How to add custom field in model with Spring boot projection?

Now I have two classes

class A{      @Column(name="num1")      private BigDecimal num1;            private B b;            //getter and setter  }  

And

class B{      @Column(name="num2")      private BigDecimal num2;            //getter and setter  }  

I have tried to add a new field called total in class A and add the getter in AView.

class A{      @Column(name="num1")      private BigDecimal num1;            // a custom field that does not exist in db      private BigDecimal total;            //suppose we have joined two entity using @join annotation      private B b;            public getTotal(){        return this.num1.add(b.num2);       }            // other getter and setter    }      public interface AView{        // add num1 and num2      BigDecimal total();  }  

But it showed error message.

I have found a solution but it does not work. https://www.baeldung.com/spring-data-jpa-projections#2-open-projections Are there any other solutions? Thank you!

https://stackoverflow.com/questions/65608941/how-to-add-custom-field-in-model-with-spring-boot-projection January 07, 2021 at 04:28PM