如何将JSON字符串转换为Java对象?
在以下示例中,我们将使用ObjectMapperJackson库中的类将JSON字符串转换为Java对象。此类提供了一种readValue(String,Class<T>)将JSON字符串反序列化为Java对象的方法。该方法的第一个参数是JSON字符串,第二个参数是转换的结果类型。
package org.nhooo.example.jackson;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.io.IOException;
public class JsonToObject {
public static void main(String[] args) {
String json = "{\"id\": 1, \"name\": \"The Beatles\"}";
ObjectMapper mapper = new ObjectMapper();
try {
Artist artist = mapper.readValue(json, Artist.class);
System.out.println("Artist = " + artist);
System.out.println("artist.getId() = " + artist.getId());
System.out.println("artist.getName() = " + artist.getName());
} catch (IOException e) {
e.printStackTrace();
}
}
}这是Artist类的定义。
package org.nhooo.example.jackson;
public class Artist {
private Long id;
private String name;
public Artist() {
}
public Artist(Long id, String name) {
this.id = id;
this.name = name;
}
// Getters & Setters
@Override
public String toString() {
return "Artist{" +
"id=" + id +
", name='" + name + '\'' +
'}';
}
}上面的代码片段将打印到以下输出:
Artist = Artist{id=1, name='The Beatles'}
artist.getId() = 1
artist.getName() = The BeatlesMaven依赖
<!-- http://repo1.maven.org/maven2/com/fasterxml/jackson/core/jackson-databind/2.8.6/jackson-databind-2.8.6.jar -->
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.8.6</version>
</dependency>