java如何解析json数据

Java可以使用Json库来解析JSON数据。以下是使用Jackson库来解析JSON数据的示例代码：

导入Jackson库的依赖：

<dependency><groupId>com.fasterxml.jackson.core</groupId><artifactId>jackson-databind</artifactId><version>2.12.4</version></dependency>

使用ObjectMapper类将JSON数据转换为Java对象：

import com.fasterxml.jackson.databind.ObjectMapper;public class JsonParser {public static void main(String[] args) {String jsonData = "{\"name\":\"John\", \"age\":30, \"city\":\"New York\"}";try {ObjectMapper objectMapper = new ObjectMapper();Person person = objectMapper.readValue(jsonData, Person.class);System.out.println("Name: " + person.getName());System.out.println("Age: " + person.getAge());System.out.println("City: " + person.getCity());} catch (Exception e) {e.printStackTrace();}}}class Person {private String name;private int age;private String city;// 必须有无参数的构造方法public Person() {}// getters and setterspublic String getName() {return name;}public void setName(String name) {this.name = name;}public int getAge() {return age;}public void setAge(int age) {this.age = age;}public String getCity() {return city;}public void setCity(String city) {this.city = city;}}

以上代码将输出：

Name: JohnAge: 30City: New York

这里使用了ObjectMapper类的readValue()方法来将JSON数据转换为Person对象。Person类是一个简单的POJO类，具有与JSON数据对应的属性和相应的getter和setter方法。