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Initiate object via constructor through #AutoWired during runtime

I was new to Springboot application using the #Autowired to perform the dependency injection. We can use #Autowired directly by initiate that class object for class that has none or default parameterless constructor. But what if a class has some parameter in its constructor, and I would like to initiate it during runtime conditionally and automatically, is it possible to do that?
For example
#Component
public class SomeContext {
private String name;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
#Component
public class SomeBuilder {
private final SomeContext ctx;
#Autowired
public SomeBuilder(SomeContext ctx) {
this.ctx = ctx;
}
public void test() {
System.out.println("ctx name: " + ctx.getName());
}
}
#Service
public class SomeService {
#Autowired
SomeBuilder someBuilder;
public void run(SomeContext ctx) {
if (ctx != null) {
// I want someBuilder to be initiated here in someway with my input ctx
// but NOT doing through new with constructor like below
// someBuilder = new SomeBuilder(ctx);
someBuilder.test(); // ctx name: null, I would expect to see "ctx name: someUser", while ctx was injected into someBuilder in any possible way
}
}
}
#RestController
public class HelloWorldController
{
#Autowired
SomeService someService;
#RequestMapping("/")
public String hello() {
SomeContext someContext = new SomeContext();
someContext.setName("someUser");
someService.run(someContext);
return "Hello springboot";
}
}

I'm not sure I've got your question right, but from the code it looks like you really want to create a new instance of SomeBuilder every time you call the run method of SomeService.
If so, I think the first thing to understand is that in general the injection magic happens only if the class is managed by Spring by itself. Read, if spring creates the object of the class - it will inject stuff into it otherwise you're on your own here.
The next thing to understand is that, if you have a object of class SomeBuilder managed by spring and you want to inject SomeContext into it, this SomeContext instance has to be managed by spring as well.
Bottom line, spring can deal only with objects that it manages. These objects are stored in a 'global registry' of all the objects called ApplicationContext in spring.
Now Spring has a concept of prototype scope vs. singleton scope. By Default all the beans are singletons, however you can easily alter this behavior. This has two interesting consequences:
You Can create prototype objects being injected into the singleton upon each invocatino (of method run in your case, so the SomeBuilder can and I believe should be a prototype)
Prototype objects are not stored in the application contexts so the capabilities of injecting stuff in there during the runtime are rather limited
With all this in mind:
If you want to create SomeContext like you do in the controller, its not managed by spring, so you can't use Injection of spring as is into the builder.
The builder is a singleton, so if you inject it with a regular #Autowire into another singleton (SomeService in your case), you'll have to deal with the same instance of the builder object - think about concurrent access to the method run of SomeService and you'll understand that this solution is not really a good one.
So these are the "inaccuracies" in the presented solution.
Now, in terms of solution, you can:
Option 1
Don't manage builders in Spring, not everything should be managed by spring, in this case you'll keep your code as it is now.
Option 2
and this is a the solution, although pretty advanced one:
Use Java Configuration to create prototype beans in runtime with an ability to inject parameters into the bean.
Here is an example:
// Note, I've removed all the annotations, I'll use java configurations for that, read below...
public class SomeBuilder {
private final SomeContext ctx;
public SomeBuilder(SomeContext ctx) {
this.ctx = ctx;
}
public void test() {
System.out.println("ctx name: " + ctx.getName());
}
}
Now the class SomeService will also slightly change:
public class SomeService {
private Function<SomeContext, SomeBuilder> builderFactory;
public void run(SomeContext ctx) {
SomeBuilder someBuilder = builderFactory.apply(ctx);
someBuilder.test();
}
}
And now you should "glue" it to spring in an advanced way with Java Configurations:
#Configuration
public class MyConfiguration {
#Bean
public Function<SomeContext, SomeBuilder> builderFactory() {
return ctx -> someBuilder(ctx);
}
#Bean
#Scope(value = "prototype")
public SomeBuilder someBuilder(SomeContext ctx) {
return new SomeBuilder(ctx);
}
#Bean
public SomeService someService() {
return new SomeService(builderFactory());
}
}
For more details with a really similar example, see this tutorial

