We Keep Coding

Why is it not possible to have a generic bean when i have also an Aspect targeting the bean in Spring?

Hi i have a rather specific question regarding Spring Aspects that leaves me puzzled. I played around with Springs and Apsects and and tried out a very simple Example to see how it works:
#Component
public class Comment {
private String text;
private String author;
public String get() {
return text;
}
public void setText(String text) {
this.text = text;
}
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
}
#Aspect
public class LoggingAspect {
#Around("execution(* aop.beans.*.*(..))")
public void log(ProceedingJoinPoint joinPoint) throws Throwable {
System.out.println("Start Aspect for method: " + joinPoint.getSignature());
joinPoint.proceed();
}
}
My configuration file:
#Configuration
#ComponentScan("aop.beans")
#EnableAspectJAutoProxy
public class ProjectConfig {
#Bean
public LoggingAspect aspect() {
return new LoggingAspect();
}
}
With that i used a simple Main method to play around with the concept a little:
public class Main {
public static void main(String[] args) {
#SuppressWarnings("resource")
AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(ProjectConfig.class);
context.registerShutdownHook();
CommentService service = context.getBean(CommentService.class);
Comment comment = context.getBean(Comment.class);
comment.setAuthor("Andreas");
comment.setText("Hallo.");
service.publishComment(comment);
System.out.println(service.getClass());
}
}
This worked fine but something strange happens when ich change the hirarchy of the comment class. I wanted to see what happens if the class implements a generic interface so i changed it as follows
public class Comment implements Supplier<String>
I immediately get an error with the following stack trace:
Exception in thread "main" org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'aop.beans.Comment' available
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBean(DefaultListableBeanFactory.java:351)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBean(DefaultListableBeanFactory.java:342)
at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1172)
at aop.Main.main(Main.java:17)
This left me wondering why that is? If i remove the generic superinterface or the aspect bean everthing works fine but both things together do not seem to fare well. Can someone provide an explanation? Is Spring not able to create a Proxy object if the class has a generic superclass?
Edit: The solution is in the comments :) i found further documentation on the mechanism in Spring Proxy Mechanism Documentation

This happens because of the way Spring implements AOP.
When proxied class (Comment in your case) doesn't implement any interfaces, CGLib proxy is used. Basically, it generates a class which is subclass of proxied class. Thus, you can getBean by parent's class.
When there are implemented interfaces, Spring uses JDK dynamic proxies which don't extend the proxy class, but implement all its interfaces, thus you can't find a bean by it's class.
That's why it's always a good practice to autowire your beans by interface rather then by class.
Solution
You can force Spring to use CGLib proxies for AspectJ by annotating you configuration class #EnableAspectJAutoProxy(proxyTargetClass = true).
If you want to use JDK Dynamic proxies, create interface for Comment and then use context.getBean(YourInterfaceName.class).

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

Call singleton class in spring boot rest api controller

I am new to spring framework. I have to use spring boot and have a rest controller as below :-
#RestController
public class StatisticsController {
private TransactionCache transactionCache;
public StatisticsController(TransactionCache transactionCache) {
this.transactionCache = transactionCache;
}
#PostMapping("/tick")
public ResponseEntity<Object> addInstrumentTransaction(#Valid #RequestBody InstrumentTransaction instrumentTransaction) {
transactionCache.addTransaction(instrumentTransaction);
return new ResponseEntity<>(HttpStatus.CREATED);
}
and I have a class which needs to be singleton :-
#Component
public class TransactionStatisticsCacheImpl implements TransactionCache {
private static TransactionStatisticsCacheImpl instance;
public static TransactionStatisticsCacheImpl getInstance(){
if(Objects.isNull(instance)){
synchronized (TransactionStatisticsCacheImpl.class) {
if(Objects.isNull(instance)){
instance = new TransactionStatisticsCacheImpl();
}
}
}
return instance;
}
private TransactionStatisticsCacheImpl() {}
I want to know the correct way to call this singleton class in my rest controller. I know that by default the scope of a bean in spring is singleton. Is this the correct way to call the singleton class in rest controller?
#RestController
public class StatisticsController {
private TransactionCache transactionCache;
public StatisticsController(TransactionCache transactionCache) {
this.transactionCache = transactionCache;
}
#PostMapping("/tick")
public ResponseEntity<Object> addInstrumentTransaction(#Valid #RequestBody InstrumentTransaction instrumentTransaction) {
transactionCache.addTransaction(instrumentTransaction);
return new ResponseEntity<>(HttpStatus.CREATED);
}
or
We need to call it using the getInstance() method? Also do we need to explicitly have the getInstance method in the TransactionStatisticsCacheImpl class?

