很少有Jackson示例将JSON数组字符串转换为List

// JSON array string// [{"name":"mkyong", "age":37}, {"name":"fong", "age":38}]ObjectMapper mapper = new ObjectMapper();String json = "[{\"name\":\"mkyong\", \"age\":37}, {\"name\":\"fong\", \"age\":38}]";// 1. convert JSON array to Array objectsPerson[] pp1 = mapper.readValue(json, Person[].class);// 2. convert JSON array to List of objectsList<Person> ppl2 = Arrays.asList(mapper.readValue(json, Person[].class));

<dependency><groupId>com.fasterxml.jackson.core</groupId><artifactId>jackson-databind</artifactId><version>2.9.8</version></dependency>

PS已在Jackson 2.9.8中测试

1.将JSON数组字符串转换为List

1.1 JSON数组字符串

[{"name":"mkyong", "age":37}, {"name":"fong", "age":38}]

1.2创建一个对象以映射上述JSON字段。

package com.mkyong;public class Person {String name;Integer age;//getters and setters
}

1.3将JSON数组字符串转换为List

package com.mkyong;import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.ObjectMapper;import java.io.IOException;
import java.util.Arrays;
import java.util.List;public class JacksonArrayExample {public static void main(String[] args) {ObjectMapper mapper = new ObjectMapper();String json = "[{\"name\":\"mkyong\", \"age\":37}, {\"name\":\"fong\", \"age\":38}]";try {// 1. convert JSON array to Array objectsPerson[] pp1 = mapper.readValue(json, Person[].class);System.out.println("JSON array to Array objects...");for (Person person : pp1) {System.out.println(person);}// 2. convert JSON array to List of objectsList<Person> ppl2 = Arrays.asList(mapper.readValue(json, Person[].class));System.out.println("\nJSON array to List of objects");ppl2.stream().forEach(x -> System.out.println(x));// 3. alternativeList<Person> pp3 = mapper.readValue(json, new TypeReference<List<Person>>() {});System.out.println("\nAlternative...");pp3.stream().forEach(x -> System.out.println(x));} catch (IOException e) {e.printStackTrace();}}
}

输出量

1. JSON array to Array objects...
Person{name='mkyong', age=37}
Person{name='fong', age=38}2. JSON array to List of objects
Person{name='mkyong', age=37}
Person{name='fong', age=38}3. Alternative...
Person{name='mkyong', age=37}
Person{name='fong', age=38}

参考文献

• Jackson-将JSON字符串转换为Map
• 杰克逊数据绑定
• 杰克逊2 –将Java对象与JSON相互转换

翻译自: https://mkyong.com/java/jackson-convert-json-array-string-to-list/