@Order:注解@Order不能决定Spring容器加载Bean的顺序,只能决定执行顺序
1,注解类源码
@Retention(RetentionPolicy.RUNTIME)@Target({ElementType.TYPE, ElementType.METHOD, ElementType.FIELD})@Documentedpublic @interfaceOrder{/**
* The order value.
* <p>Default is {@link Ordered#LOWEST_PRECEDENCE}.
* @see Ordered#getOrder()
*/intvalue()default Ordered.LOWEST_PRECEDENCE;}
2,常量类
publicinterfaceOrdered{/**
* Useful constant for the highest precedence value.
* @see java.lang.Integer#MIN_VALUE
*/int HIGHEST_PRECEDENCE= Integer.MIN_VALUE;/**
* Useful constant for the lowest precedence value.
* @see java.lang.Integer#MAX_VALUE
*/int LOWEST_PRECEDENCE= Integer.MAX_VALUE;intgetOrder();}
注解可以作用在类、方法、字段声明(包括枚举常量);
注解有一个int类型的参数,可以不传,默认是最低优先级;
通过常量类的值我们可以推测参数值越小优先级越高;
3,代码测试
@Configuration(proxyBeanMethods=false)publicclassCatConfig{@Bean@Order(3)public Catcat1(){
System.err.println("order1------>");returnnewCat("cat1()");}@Bean@Order(2)public Catcat2(){
System.err.println("order2------>");returnnewCat("cat2()");}@Bean@Order(1)public Catcat3(){
System.err.println("order3------>");returnnewCat("cat3()");}@Beanpublic CatCat4(List<Cat> cat){
cat.forEach(s->System.out.println(s.getName()));return cat.get(1);}}
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