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[ Java Common Class Libraries](#)\\n\\n* * *\\n\\nJackson is a high-performance JSON processing library for Java, which can:\\n\\n* Serialize Java objects to JSON format (Object → JSON)\\n* Deserialize JSON to Java objects (JSON → Object)\\n\\nJackson is one of the most popular JSON processing libraries in the Java ecosystem due to its speed, powerful features, and ease of use.\\n\\n### Jackson Core Modules\\n\\n* 1. Jackson Core: The core module of Jackson, providing basic JSON parsing and generation functionality.\\n* 2. Jackson Annotations: Contains various annotations for controlling serialization and deserialization process.\\n* 3. Jackson Databind: Provides data binding functionality, enabling conversion between Java objects and JSON.\\n\\n* * *\\n\\n## Basic Usage\\n\\n### Add Dependency\\n\\nFirst, you need to add Jackson dependency to your project (using Maven as an example):\\n\\ncom.fasterxml.jackson.core\\n\\njackson-databind\\n\\n2.13.0\\n\\nA simple example, converting between Java and JSON objects:\\n\\n## Example\\n\\nimport com.fasterxml.jackson.databind.ObjectMapper;\\n\\npublic class JacksonDemo {\\n\\npublic static void main(String[] args)throws Exception{\\n\\n ObjectMapper mapper =new ObjectMapper();\\n\\n// JavaConvert Object to JSON\\n\\n Person person =new Person("Zhang San", 30);\\n\\nString json = mapper.writeValueAsString(person);\\n\\nSystem.out.println(json);\\n\\n// JSONConvert to Java object\\n\\n Person parsedPerson = mapper.readValue(json, Person.class);\\n\\nSystem.out.println(parsedPerson);\\n\\n}\\n\\n}\\n\\nclass Person {\\n\\nprivate String name;\\n\\nprivate int age;\\n\\n// Must have a no-argument constructor\\n\\npublic Person(){}\\n\\npublic Person(String name, int age){\\n\\nthis.name= name;\\n\\nthis.age= age;\\n\\n}\\n\\n// Must have getters and setters\\n\\n// Omit getter/setter and toString methods\\n\\n}\\n\\n### Create ObjectMapper\\n\\n`ObjectMapper` is the core class of Jackson, responsible for serialization and deserialization:\\n\\nObjectMapper mapper = new ObjectMapper();\\n\\n* * *\\n\\n## JSON Serialization (Object → JSON)\\n\\n### Simple Example\\n\\n## Example\\n\\npublic class Person {\\n\\nprivate String name;\\n\\nprivate int age;\\n\\n// Omit constructor, getters and setters\\n\\n}\\n\\nPerson person =new Person("Zhang San", 25);\\n\\nString json = mapper.writeValueAsString(person);\\n\\nSystem.out.println(json);\\n\\n// Output: {"name":"Zhang San","age":25}\\n\\n### Formatted Output\\n\\n## Example\\n\\nString prettyJson = mapper.writerWithDefaultPrettyPrinter()\\n\\n.writeValueAsString(person);\\n\\nSystem.out.println(prettyJson);\\n\\n/*\\n\\n Output:\\n\\n {\\n\\n "name" : "Zhang San",\\n\\n "age" : 25\\n\\n }\\n\\n */\\n\\n* * *\\n\\n## JSON Deserialization (JSON → Object)\\n\\n### Simple Example\\n\\n## Example\\n\\nString json ="{"name":"Li Si","age":30}";\\n\\n Person person = mapper.readValue(json, Person.class);\\n\\nSystem.out.println(person.getName());// Output: Li Si\\n\\n### Read from File\\n\\nPerson person = mapper.readValue(new File("person.json"), Person.class);\\n\\n* * *\\n\\n## Common Annotations\\n\\nJackson provides various annotations to control serialization and deserialization:\\n\\n### @JsonProperty\\n\\nSpecify JSON property name:\\n\\n@JsonProperty("user_name")private String name;\\n### @JsonIgnore\\n\\nIgnore a field:\\n\\n@JsonIgnoreprivate String password;\\n### @JsonFormat\\n\\nFormat date:\\n\\n@JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd")private Date birthDate;\\n\\n* * *\\n\\n## Handling Complex Types\\n\\n### Collection Types\\n\\n## Example\\n\\nList people =Arrays.asList(\\n\\nnew Person("Wang Wu", 28),\\n\\nnew Person("Zhao Liu", 32)\\n\\n);\\n\\nString json = mapper.writeValueAsString(people);\\n\\n// Output: [{"name":"Wang Wu","age":28},{"name":"Zhao Liu","age":32}]\\n\\n### Map Types\\n\\n## Example\\n\\nMap data =new HashMap();\\n\\n data.put("name", "Zhang San");\\n\\n data.put("age", 25);\\n\\n data.put("isStudent", true);\\n\\nString json = mapper.writeValueAsString(data);\\n\\n// Output: {"name":"Zhang San","age":25,"isStudent":true}\\n\\n* * *\\n\\n## Advanced Features\\n\\n### Custom Serialization/Deserialization\\n\\nYou can implement custom serialization and deserialization logic by extending `JsonSerializer` and `JsonDeserializer`.\\n\\n### Polymorphic Type Handling\\n\\nUse `@JsonTypeInfo` and `@JsonSubTypes` annotations to handle inheritance and polymorphism.\\n\\n### Tree Model\\n\\nJackson provides a tree model API for directly manipulating JSON nodes:\\n\\n## Example\\n\\nJsonNode rootNode = mapper.readTree(json);\\n\\nString name = rootNode.get("name").asText();\\n\\nint age = rootNode.get("age").asInt();\\n\\n* * *\\n\\n## Best Practices\\n\\n1. **Reuse ObjectMapper**: Creating `ObjectMapper` instances is expensive, reuse the same instance\\n2. **Handle Exceptions**: Always handle `JsonProcessingException` and `IOException`\\n3. **Use DTO Pattern**: Don't serialize domain models directly, use dedicated Data Transfer Objects (DTO)\\n4. **Consider Performance**: For high-performance scenarios, use `JsonFactory` for low-level operations\\n\\n* * *\\n\\n## Summary\\n\\nJackson is a powerful tool for JSON processing in Java, providing:\\n\\n* Simple and easy-to-use API\\n* High-performance JSON processing capabilities\\n* Rich customization options\\n* Good community support\\n\\nMastering Jackson can greatly improve the efficiency and flexibility of handling JSON data in Java development.\\n\\n[ Java Common Class Libraries](#)