java - 将默认公共(public)构造函数添加到生成的构建器内部类

Question

我正在使用 Lombok 框架来生成样板代码，例如:

import lombok.*;


@Builder
@Value
public final class SocketConfig {

    @Builder.Default
    private int soTimeoutMilliseconds = 0;

    @Builder.Default
    private boolean soReuseAddress = false;

    @Builder.Default
    private int soLingerSeconds = -1;

    private boolean soKeepAlive;

    @Builder.Default
    private boolean tcpNoDelay = false;

} 

为了创建构建器实例，我曾经调用SocketConfig.builder()。但为了更好地与 spring bean 创建集成，我尝试创建一个 FactoryBean。但由于构建器类上缺少默认构造函数而出现编译错误，没有找到任何有关它的文档。 Lombok 可以吗？我的意思是在构建器上而不是在原始类上创建默认构造函数。换句话说，我需要两个选项来创建构建器实例:SocketConfig.builder() 或通过 new SocketConfig.SocketConfigBuilder()。

import org.springframework.beans.factory.FactoryBean;

public class SocketConfigFactoryBean extends SocketConfig.SocketConfigBuilder implements FactoryBean<SocketConfig> {



    @Override
    public SocketConfig getObject() throws Exception {
        return build();
    }

    @Override
    public Class<?> getObjectType() {
        return SocketConfig.class;
    }

    @Override
    public boolean isSingleton() {
        return false;
    }
}

Answer 1

使用注释NoArgsConstructor :

Generates a no-args constructor. Will generate an error message if such a constructor cannot be written due to the existence of final fields.

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