Injecting a single Spring bean instance into a static variable of a utility class

I have this web application built with Spring and Vaadin, in which I wanted to do this, for the sake of convenience:
Create a utility class that wraps a Spring service, and allows the use of its static methods throughout the application, without having to worry about injecting this service everywhere, like so:
String configurationValue = ConfigurationUtil.getString("some.property.key");
If you work with Vaadin, you might see how convenient this is, because the whole presentation layer is written in Java and you can't always inject Spring services into your Vaadin components as these Vaadin components are not always Spring components themselves.
So this is my utility class:
public final class ConfigurationUtil {
// this is the spring service:
private static ConfigurationService configurationService;
public static void setConfigurationService(final ConfigurationService configurationService) {
ConfigurationUtil.configurationService = configurationService;
}
public static String getString(final String key) {
return configurationService.getString(key);
}
}
This is my service:
#Service("configurationService")
public class ConfigurationServiceImpl implements ConfigurationService, BeanFactoryAware {
private final FrameworkService frameworkService;
#Autowired
public ConfigurationServiceImpl(final FrameworkService frameworkService) throws IOException, ConfigurationException {
// this is where I set this service bean to the utility class
ConfigurationUtil.setConfigurationService(this);
this.frameworkService = frameworkService;
}
public String getString(String key) {
// code that retrieves a configuration value from our configuration files
}
}
My question here is: I'm a bit worried about this causing a bottleneck to access the configuration service, as multiple threads will be calling it, from multiple user sessions. Would this be a problem? Please explain why. Also, feel free to point out other problems with this solution.

I suggest to create a bean that implements ApplicationContextAware like this:
#Component
public class ApplicationContextProvider implements ApplicationContextAware {
private static ApplicationContext context;
#Override
public void setApplicationContext(ApplicationContext ac) {
context = ac;
}
public static String getString(final String key) {
ConfigurationService configurationService = context.getBean(ConfigurationService.class);
return configurationService.getString(key);
}
public static <T> T bean(Class<T> beanType) {
return context.getBean(beanType);
}
}
You can create a method like in the example to give static access to Spring Beans or what you requested to get a String from your ConfigurationService.
Btw. I use this a lot in Vaadin applications because I don't want to make every component a Spring Bean.

How to assign a value from application.properties to a static variable?

I am using Spring MVC. I have a UserService class annotated with #Service that has a lot of static variables. I would like to instantiate them with values from the application.properties file.
For example in application.properties I have: SVN_URL = http://some.url/repositories
Then in the class there is: #Value("${SVN_URL}") private static String SVN_URL
I get the Instantiation of bean failed; nested exception is java.lang.ExceptionInInitializerError
I have also tried #Autowired private static Environment env;
And then: private static String SVN_URL=env.getProperty("SVN_URL");
It gives the same error.

