排除 pojo 响应中的空字段

Question

我想从 pojo 中排除空字段

****交易历史BO Pojo**

package main.java.com.as.model;

import com.fasterxml.jackson.annotation.JsonInclude;

@JsonInclude(JsonInclude.Include.NON_NULL)
public class TransactionHistoryBO 
{
  private String processId;
  private String dateTime;
  private Integer status;
  private Double pointsEarned;
  private String productName;
  private String receiptNumber;
   
 public String getProcessId() {
  return processId;
 }
 public void setProcessId(String processId) {
  this.processId = processId;
 }


 public String getDateTime() {
  return dateTime;
 }
 public void setDateTime(String dateTime) {
  this.dateTime = dateTime;
 }
 public Integer getStatus() {
  return status;
 }
 public void setStatus(Integer status) {
  this.status = status;
 }
 
 public Double getPointsEarned() {
  return pointsEarned;
 }

 public void setPointsEarned(Double pointsEarned) {
  this.pointsEarned = pointsEarned;
 }

 public String getProductName() {
  return productName;
 }
 
 public void setProductName(String productName) {
  this.productName = productName;
 }
 
 public String getReceiptNumber() {
  return receiptNumber;
 }
 public void setReceiptNumber(String receiptNumber) {
  this.receiptNumber = receiptNumber;
 }



}

**

交易历史响应 pojo

public class TransactionHistoryResponse 
{
 private ArrayList<TransactionHistoryBO> transactions;
 
 @JsonInclude(JsonInclude.Include.NON_NULL)
 public ArrayList<TransactionHistoryBO> getTransactions() {
  return transactions;
 }
 @JsonInclude(Include.NON_NULL)
 public void setTransactions(ArrayList<TransactionHistoryBO> transactions) {
  this.transactions = transactions;
 }

 
 }

事务历史记录 BO 类型的数组列表用于事务历史响应 pojo.This 是我在 response.I 中显示的确切 pojo 想排除 字段为 null交易历史 BO 中的值。 我尝试使用@JsonInclude(JsonInclude.Include.NON_NULL)。它不工作.. 也尝试使用 JsonSerialize，但它是 deprecated.Jackson 使用的版本是 2.2.2.

任何帮助将不胜感激..请帮助..

Answer 1

@JsonInclude(JsonInclude.Include.NON_NULL)
public class TransactionHistoryBO { ... }

@JsonInclude(JsonInclude.Include.NON_NULL)
public class TransactionHistoryResponse { ... }

public class App {

    public static void main(String... args) throws JsonProcessingException {

        ObjectMapper om = new ObjectMapper();

        TransactionHistoryResponse thr = new TransactionHistoryResponse();
        TransactionHistoryBO thbo = new TransactionHistoryBO();
        thbo.setProductName("TEST");
        thr.setTransactions(new ArrayList<TransactionHistoryBO>());
        thr.getTransactions().add(thbo);
        System.out.print(om.writerWithDefaultPrettyPrinter().writeValueAsString(thr));
    }

}

产生输出：

{
  "transactions" : [ {
    "productName" : "TEST"
  } ]
}

没有使用其他注释。只需将 @JsonInclude 注释添加到类而不是属性。

更新：

将自定义 JacksonJsonProvider 添加到您的应用程序

@Provider
public class CustomJsonProvider extends ResteasyJackson2Provider {

    @Override
    public void writeTo(Object value, Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType, MultivaluedMap<String, Object> httpHeaders, OutputStream entityStream) throws IOException {

        ObjectMapper mapper = locateMapper(type, mediaType);
        mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);

        super.writeTo(value, type, genericType, annotations, mediaType, httpHeaders, entityStream);
    }

}

在您的 web.xml

中注册此提供商

<context-param> 
    <param-name>resteasy.providers</param-name> 
    <param-value>com.package.CustomJsonProvider</param-value> 
</context-param>

在有和没有这个的情况下都进行了测试，它都有效。

排除 pojo 响应中的空字段

Excluding null fields in pojo response

java

json

pojo

jackson