Spring Framework

The interface Ordered can be implemented by any object which can be ordered in some way e.g. if they are elements of a collection, they can be arranged by a provided index. Only one method is to be implemented: int getOrder() which should return the desired index of this object in the collection.

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.*;
import org.springframework.core.Ordered;
import org.springframework.stereotype.Component;

import java.util.List;

@PropertySource("classpath:app-props.properties")
@Configuration
@ComponentScan(basePackageClasses = ListInjectionScanRefOrderedExample.class,
                    useDefaultFilters = false,
                    includeFilters = @ComponentScan.Filter(
                                        type = FilterType.ASSIGNABLE_TYPE,
                                        value = {ListInjectionScanRefOrderedExample.class}))

public class ListInjectionScanRefOrderedExample {

    public static void main (String[] args) {
        AnnotationConfigApplicationContext context =
                            new AnnotationConfigApplicationContext(
                                                ListInjectionScanRefOrderedExample.class);

        TestBean bean = context.getBean(TestBean.class);
        System.out.println(bean.getRefBeanServices());
    }

    @Component
    public static class TestBean {

        private List<RefBeanService> refBeanServices;

        @Autowired
        public void setRefBeanServices (List<RefBeanService> refBeanServices) {
            this.refBeanServices = refBeanServices;
        }

        public List<RefBeanService> getRefBeanServices () {
            return refBeanServices;
        }
    }

    public static interface RefBeanService extends Ordered {
        String getStr ();
    }

    @Component
    public static class RefBean implements RefBeanService {
        private String str;

        public String getStr () {
            return str;
        }

        @Value("${some-prop1:defaultStr}")
        public void setStr (String str) {
            this.str = str;
        }

        @Override
        public String toString () {
            return "RefBean{str='" + str + "'}";
        }

        @Override
        public int getOrder () {
            return 3;
        }
    }

    @Component
    public static class RefBean2 implements RefBeanService {
        private String str;

        @Override
        public String getStr () {
            return str;
        }

        @Value("${some-prop2:defaultStr}")
        public void setStr (String str) {
            this.str = str;
        }

        @Override
        public String toString () {
            return "RefBean{str='" + str + "'}";
        }

        @Override
        public int getOrder () {
            return 1;
        }
    }

    @Component
    public static class RefBean3 implements RefBeanService {
        private String str;

        @Override
        public String getStr () {
            return str;
        }

        @Value("${some-prop3:defaultStr}")
        public void setStr (String str) {
            this.str = str;
        }

        @Override
        public String toString () {
            return "RefBean{ str='" + str + "'}";
        }

        @Override
        public int getOrder () {
            return 2;
        }
    }
}

Spring Framework - Ordered Examples

See Also