Think about your problem for a second. You don't have to keep any properties from application.properties in static fields. The "workaround" suggested by Patrick is very dirty:
you have no idea when this static field is modified
you don't know which thread modifies it's value
any thread at any time can change value of this static field and you are screwed
initializing private static field that way has no sense to me
Keep in mind that when you have bean controlled by #Service annotation you delegate its creation to Spring container. Spring controls this bean lifecycle by creating only one bean that is shared across the whole application (of course you can change this behavior, but I refer to a default one here). In this case any static field has no sense - Spring makes sure that there is only one instance of UserService. And you get the error you have described, because static fields initialization happens many processor-cycles before Spring containers starts up. Here you can find more about when static fields are initialized.
Suggestion
It would be much better to do something like this:
#Service
public class UserService {
private final String svnUrl;
#Autowired
public UserService(#Value("${SVN_URL}") String svnUrl) {
this.svnUrl = svnUrl;
}
}
This approach is better for a few reasons:
constructor injection describes directly what values are needed to initialize the object
final field means that this value wont be changed after it gets initialized in a constructor call (you are thread safe)
Using #ConfigurationProperties
There is also another way to load multiple properties to a single class. It requires using prefix for all values you want to load to your configuration class. Consider following example:
#ConfigurationProperties(prefix = "test")
public class TestProperties {
private String svnUrl;
private int somePort;
// ... getters and setters
}
Spring will handle TestProperties class initialization (it will create a testProperties bean) and you can inject this object to any other bean initialized by Spring container. And here is what exemplary application.properties file look like:
test.svnUrl=https://svn.localhost.com/repo/
test.somePort=8080
Baeldung created a great post on this subject on his blog, I recommend reading it for more information.
Alternative solution
If you need somehow to use values in static context it's better to define some public class with public static final fields inside - those values will be instantiated when classloader loads this class and they wont be modified during application lifetime. The only problem is that you won't be able to load these values from Spring's application.properties file, you will have to maintain them directly in the code (or you could implement some class that loads values for these constants from properties file, but this sounds so verbose to the problem you are trying to solve).

Spring does not allow to inject value into static variables.
A workaround is to create a non static setter to assign your value into the static variable:
#Service
public class UserService {
private static String SVN_URL;
#Value("${SVN_URL}")
public void setSvnUrl(String svnUrl) {
SVN_URL = svnUrl;
}
}

Accessing application.properties in static member functions is not allowed but here is a work around,
application.properties
server.ip = 127.0.0.1
PropertiesExtractor.java
public class PropertiesExtractor {
private static Properties properties;
static {
properties = new Properties();
URL url = new PropertiesExtractor().getClass().getClassLoader().getResource("application.properties");
try{
properties.load(new FileInputStream(url.getPath()));
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
public static String getProperty(String key){
return properties.getProperty(key);
}
}
Main.class
public class Main {
private static PropertiesExtractor propertiesExtractor;
static{
try {
propertiesExtractor = new PropertiesExtractor();
} catch (UnknownHostException e) {
e.printStackTrace();
}
}
public static getServerIP(){
System.out.println(propertiesExtractor.getProperty("server.ip")
}
}

static String profile;
#Value("${spring.profiles.active:Unknown}")
private void activeProfile(String newprofile) {
profile = newprofile;
};

In order to gain static access to Spring Boot properties you can create a Properties Holder Component which implements the Command Line Runner interface. The command line runner interface executes run() upon component instantiation by Spring Boot.
Since we have autowired access to our properties object in the PropertiesHolder component, it is possible to assign the autowired properties to a static Properties class variable upon CommandLineRunner execution of the run() method.
At this point any class can statically call PropertiesHolder.getProperties() to access the contents of Spring Boot properties values.
PropertiesHolder.class:
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.stereotype.Component;
#Component
public class PropertiesHolder implements CommandLineRunner {
//Spring Boot Autowired Properties Object
#Autowired MyProperties myAutowiredProperties;
//Statically assigned Properties Object
private static MyProperties properties;
//Hide constructor (optional)
private PropertiesHolder(){}
public static MyProperties getProperties() throws NullPointerException{
if(PropertiesHolder.properties == null)
throw new NullPointerException("Properites have not been initialized by Spring Application before call.");
return PropertiesHolder.properties;
}
//Use to assign autowired properties to statically allocated properties
public static void makeAvailable(MyProperties myAutowiredProperties){
PropertiesHolder.properties = myAutowiredProperties;
}
//Spring Boot command line runner autoexecuted upon component creation
//which initializes the static properties access
public void run(String... args) {
PropertiesHolder.makeAvailable(myAutowiredProperties);
}
}
MyProperties.class
import lombok.Data;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Configuration;
import org.springframework.stereotype.Component;
//Example: your_properties_file_prefix.properties
#ConfigurationProperties(prefix = "YOUR_PROPERTIES_FILE_PREFIX")
#Component
#Data
public class MyProperties {
private String property1;
private String property2;
private String property3;
}

