bicycle": { "color": "red", "price": 19.95 } }, "expensive": 10 } ``` | JsonPath | Result | |:-------------------------------------------------------------------| :----- | | `$.store.book[*].author` | The authors of all books | | `$..author` | All authors | | `$.store.*` | All things, both books and bicycles | | `$.store..price` | The price of everything