如何将多个对象从Angular2发送到Java Spring后端

Question

I am trying to send two objects ( CustomerAcct and Product ) from Angular 2 to restful services (Java Spring). I am using a wrapper object called CustProduct , which has two objects in it, CustomerAcct and Product. Somehow on the back end CustomerAcct object is null but Product object is not.

Here is my code:

GUI:

CustProduct class:

export class CustProduct { public ca: CustomerAcct; public prod: Product }

Service:

addProductToCustomer(cp: CustProduct): Observable<Boolean> {

     let body = JSON.stringify(cp);
     let headers = new Headers({'Content-Type': 'application/json'});
     let options = new RequestOptions({ headers: headers });
     let url = 'my-url';

     return this.http.post(my-url, body, options)
                     .map(this.extractData)
                     .catch(this.hadnleError);
}

Backend code:

java classes:
@Entity
@Table(name="CUSTOMER_ACCT")
public class CustomerAcct {
    @Id
@Column(name="CUSTOMER_ACCT_ID")
private long CUSTOMER_ACCT_ID;
@Column (name="CUSTOMER_NAME")
private long CUSTOMER_NAME;

other additional fields
}

@Entity
@Table(name="PRODUCT")
public class Product {
@Id
@Column(name="PRODUCT_ID")
private long PRODUCT_ID;
@Column(name="PROD_DESC")
private String PROD_DESC;

other additional fields
  }

public class CustomerProduct {
CustomerAcct customerAcct;
Product product;
}

public boolean addProductToCustomer(@RequestBody CustomerProduct cp) {
       CustomerAcct ca = cp.customerAcct;
       Product prod = cp.product;

       // Here CustomerAcct is null, but I do see data in Product object
}

I don't understand why it is dropping CustomerAcct object. If I send CustomerAcct object in @RequestBody by itself, it works but not in the wrapper object. My class definitions on GUI and backend are same.

Thanks for you help.

Answer 1

You're using a simple JSON conversion, which means that in the JSON object your keys are ca and prod . By default, Jackson expects the keys to match the field names, which are customerAcct and product . The simplest approach is probably to annotate your Java fields with @JsonField("ca") . (Alternately, you could rename the properties in either Java or JavaScript.)