At least one more simple solution with configuration file:
#Configuration
public class YourStaticPropertyConfiuration {
public static String PROPERTY_NAME;
#Value("${propertyName}")
public void setProperty(final String propertyName) {
PROPERTY_NAME = propertyName;
}
}
Use PROPERTY_NAME anywhere as static variable

For all those who, for whatever reason, want to provide setting properties imported from files as static properties, here is a solution that is as simple and safe as possible.
The Problem:
Spring Boot unfortunately doesn't provide a simple way to import properties from a file and bind them as static properties to a class. One possible solution to achieve that anyway would be to set the static properties using `#Value` annotations like this:
public class GlobalProperties {
public static String NAME;
#Value("${configs.boss.name}")
public void setName(String name) {
NAME = name;
}
}
However, this approach would mean that the static properties cannot be declared as final.And we certainly don't want that.
The Solution:
application.yml:
configs:
boss:
name: "Leeloo Multipass"
ConfigProperties.java:
#Validated
#ConfigurationProperties(prefix = "configs")
public record ConfigProperties(#NotNull Boss boss) {
public static final String BOSS_NAME = BOSS.NAME;
private static class Boss {
private static String NAME;
public Boss(String name) {
NAME = name;
}
}
}
The solution is based on the assumption that Spring Boot builds the configuration objects first, and the properties' configuration objects first of all. So at the time Spring Boot adds the prepared objects as Bean to the context, the nested classes are already setup and the static properties initialization of ConfigProperties can access the static properties of the nested classes (which still are not final, but also not accessible from outside). This way it is possible to provide all properties declared as static final. Unless Spring Boot doesn't decide to change its internal initialization process, everything is cream & cookie.
This approach was tested with Spring Boot 3 and Java 17. It is of course possible to provide the properties additionally via the configs-bean. For that, the properties of the nested classes must be explicitly specified and their corresponding getters must be implemented. In this case, some simplification can be achieved by using records instead of classes.

Inject spring bean dynamically

In a java-spring web-app I would like to be able to dynamically inject beans.
For example I have an interface with 2 different implementations:
In my app I'm using some properties file to configure injections:
#Determines the interface type the app uses. Possible values: implA, implB
myinterface.type=implA
My injections actually loaded conditionally relaying on the properties values in the properties file. For example in this case myinterface.type=implA wherever I inject MyInterface the implementation that will be injected will be ImplA (I accomplished that by extending the Conditional annotation).
I would like that during runtime - once the properties are changed the following will happen (without server restart):
The right implementation will be injected. For example when setting myinterface.type=implB ImplB will be injected where-ever MyInterface is used
Spring Environment should be refreshed with the new values and re-injected as well to beans.
I thought of refreshing my context but that creates problems.
I thought maybe to use setters for injection and re-use those setters once properties are re-configured. Is there a working practice for such a requirement?
Any ideas?
UPDATE
As some suggested I can use a factory/registry that holds both implementations (ImplA and ImplB) and returns the right one by querying the relevant property.
If I do that I still have the second challenge - the environment. for example if my registry looks like this:
#Service
public class MyRegistry {
private String configurationValue;
private final MyInterface implA;
private final MyInterface implB;
#Inject
public MyRegistry(Environmant env, MyInterface implA, MyInterface ImplB) {
this.implA = implA;
this.implB = implB;
this.configurationValue = env.getProperty("myinterface.type");
}
public MyInterface getMyInterface() {
switch(configurationValue) {
case "implA":
return implA;
case "implB":
return implB;
}
}
}
Once property has changed I should re-inject my environment. any suggestions for that?
I know I can query that env inside the method instead of constructor but this is a performance reduction and also I would like to think of an ider for re-injecting environment (again, maybe using a setter injection?).

