某些业务场景需要我们将方法定义成静态方法，该静态方法还依赖别的被容器管理的类
@Service
public class Foo {
public int doStuff() {
System.out.println("hehe");
return 1;
}
}
@Component
public class Boo {
@Autowired
private static Foo foo;
public static void test() {
foo.doStuff();
}
}
这样必然报java.lang.NullPointerException: null异常，解决办法：
1.将@Autowire加到构造方法上
@Component
public class Boo {
private static Foo foo;
@Autowired
public Boo(Foo foo) {
Boo.foo = foo;
}
}
2.用@PostConstruct注解
@Component
public class Boo {
private static Foo foo;
@Autowired
private Foo foo2;
@PostConstruct
public void beforeInit() {
foo = foo2;
}
public static void test() {
foo.doStuff();
}
}
