Can you use Autowired with static fields

Question

Is there some way to use  Autowired with static fields  If not  are there some other ways to do this

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Init your autowired component in  PostConstruct method   Component public class TestClass      private static AutowiredTypeComponent component       Autowired    private AutowiredTypeComponent autowiredComponent       PostConstruct    private void init           component   this autowiredComponent           public static void testMethod           component callTestMethod

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Autowired can be used with setters so you could have a setter modifying an static field   Just one final suggestion    DON T

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Component  NewClass   public class NewClass      private static SomeThing someThing        Autowired     public void setSomeThing SomeThing someThing           NewClass someThing   someThing

User · Answer

You can use ApplicationContextAware    Component public class AppContext implements ApplicationContextAware      public static ApplicationContext applicationContext       public AppBeans                Override     public void setApplicationContext ApplicationContext applicationContext  throws BeansException           this applicationContext   applicationContext            then  static ABean bean   AppContext applicationContext getBean  aBean  ABean class

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You can achieve this using XML notation and the MethodInvokingFactoryBean  For an example look here   private static StaticBean staticBean   public void setStaticBean StaticBean staticBean       StaticBean staticBean   staticBean      You should aim to use spring injection where possible as this is the recommended approach but this is not always possible as I m sure you can imagine as not everything can be pulled from the spring container or you maybe dealing with legacy systems   Note testing can also be more difficult with this approach

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Create a bean which you can autowire which will initialize the static variable as a side effect

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private static UserService userService   ApplicationContextHolder getContext   getBean UserService class

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Disclaimer This is by no means standard and there could very well be a better spring way of doing this  None of the above answers address the issues of wiring a public static field   I wanted to accomplish three things    Use spring to  Autowire   Im using  Value  Expose a public static value Prevent modification   My object looks like this  private static String BRANCH    testBranch     Value    content client branch    public void finalSetBranch String branch        BRANCH   branch     public static String BRANCH         return BRANCH      We have checked off 1  amp  2 already now how do we prevent calls to the setter  since we cannot hide it    Component  Aspect public class FinalAutowiredHelper     Before  finalMethods     public void beforeFinal JoinPoint joinPoint        throw new FinalAutowiredHelper   new ModifySudoFinalError          Pointcut  execution   com free content client    finalSetBranch        public void finalMethods        public class ModifySudoFinalError extends Error       private String msg       public ModifySudoFinalError String msg            this msg   msg              Override     public String getMessage             return  Attempted modification of a final property      msg            This aspect will wrap all methods beginning with final and throw an error if they are called   I dont think this is particularly useful  but if you are ocd and like to keep you peas and carrots separated this is one way to do it safely   Important Spring does not call your aspects when it calls a function  Made this easier  to bad I worked out the logic before figuring that out

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Generally  setting static field by object instance is a bad practice  to avoid optional issues you can add synchronized definition  and set it only if     private static Logger logger   Autowired public synchronized void setLogger Logger logger        if  MyClass logger    null                MyClass logger   logger

User · Answer

Wanted to add to answers that auto wiring static field  or constant  will be ignored  but also won t create any error    Autowired private static String staticField    staticValue

User · Answer

In short  no  You cannot autowire or manually wire static fields in Spring  You ll have to write your own logic to do this

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