Jackson 更改字段名称

17 Mar 2025 | 阅读 2 分钟

当我们序列化一个 Java 对象时，我们需要更改特定字段的名称，以便将其映射到另一个 JSON 属性。这是 Jackson 最常用和重要的概念之一，需要学习和理解。

为了更改字段名称，我们使用 @JsonProperty 注解。在注解构造函数中，我们传递属性的名称。

让我们举一个例子来了解如何使用 @JsonProperty 注解来更改字段名称以进行序列化。

ChangeNameOfFieldExample.java

//import required classes and package if any  

import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;

//create class ChangeNameOfFieldExample to understand how we can change the name of the field while serializing
public class ChangeNameOfFieldExample {  

	//main() methods start  
	public static void main(String args[]) {  

		// create an instance of ObjectMapper class  
		ObjectMapper mapper = new ObjectMapper();  

		String json = "{\"name\":\"ABES\",\"university\":\"AKTU\", \"address\":\"NH-24 Highway GZB UP\", \"rank\":\"1\"}";  
	       
		// de-serializing Json into Java object  
		College colg;
		try {
			colg = mapper.readerFor(College.class).readValue(json);
			
			// print id, name and course of student  
		    System.out.println(colg.getCollegeName());  
		    System.out.println(colg.getUniversityName());  
		    System.out.println(colg.getAddress());
		    System.out.println(colg.getRank());
		    
		} catch (JsonMappingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (JsonProcessingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}  
} 
//create class College
class College {    

	//Creating properties of College class    
	private String name;      
	private String university;   
	private String address; 
	private String rank;   
	
	// default constructor 
	College(){
		
	}
	
	// constructor  
	College(String name, String university, String address, String rank){  
		this.name = name;  
		this.university = university;  
		this.address = address;  
		this.rank = rank;  
	}  
	@JsonProperty("name")  
	public String getCollegeName() {  
		return name;  
	}
	public void setCollegeName(String name) {  
		this.name = name;  
	}
	@JsonProperty("university")  
	public String getUniversityName() {  
		return university;  
	}
	public void setUniversityName(String university) {  
		this.university = university;
	}
	public String getAddress() {  
		return address;  
	}
	public void setAddress(String address) {  
		this.address = address;  
	}
	public String getRank() {  
		return rank;  
	}
	public void setRank(String rank) {  
		this.rank = rank;  
	}
}

输出