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There is a newer version: 8.6.0.37351

Field injection seems like a tidy way to get your classes what they need to do their jobs, but it's really a NullPointerException waiting to happen unless all your class constructors are private. That's because any class instances that are constructed by callers, rather than instantiated by the Spring framework, won't have the ability to perform the field injection.
Instead @Inject should be moved to the constructor and the fields required as constructor parameters.
This rule raises an issue when classes with non-private constructors (including the default constructor) use field injection.

Noncompliant Code Example
class MyComponent {  // Anyone can call the default constructor 
 
  @Inject MyCollaborator collaborator;  // Noncompliant
  
  public void myBusinessMethod() {
    collaborator.doSomething();  // this will fail in classes new-ed by a caller
  }
}


Compliant Solution
class MyComponent {
 
  private final MyCollaborator collaborator;
  
  @Inject
  public MyComponent(MyCollaborator collaborator) {
    Assert.notNull(collaborator, "MyCollaborator must not be null!");
    this.collaborator = collaborator;
  }

  public void myBusinessMethod() {
    collaborator.doSomething();
  }
}