Interpret the technical principles of the "JSON Unit" framework in the Java class library

The JSON Unit framework is a Java class library for testing and verification of JSON data.It provides a set of convenient features that allow developers to easily assert and compare JSON, and create and analyze JSON objects. The technical principles of the JSON Unit framework are mainly based on two key concepts: assertion and comparison. 1. Adventure: assertion is a method of verifying JSON data to determine the difference between the expected results and the actual results.The JSON Unit framework provides a set of assertions to verify whether the structure and content of the JSON object meets expectations.For example, you can use the `Assertjsonequals` method to compare whether the two JSON objects are exactly equal, or whether the specific part of the JSON object is equal to the specific part of the JSON object with the method of using the` AssertjsonPartEQUALS` method. Below is an example code that uses the JSON Unit framework for assertions: import static com.jayway.jsonassert.JsonAssert.*; String expectedJson = "{\"name\":\"John\",\"age\":30}"; String actualJson = "{\"name\":\"John\",\"age\":30}"; assertJsonEquals(expectedJson, actualJson); 2. Comparison: Comparison is a way to compare the difference between two JSON objects.The JSON Unit framework provides a set of comparison methods to compare the structure and content of the JSON object.For example, you can use the `when` method to specify the JSON object to be compared, and then use the` ISEQUALTO` method to specify the expected JSON object, and finally use the `the then` method to obtain the difference between the two objects. Below is a sample code that uses the JSON Unit framework to compare: import static org.assertj.core.api.Assertions.assertThat; import static com.jayway.jsonassert.JsonAssert.*; String expectedJson = "{\"name\":\"John\",\"age\":30}"; String actualJson = "{\"name\":\"John\",\"age\":40}"; JsonDiffResult result = when(actualJson).isEqualTo(expectedJson).then(); assertThat(result).hasOnlyFields("age"); assertThat(result).hasOnlyValues("40"); In addition to asserting and comparison, the JSON Unit framework also provides other useful functions, such as: -Coloning and analyzing JSON objects: You can use the JSONBUILDER `category of the JSON Unit framework to create and assemble the JSON object, or use the` JSONPARSER` class to analyze and extract the data in the JSON object. Below is an example code that uses the JSON Unit framework to create and analyze the JSON object: import net.javacrumbs.jsonunit.JsonBuilder; import net.javacrumbs.jsonunit.core.Option; import static net.javacrumbs.jsonunit.JsonAssert.*; // Create a json object JsonBuilder builder = new JsonBuilder(); String json = builder.object() .property("name", "John") .property("age", 30) .endObject() .json(); // Analysis of json object JsonParser parser = new JsonParser(); ObjectNode node = parser.parse(json); assertJsonNodePresent(node, "name"); assertJsonNodeValue(node, "age", 30); In summary, the technical principle of the JSON Unit framework is based on the concept of assertion and comparison. By providing a set of convenient methods, developers can easily test and verify JSON data.It also provides the function of creating and analyzing JSON objects to facilitate operation and processing JSON data.