One of the major advantages of container injection is that you can get the benefits of singleton semantics without all the serious problems of "hard" singletons (such as difficulty testing). Get rid of the getInstance manual business and let Spring take care of ensuring that a single instance is created and used for the context.

Just for clarification: By default, the spring IOC container will create only one instance per bean definition, unless if you specified otherwise using the #Scope stereotype. But if you create an instance using getInstance() the bean pre-processors and post-processors will not work correctly on that bean definition. And also you can use the #Autowired stereotype to inject a bean definition as needed and if you have different implementations for the same definition you can use the #Qualifier stereotype to specify the implementation that you need to inject, alternatively, you can use the constructor injection to inject your bean definition as needed without auto wiring as mentioned here Spring #Autowire on Properties vs Constructor

I would stick to the answers above. However, if you want to preserve further instantiation of the class in your code (or you want to keep your specific implementation of singleton), you can do it with getInstance().
Firstly, get rid of #Component annotation in your class:
// #Component
public class TransactionStatisticsCacheImpl implements TransactionCache {
private static TransactionStatisticsCacheImpl instance;
public static TransactionStatisticsCacheImpl getInstance(){
if(Objects.isNull(instance)){
synchronized (TransactionStatisticsCacheImpl.class) {
if(Objects.isNull(instance)){
instance = new TransactionStatisticsCacheImpl();
}
}
}
return instance;
}
private TransactionStatisticsCacheImpl() {}
}
Then, you may instantiate your singleton #Bean by defining #Configuration class - this way your bean would get managed by spring container.
#Configuration
public class SingletonConfiguration {
#Bean
public TransactionCache transactionCache() {
return TransactionCacheImpl.getInstance();
}
}
Eventually, you can have your singleton injected in your RestController using #Autowired.
#RestController
public class StatisticsController {
private TransactionCache transactionCache;
#Autowired
public StatisticsController(TransactionCache transactionCache) {
this.transactionCache = transactionCache;
}
#PostMapping("/tick")
public ResponseEntity<Object> addInstrumentTransaction(#Valid #RequestBody InstrumentTransaction instrumentTransaction) {
transactionCache.addTransaction(instrumentTransaction);
return new ResponseEntity<>(HttpStatus.CREATED);
}
}

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;
}
}

Spring Java Config: how do you create a prototype-scoped #Bean with runtime arguments?

Using Spring's Java Config, I need to acquire/instantiate a prototype-scoped bean with constructor arguments that are only obtainable at runtime. Consider the following code example (simplified for brevity):
#Autowired
private ApplicationContext appCtx;
public void onRequest(Request request) {
//request is already validated
String name = request.getParameter("name");
Thing thing = appCtx.getBean(Thing.class, name);
//System.out.println(thing.getName()); //prints name
}
where the Thing class is defined as follows:
public class Thing {
private final String name;
#Autowired
private SomeComponent someComponent;
#Autowired
private AnotherComponent anotherComponent;
public Thing(String name) {
this.name = name;
}
public String getName() {
return this.name;
}
}
Notice name is final: it can only be supplied via a constructor, and guarantees immutability. The other dependencies are implementation-specific dependencies of the Thing class, and shouldn't be known to (tightly coupled to) the request handler implementation.
This code works perfectly well with Spring XML config, for example:
<bean id="thing", class="com.whatever.Thing" scope="prototype">
<!-- other post-instantiation properties omitted -->
</bean>
How do I achieve the same thing with Java config? The following does not work using Spring 3.x:
#Bean
#Scope("prototype")
public Thing thing(String name) {
return new Thing(name);
}
Now, I could create a Factory, e.g.:
public interface ThingFactory {
public Thing createThing(String name);
}
But that defeats the entire point of using Spring to replace the ServiceLocator and Factory design pattern, which would be ideal for this use case.
If Spring Java Config could do this, I would be able to avoid:
defining a Factory interface
defining a Factory implementation
writing tests for the Factory implementation
That's a ton of work (relatively speaking) for something so trivial that Spring already supports via XML config.