I would keep this task as simple as possible. Instead of conditionally load one implementation of the MyInterface interface at startup and then fire an event that triggers dynamic loading of another implementation of the same interface, I would tackle this problem in a different way, that is much simpler to implement and maintain.
First of all, I'd just load all possible implementations:
#Component
public class MyInterfaceImplementationsHolder {
#Autowired
private Map<String, MyInterface> implementations;
public MyInterface get(String impl) {
return this.implementations.get(impl);
}
}
This bean is just a holder for all implementations of the MyInterface interface. Nothing magic here, just common Spring autowiring behavior.
Now, wherever you need to inject a specific implementation of MyInterface, you could do it with the help of an interface:
public interface MyInterfaceReloader {
void changeImplementation(MyInterface impl);
}
Then, for every class that needs to be notified of a change of the implementation, just make it implement the MyInterfaceReloader interface. For instance:
#Component
public class SomeBean implements MyInterfaceReloader {
// Do not autowire
private MyInterface myInterface;
#Override
public void changeImplementation(MyInterface impl) {
this.myInterface = impl;
}
}
Finally, you need a bean that actually changes the implementation in every bean that has MyInterface as an attribute:
#Component
public class MyInterfaceImplementationUpdater {
#Autowired
private Map<String, MyInterfaceReloader> reloaders;
#Autowired
private MyInterfaceImplementationsHolder holder;
public void updateImplementations(String implBeanName) {
this.reloaders.forEach((k, v) ->
v.changeImplementation(this.holder.get(implBeanName)));
}
}
This simply autowires all beans that implement the MyInterfaceReloader interface and updates each one of them with the new implementation, which is retrieved from the holder and passed as an argument. Again, common Spring autowiring rules.
Whenever you want the implementation to be changed, you should just invoke the updateImplementations method with the name of the bean of the new implementation, which is the lower camel case simple name of the class, i.e. myImplA or myImplB for classes MyImplA and MyImplB.
You should also invoke this method at startup, so that an initial implementation is set on every bean that implements the MyInterfaceReloader interface.

I solved a similar issue by using org.apache.commons.configuration.PropertiesConfiguration and org.springframework.beans.factory.config.ServiceLocatorFactoryBean:
Let VehicleRepairService be an interface:
public interface VehicleRepairService {
void repair();
}
and CarRepairService and TruckRepairService two classes that implements it:
public class CarRepairService implements VehicleRepairService {
#Override
public void repair() {
System.out.println("repair a car");
}
}
public class TruckRepairService implements VehicleRepairService {
#Override
public void repair() {
System.out.println("repair a truck");
}
}
I create an interface for a service factory:
public interface VehicleRepairServiceFactory {
VehicleRepairService getRepairService(String serviceType);
}
Let use Config as configuration class:
#Configuration()
#ComponentScan(basePackages = "config.test")
public class Config {
#Bean
public PropertiesConfiguration configuration(){
try {
PropertiesConfiguration configuration = new PropertiesConfiguration("example.properties");
configuration
.setReloadingStrategy(new FileChangedReloadingStrategy());
return configuration;
} catch (ConfigurationException e) {
throw new IllegalStateException(e);
}
}
#Bean
public ServiceLocatorFactoryBean serviceLocatorFactoryBean() {
ServiceLocatorFactoryBean serviceLocatorFactoryBean = new ServiceLocatorFactoryBean();
serviceLocatorFactoryBean
.setServiceLocatorInterface(VehicleRepairServiceFactory.class);
return serviceLocatorFactoryBean;
}
#Bean
public CarRepairService carRepairService() {
return new CarRepairService();
}
#Bean
public TruckRepairService truckRepairService() {
return new TruckRepairService();
}
#Bean
public SomeService someService(){
return new SomeService();
}
}
By using FileChangedReloadingStrategy your configuration be reload when you change the property file.
service=truckRepairService
#service=carRepairService
Having the configuration and the factory in your service, let you can get the appropriate service from the factory using the current value of the property.
#Service
public class SomeService {
#Autowired
private VehicleRepairServiceFactory factory;
#Autowired
private PropertiesConfiguration configuration;
public void doSomething() {
String service = configuration.getString("service");
VehicleRepairService vehicleRepairService = factory.getRepairService(service);
vehicleRepairService.repair();
}
}
Hope it helps.

