Odtnhj

I am trying to Autowire a class through constructor.

@Component
public class Test<T extends Something>

@Autowired
public Test(Class<T> entity)
doSomething(enity);

...

When I run the code I keep get the error message

Parameter 0 of constructor in com.test.Test required a bean of type 'java.lang.Class' that could not be found.
Action:
Consider defining a bean of type 'java.lang.Class' in your configuration.

Could someone please tell me where I am going wrong here. Thanks.

It says you that it could not find Class class marked as Bean etc
So you need to have a class wanted to be injected declared as @Bean ,@Component etc.

Here is an example:

@Configuration
 public class Config 

 @Bean
 public<T> Class<T> tClass()
 return (some class to be returned);// you need to generify or pass some type of class which you want 
 

 


 //Here is injecting with no problems
 @Component
 public class Test<T> 

 private Class<T> tClass;

 @Autowired
 public Test(Class<T> tClass) 
 this.tClass = tClass;
 
 

Some how its better do define such architecture which would be better in this case:

 public interface Foo<T> 

 Class<T> getClassFromType();
 

@Component
public class FooIntegerImpl implements Foo<Integer>


 @Override
 public Class<Integer> getClassFromType() 
 return Integer.class;
 


@Component
public class FooStringImpl implements Foo<String>

 @Override
 public Class<String> getClassFromType() 
 return String.class;
 


@Component
public class Test 

 private List<Foo> foo;

 @Autowired
 public Test(List<Foo> foo) 
 this.foo = foo;
 

For such purposes for example you can define generic API which would be common for all cases , actually you can define AbstractCrudOperations and define crud things when someone need to inherit it would define type of object which need to be in and will have some methods defined

Actually in your case i dont know the logic what you want to implement but basic error is that Class could not be found as bean

I think this is helpful for you