In a #Configuration class, a #Bean method like so
#Bean
#Scope("prototype")
public Thing thing(String name) {
return new Thing(name);
}
is used to register a bean definition and provide the factory for creating the bean. The bean that it defines is only instantiated upon request using arguments that are determined either directly or through scanning that ApplicationContext.
In the case of a prototype bean, a new object is created every time and therefore the corresponding #Bean method is also executed.
You can retrieve a bean from the ApplicationContext through its BeanFactory#getBean(String name, Object... args) method which states
Allows for specifying explicit constructor arguments / factory method
arguments, overriding the specified default arguments (if any) in the
bean definition.
Parameters:
args arguments to use if creating a prototype using explicit arguments
to a static factory method. It is invalid to use a non-null args value
in any other case.
In other words, for this prototype scoped bean, you are providing the arguments that will be used, not in the constructor of the bean class, but in the #Bean method invocation. (This method has very weak type guarantees since it uses a name lookup for the bean.)
Alternatively, you can use the typed BeanFactory#getBean(Class requiredType, Object... args) method which looks up the bean by type.
This is at least true for Spring versions 4+.
Note that, if you don't want to start with the ApplicationContext or BeanFactory for your bean retrieval, you can inject an ObjectProvider (since Spring 4.3).
A variant of ObjectFactory designed specifically for injection points,
allowing for programmatic optionality and lenient not-unique handling.
and use its getObject(Object... args) method
Return an instance (possibly shared or independent) of the object
managed by this factory.
Allows for specifying explicit construction arguments, along the lines
of BeanFactory.getBean(String, Object).
For example,
#Autowired
private ObjectProvider<Thing> things;
[...]
Thing newThing = things.getObject(name);
[...]

With Spring > 4.0 and Java 8 you can do this more type-safely:
#Configuration
public class ServiceConfig {
#Bean
public Function<String, Thing> thingFactory() {
return name -> thing(name); // or this::thing
}
#Bean
#Scope(value = "prototype")
public Thing thing(String name) {
return new Thing(name);
}
}
Usage:
#Autowired
private Function<String, Thing> thingFactory;
public void onRequest(Request request) {
//request is already validated
String name = request.getParameter("name");
Thing thing = thingFactory.apply(name);
// ...
}
So now you can get your bean at runtime. This is a factory pattern of course, but you can save some time on writing specific class like ThingFactory (however you will have to write custom #FunctionalInterface to pass more than two parameters).

Since Spring 4.3, there is new way to do it, which was sewed for that issue.
ObjectProvider - It enables you just to add it as a dependency to your "argumented" Prototype scoped bean and to instantiate it using the argument.
Here is a simple example of how to use it:
#Configuration
public class MyConf {
#Bean
#Scope(BeanDefinition.SCOPE_PROTOTYPE)
public MyPrototype createPrototype(String arg) {
return new MyPrototype(arg);
}
}
public class MyPrototype {
private String arg;
public MyPrototype(String arg) {
this.arg = arg;
}
public void action() {
System.out.println(arg);
}
}
#Component
public class UsingMyPrototype {
private ObjectProvider<MyPrototype> myPrototypeProvider;
#Autowired
public UsingMyPrototype(ObjectProvider<MyPrototype> myPrototypeProvider) {
this.myPrototypeProvider = myPrototypeProvider;
}
public void usePrototype() {
final MyPrototype myPrototype = myPrototypeProvider.getObject("hello");
myPrototype.action();
}
}
This will of course print hello string when calling usePrototype.

UPDATED per comment
First, I'm not sure why you say "this does not work" for something that works just fine in Spring 3.x. I suspect something must be wrong in your configuration somewhere.
This works:
-- Config File:
#Configuration
public class ServiceConfig {
// only here to demo execution order
private int count = 1;
#Bean
#Scope(value = "prototype")
public TransferService myFirstService(String param) {
System.out.println("value of count:" + count++);
return new TransferServiceImpl(aSingletonBean(), param);
}
#Bean
public AccountRepository aSingletonBean() {
System.out.println("value of count:" + count++);
return new InMemoryAccountRepository();
}
}
-- Test File to execute:
#Test
public void prototypeTest() {
// create the spring container using the ServiceConfig #Configuration class
ApplicationContext ctx = new AnnotationConfigApplicationContext(ServiceConfig.class);
Object singleton = ctx.getBean("aSingletonBean");
System.out.println(singleton.toString());
singleton = ctx.getBean("aSingletonBean");
System.out.println(singleton.toString());
TransferService transferService = ctx.getBean("myFirstService", "simulated Dynamic Parameter One");
System.out.println(transferService.toString());
transferService = ctx.getBean("myFirstService", "simulated Dynamic Parameter Two");
System.out.println(transferService.toString());
}
Using Spring 3.2.8 and Java 7, gives this output:
value of count:1
com.spring3demo.account.repository.InMemoryAccountRepository#4da8692d
com.spring3demo.account.repository.InMemoryAccountRepository#4da8692d
value of count:2
Using name value of: simulated Dynamic Parameter One
com.spring3demo.account.service.TransferServiceImpl#634d6f2c
value of count:3
Using name value of: simulated Dynamic Parameter Two
com.spring3demo.account.service.TransferServiceImpl#70bde4a2
So the 'Singleton' Bean is requested twice. However as we would expect, Spring only creates it once. The second time it sees that it has that bean and just returns the existing object. The constructor (#Bean method) is not invoked a second time. In deference to this, when the 'Prototype' Bean is requested from the same context object twice we see that the reference changes in the output AND that the constructor (#Bean method) IS invoked twice.
So then the question is how to inject a singleton into a prototype. The configuration class above shows how to do that too! You should pass all such references into the constructor. This will allow the created class to be a pure POJO as well as making the contained reference objects immutable as they should be. So the transfer service might look something like:
public class TransferServiceImpl implements TransferService {
private final String name;
private final AccountRepository accountRepository;
public TransferServiceImpl(AccountRepository accountRepository, String name) {
this.name = name;
// system out here is only because this is a dumb test usage
System.out.println("Using name value of: " + this.name);
this.accountRepository = accountRepository;
}
....
}
If you write Unit Tests you will be ever so happy you created the classes this without all the #Autowired. If you do need autowired components keep those local to the java config files.
This will call the method below in the BeanFactory. Note in the description how this is intended for your exact use case.
/**
* Return an instance, which may be shared or independent, of the specified bean.
* <p>Allows for specifying explicit constructor arguments / factory method arguments,
* overriding the specified default arguments (if any) in the bean definition.
* #param name the name of the bean to retrieve
* #param args arguments to use if creating a prototype using explicit arguments to a
* static factory method. It is invalid to use a non-null args value in any other case.
* #return an instance of the bean
* #throws NoSuchBeanDefinitionException if there is no such bean definition
* #throws BeanDefinitionStoreException if arguments have been given but
* the affected bean isn't a prototype
* #throws BeansException if the bean could not be created
* #since 2.5
*/
Object getBean(String name, Object... args) throws BeansException;