If I understand you correctly then the goal is not to replace injected object instances but to use different implementations during interface method call depends on some condition at run time.
If it is so then you can try to look at the Sring TargetSource mechanism in combination with ProxyFactoryBean. The point is that proxy objects will be injected to beans that uses your interface, and all the interface method calls will be sent to TargetSource target.
Let's call this "Polymorphic Proxy".
Have a look at example below:
ConditionalTargetSource.java
#Component
public class ConditionalTargetSource implements TargetSource {
#Autowired
private MyRegistry registry;
#Override
public Class<?> getTargetClass() {
return MyInterface.class;
}
#Override
public boolean isStatic() {
return false;
}
#Override
public Object getTarget() throws Exception {
return registry.getMyInterface();
}
#Override
public void releaseTarget(Object target) throws Exception {
//Do some staff here if you want to release something related to interface instances that was created with MyRegistry.
}
}
applicationContext.xml
<bean id="myInterfaceFactoryBean" class="org.springframework.aop.framework.ProxyFactoryBean">
<property name="proxyInterfaces" value="MyInterface"/>
<property name="targetSource" ref="conditionalTargetSource"/>
</bean>
<bean name="conditionalTargetSource" class="ConditionalTargetSource"/>
SomeService.java
#Service
public class SomeService {
#Autowired
private MyInterface myInterfaceBean;
public void foo(){
//Here we have `myInterfaceBean` proxy that will do `conditionalTargetSource.getTarget().bar()`
myInterfaceBean.bar();
}
}
Also if you want to have both MyInterface implementations to be Spring beans, and the Spring context could not contains both instances at the same time then you can try to use ServiceLocatorFactoryBean with prototype target beans scope and Conditional annotation on target implementation classes. This approach can be used instead of MyRegistry.
P.S.
Probably Application Context refresh operation also can do what you want but it can cause other problems such as performance overheads.

This may be a duplicate question or at least very similar, anyway I answered this sort of question here: Spring bean partial autowire prototype constructor
Pretty much when you want a different beans for a dependency at run-time you need to use a prototype scope. Then you can use a configuration to return different implementations of the prototype bean. You will need to handle the logic on which implementation to return yourself, (they could even be returning 2 different singleton beans it doesn't matter) But say you want new beans, and the logic for returning the implementation is in a bean called SomeBeanWithLogic.isSomeBooleanExpression(), then you can make a configuration:
#Configuration
public class SpringConfiguration
{
#Bean
#Autowired
#Scope("prototype")
public MyInterface createBean(SomeBeanWithLogic someBeanWithLogic )
{
if (someBeanWithLogic .isSomeBooleanExpression())
{
return new ImplA(); // I could be a singleton bean
}
else
{
return new ImplB(); // I could also be a singleton bean
}
}
}
There should never be a need to reload the context. If for instance, you want the implementation of a bean to change at run-time, use the above. If you really need to reload your application, because this bean was used in constructors of a singleton bean or something weird, then you need to re-think your design, and if these beans are really singleton beans. You shouldn't be reloading the context to re-create singleton beans to achieve different run-time behavior, that is not needed.
Edit The first part of this answer answered the question about dynamically injecting beans. As asked, but I think the question is more of one: 'how can I change the implementation of a singleton bean at run-time'. This could be done with a proxy design pattern.
interface MyInterface
{
public String doStuff();
}
#Component
public class Bean implements MyInterface
{
boolean todo = false; // change me as needed
// autowire implementations or create instances within this class as needed
#Qualifier("implA")
#Autowired
MyInterface implA;
#Qualifier("implB")
#Autowired
MyInterface implB;
public String doStuff()
{
if (todo)
{
return implA.doStuff();
}
else
{
return implB.doStuff();
}
}
}

