首先感谢Lombok,我们的java代码现在更加简洁和清晰。 我的使用情况是我想创建一个不可变类。为此,我将使用@Value注释。此外,我想使用构建器功能,因此我将使用@Builder注释。我的问题是是否可以在单个类上同时使用@Builder和@Value。这是Lombok用户/开发者推荐的良好实践吗。
当然可以。要检查,只需delombok您的代码并查看它生成了什么。以此示例为例:
@Builder
@Value
public class Pair {
private Object left;
private Object right;
}
进行delombok处理后,这将产生:
public class Pair {
private Object left;
private Object right;
@java.beans.ConstructorProperties({ "left", "right" })
Pair(Object left, Object right) {
this.left = left;
this.right = right;
}
public static PairBuilder builder() {
return new PairBuilder();
}
public Object getLeft() {
return this.left;
}
public Object getRight() {
return this.right;
}
public boolean equals(Object o) {
if (o == this) return true;
if (!(o instanceof Pair)) return false;
final Pair other = (Pair) o;
final Object this$left = this.left;
final Object other$left = other.left;
if (this$left == null ? other$left != null : !this$left.equals(other$left)) return false;
final Object this$right = this.right;
final Object other$right = other.right;
if (this$right == null ? other$right != null : !this$right.equals(other$right)) return false;
return true;
}
public int hashCode() {
final int PRIME = 59;
int result = 1;
final Object $left = this.left;
result = result * PRIME + ($left == null ? 0 : $left.hashCode());
final Object $right = this.right;
result = result * PRIME + ($right == null ? 0 : $right.hashCode());
return result;
}
public String toString() {
return "Pair(left=" + this.left + ", right=" + this.right + ")";
}
public static class PairBuilder {
private Object left;
private Object right;
PairBuilder() {
}
public Pair.PairBuilder left(Object left) {
this.left = left;
return this;
}
public Pair.PairBuilder right(Object right) {
this.right = right;
return this;
}
public Pair build() {
return new Pair(left, right);
}
public String toString() {
return "Pair.PairBuilder(left=" + this.left + ", right=" + this.right + ")";
}
}
}
因此,您可以明确使用@Value
和@Builder
private
访问修饰符来写更少的代码,因为根据 Lombok 的 @Value 注解文档所述 - "... 字段默认情况下是 private
和 final
。" - Peter Sivák从版本1.16.10开始,当您同时使用两者时,构造函数不是公共的。
您可以添加@AllArgsConstructor来弥补此问题。
@Value
和@Builder
,构造函数将变为包私有。 - Rothin Sen
@Value
@Builder
@ApiModel(description = "Model to represent annotation")
public class Annotation {
@NonNull
@ApiModelProperty(value = "Unique identifier")
private String id;
}