java - 如何在 Spring 中使用自定义 BeanName 创建 bean？

Question

问题
有一个Processor处理基于其 typesToProcess 的类:

import org.springframework.stereotype.Component;

@Component
public class Processor {

    private String typesToProcess;

    public Processor(String typesToProcess) {
        this.typesToProcess = typesToProcess;
    }

    public void process(String type) {
        if (typesToProcess.equals(type)) {
            // process
        }
    }
}

我需要创建一些 Processor实例在不同的地方工作。问题是我不知道有多少 Processor应该在 Spring 应用程序引导时创建实例，以及它们的“typesToProcess”。更进一步， Processor的数量应用程序运行时，实例可能会发生变化。我需要定期从存储在数据库中的一些配置文件中读取类型。
尝试
我可以解决这个问题的一种方法是使用 typesToProcess + Processor作为 bean 名，虽然我知道它不会工作。有没有其他办法？

import com.meituan.picture.selection.processor.impl.Processor;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;

public class ProcessorContainer implements ApplicationContextAware {

    private ApplicationContext applicationContext;

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        this.applicationContext = applicationContext;
    }

    public Processor getProcessor(String type) {
        String realBeanName = "processor" + type;
        // obviouslly this wont work
        return applicationContext.getBean(realBeanName, Processor.class);
    }
    
}

Answer 1

我通过将 bean 的范围指定为 prototype 解决了类似的问题不使用bean名称。下面的例子解释了我的实现:
创建您的 Processor类如下图:

import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Component;

import lombok.Getter;
import lombok.Setter;

@Component
@Getter
@Setter
@Scope("prototype")
public class Processor {
    private String typesToProcess;

    public Processor(String typesToProcess) {
        this.typesToProcess = typesToProcess;
    }

    public void process(String type) {
        if (typesToProcess.equals(type)) {
            // process
        }
    }
}

实现 ApplicationContextAware在运行时生成 bean:

import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Service;

@Service
public class ApplicationContextAwareImpl implements ApplicationContextAware {

    private static ApplicationContext context;

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) {
        ApplicationContextAwareImpl.initApplicationContext(applicationContext);
    }

    private static void initApplicationContext(ApplicationContext applicationContext) {
        ApplicationContextAwareImpl.context = applicationContext;
    }

    public static <T> T getBean(Class<T> requiredType) {
        return context.getBean(requiredType);
    }

    public static Processor getProcessor(String typesToProcess) {
        Processor processor = ApplicationContextAwareImpl.getBean(Processor.class);
        processor.setTypesToProcess(typesToProcess);

        return processor;
    }
}

使用 ApplicationContextAwareImpl.getProcessor()以编程方式生成bean的方法:

Processor type1Processor = ApplicationContextAwareImpl.getProcessor("type1");