You can use #Resource annotation for injection as originally answered here
e.g.
#Component("implA")
public class ImplA implements MyInterface {
...
}
#Component("implB")
public class ImplB implements MyInterface {
...
}
#Component
public class DependentClass {
#Resource(name = "\${myinterface.type}")
private MyInterface impl;
}
and then set the implementation type in properties file as -
myinterface.type=implA

Be aware that - if interesting to know about - FileChangedReloadingStrategy makes your project highly dependent on the deployment conditions: the WAR/EAR should be exploded by container and your should have direct access to the file system, conditions that are not always met in all situations and environments.

You can use Spring #Conditional on a property value. Give both Beans the same name and it should work as only one Instance will be created.
Have a look here on how to use #Conditional on Services and Components:
http://blog.codeleak.pl/2015/11/how-to-register-components-using.html

public abstract class SystemService {
}
public class FooSystemService extends FileSystemService {
}
public class GoSystemService extends FileSystemService {
}
#Configuration
public class SystemServiceConf {
#Bean
#Conditional(SystemServiceCondition.class)
public SystemService systemService(#Value("${value.key}") value) {
switch (value) {
case A:
return new FooSystemService();
case B:
return new GoSystemService();
default:
throw new RuntimeException("unknown value ");
}
}
}
public class SystemServiceCondition implements Condition {
#Override
public boolean matches(ConditionContext conditionContext, AnnotatedTypeMetadata annotatedTypeMetadata) {
return true;
}
}

How to #autowire some bean into JsonSerializer?

I am using lazy loading with hibernate in my web app.
I would like to load some objects from the database at the parsing stage of the server response
#Component
public class DesignSerializer extends JsonSerializer<Design> {
#Autowired
IDesignService designService; <-- is null
}
Which is totally understandable because DesignSerializer is being instantiated with the "new" operator for each object.
I am sure there is a way to inject my bean into that serializer when ever it is created, I just don't know how.
Can you guys help me or point me in the right direction.

Solution is SpringBeanAutowiringSupport if you are using Spring Framework 2.5+.
public class DesignSerializer extends JsonSerializer<Design> {
#Autowired
IDesignService designService;
}
public DesignSerializer(){
SpringBeanAutowiringSupport.processInjectionBasedOnCurrentContext(this);
}
...
}
I Hope that help you

We had the same problem with JsonSerializer and Spring autowiring. The solution that worked for us was to make two constructors. One for Spring which sets the dependency as a static field, and another one that is used by the Jackson initialisation.
This works because the Spring dependency injection (autowiring) happens before Jackson initialises the serializer.
#Component
public class MyCustomSerializer extends JsonSerializer<String> {
private static IDesignService designService;
// Required by Jackson annotation to instantiate the serializer
public MyCustomSerializer() { }
#Autowired
public MyCustomSerializer(IDesignService designService) {
this.designService = designService;
}
#Override
public void serialize(String m, JsonGenerator gen, SerializerProvider s) {
gen.writeObject(MyCustomSerializer.designService.method(..));
}
}

I Solved the problem by creating a static field in a different bean and then #Autowire its setter method.
#Service("ToolBox")
#Transactional
public class ToolBox
{
static Logger logger = Logger.getLogger(ToolBox.class);
private static IService service;
#Autowired
public void setService(IService service)
{
ToolBox.service = service;
}
public static IService getService()
{
return ToolBox.service;
}}
like shown in this thread: Can you use #Autowired with static fields?