spring中的ImportSelector接口示例详解

public class DataSourceSelector implements ImportSelector {
    @Override
    public String[] selectImports(AnnotationMetadata importingClassMetadata) {
        // 根据条件动态选择要导入的配置类
        if (isEnterpriseCustomer()) {
            return new String[]{"com.example.EnterpriseDataSourceConfig"};
        } else {
            return new String[]{"com.example.StandardDataSourceConfig"};
        }
    }
    private boolean isEnterpriseCustomer() {
        // 实际场景中可能会根据数据库中的配置或者请求头中的信息来判断
        return true;
    }
}

@Configuration
@Import(DataSourceSelector.class)
public class AppConfig {
    // 其他配置
}

import org.springframework.context.annotation.ImportSelector;
import org.springframework.core.type.AnnotationMetadata;
public class CustomImportSelector implements ImportSelector {
    @Override
    public String[] selectImports(AnnotationMetadata importingClassMetadata) {
        // 在这里实现你的逻辑来决定要导入哪些配置类
        return new String[]{
            "com.example.config.FeatureAConfig",
            "com.example.config.FeatureBConfig"
        };
    }
}

import org.springframework.context.annotation.ImportSelector;
import org.springframework.core.type.AnnotationMetadata;
import org.springframework.core.env.Environment;
import org.springframework.beans.factory.annotation.Autowired;
public class CustomImportSelector implements ImportSelector {
    @Autowired
    private Environment environment;
    @Override
    public String[] selectImports(AnnotationMetadata importingClassMetadata) {
        String activeProfile = environment.getProperty("spring.profiles.active");
        if ("dev".equals(activeProfile)) {
            return new String[]{
                "com.example.config.DevFeatureConfig"
            };
        } else if ("prod".equals(activeProfile)) {
            return new String[]{
                "com.example.config.ProdFeatureConfig"
            };
        }
        return new String[]{
            "com.example.config.DefaultFeatureConfig"
        };
    }
}

import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
@Configuration
@Import(CustomImportSelector.class)
public class AppConfig {
    // 其他配置
}