Lombok @builder在扩展另一个类的类上 [英] Lombok @builder on a class that extends another class

问题描述

我有两个类 Child extends 父。我需要在这些类上添加@Builder注释，这样我就不需要为我自己创建构建器。

  package jerry; //内部编译器错误：java.lang.NullPointerException 
 
 import lombok.AllArgsConstructor; 
 import lombok.Builder; 
 
 @AllArgsConstructor（onConstructor = @ __（@ Builder））
 public class Child extends Parent {
 //此行的多个标记
 //  - 隐式超级构造函数Parent（）未定义。必须显式调用另一个构造函数
 //  - 覆盖java.lang.Object.toString 
 
 private String a; 
 private int b; 
 private boolean c; 
 
} 
 
 
 @Builder 
 public class Parent {
 private double d; 
私人浮动e; 
} 
  

我需要能够构建子实例

pre $ Child child = Child.builder（）。a（aVal）。b（1000）.c（true）.d（10.1）。 E（20.0F）.build（）;


但是到目前为止，我收到了代码注释中提到的错误。任何人都可以指出我如何通过lombok或任何其他类似的图书馆来实现它吗？

子问题

为什么 @AllArgsConstructor（onConstructor = @ __（@ Autowired））编译但是 @AllArgsConstructor（onConstructor = @ __（@ Builder））不是？ https://blog.codecentric.de/en/2016/05/reducing -boilerplate-code-project-lombok / （ @Builder和inheritance 部分）

调整到您的课程

  @AllArgsConstructor 
 public class Parent {
 private double d; 
私人浮动e; 
} 
 
 public class Child extends Parent {
 private String a; 
 private int b; 
 private boolean c; 
 
 @Builder 
 public Child（String a，int b，boolean c，double d，float e）{
 super（d，e）; 
 this.a = a; 
 this.b = b; 
 this.c = c; 
 
 
 $ / code $ / pre 
 $ b $ p 
使用此设置
 
 
  Child child = Child.builder（）。a（aVal）。b（1000）.c（true）.d（10.1）.e（20.0 F）.build（）; 
  
正常工作
 
I have two classes Child extends Parent. I need to put @Builder annotation on the classes such that I do not need to create the builder my self.
package jerry;// Internal compiler error: java.lang.NullPointerException

import lombok.AllArgsConstructor;
import lombok.Builder;

@AllArgsConstructor(onConstructor=@__(@Builder))
public class Child extends Parent { 
//Multiple markers at this line
//  - Implicit super constructor Parent() is undefined. Must explicitly invoke another constructor
//  - overrides java.lang.Object.toString

   private String a;
   private int b;
   private boolean c;

}


@Builder
public class Parent {
    private double d;
    private float e;
}
I need to be able to build child instance such that 
Child child = Child.builder().a("aVal").b(1000).c(true).d(10.1).e(20.0F).build();
But so far I am getting the errors mentioned in side that code comments. Can any one point me to the right direction how to achieve it with lombok or any other similar library ?

Sub-question

Why does @AllArgsConstructor(onConstructor=@__(@Autowired)) compile but @AllArgsConstructor(onConstructor=@__(@Builder)) does not?
解决方案
See in https://blog.codecentric.de/en/2016/05/reducing-boilerplate-code-project-lombok/ (@Builder and inheritance part)

Adjusted to your classes
@AllArgsConstructor
public class Parent {
  private double d;
  private float e;
}

public class Child extends Parent {
  private String a;
  private int b;
  private boolean c;

  @Builder
  public Child(String a, int b, boolean c, double d, float e) {
    super(d, e);
    this.a = a;
    this.b = b;
    this.c = c;
  }
}
With this setup
Child child = Child.builder().a("aVal").b(1000).c(true).d(10.1).e(20.0F).build();
works correctly

                        
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