You can achieve a similar effect just by using an inner class:
#Component
class ThingFactory {
private final SomeBean someBean;
ThingFactory(SomeBean someBean) {
this.someBean = someBean;
}
Thing getInstance(String name) {
return new Thing(name);
}
class Thing {
private final String name;
Thing(String name) {
this.name = name;
}
void foo() {
System.out.format("My name is %s and I can " +
"access bean from outer class %s", name, someBean);
}
}
}

If you need to create a qualified bean you can do it this way:
#Configuration
public class ThingConfiguration {
#Bean
#Scope(SCOPE_PROTOTYPE)
public Thing simpleThing(String name) {
return new Thing(name);
}
#Bean
#Scope(SCOPE_PROTOTYPE)
public Thing specialThing(String name) {
Thing thing = new Thing(name);
// some special configuration
return thing;
}
}
// Usage
#Autowired
private ApplicationContext context;
AutowireCapableBeanFactory beanFactory = context.getAutowireCapableBeanFactory();
((DefaultListableBeanFactory) beanFactory).getBean("specialThing", Thing.class, "name");

Late answer with a slightly different approach.
That is a follow up of this recent question that refers this question itself.
Yes, as that was said you can declare the prototype bean that accepts a parameter in a #Configuration class that allows to create a new bean at each injection.
That will make this #Configuration class a factory and to not give this factory too much responsibilities, this should not include other beans.
#Configuration
public class ServiceFactory {
#Bean
#Scope(value = ConfigurableBeanFactory.SCOPE_PROTOTYPE)
public Thing thing(String name) {
return new Thing(name);
}
}
But you can also inject that configuration bean to create Things :
#Autowired
private ServiceFactory serviceFactory;
public void onRequest(Request request) {
//request is already validated
String name = request.getParameter("name");
Thing thing = serviceFactory.thing(name); // create a new bean at each invocation
// ...
}
It is both type-safe and concise.

Nice solutions until now. But I want to post yet another alternative.
Spring has the #Lookup annotation. From javadoc:
An annotation that indicates 'lookup' methods, to be overridden by the
container to redirect them back to the BeanFactory for a getBean call.
you can declare your Thing as prototype bean:
#Component
#Scope(value = ConfigurableBeanFactory.SCOPE_PROTOTYPE)
public class Thing {
#Autowired
private SomeComponent someComponent;
#Autowired
private AnotherComponent anotherComponent;
public Thing(String name) {
this.name = name;
}
}
then you can create instances by creating a method like createThing below in any other bean:
#Controller
public class MyController {
#Autowired
private ApplicationContext appCtx;
public void onRequest(Request request) {
//request is already validated
String name = request.getParameter("name");
Thing thing = createThing(name);
//System.out.println(thing.getName()); //prints name
}
//or public. And can be put in any #Component (including #Configuration)
#Lookup
protected Thing createThing(String name) {
throw new UnsupportedOperationException("Method implemented by Spring.");
}
}

in your beans xml file use the attribute scope="prototype"