对Class<T>的unChecked调用

Question

public class UserHeaderRepository<TEntity>{

  private final CollectionReference collectionReference;

  private final Class<TEntity> entityClass;

  public static UserHeaderRepository getInstance()
  {          

     return new UserHeaderRepository(UserHeader.class);
  }

  public UserHeaderRepository ( Class < TEntity > entityClass ) {

    this.entityClass = entityClass;
    FirebaseFirestore db = FirebaseFirestore.getInstance();
    this.collectionReference = db.collection("global_community");
 }

我不知道为什么会出现以下错误：

unchecked call to  UserHeaderRepository(Class<TEntity>)  row type 'as a member of raw type  '../appRepository/UserHeaderRepository'

Answer 1

您是using raw types where you were supposed to use the parameterized type，请将getInstance方法更改为以下内容，

public static UserHeaderRepository<UserHeader> getInstance() {
    return new UserHeaderRepository<>(UserHeader.class);
}

此外，它不应该是一个错误，它应该是来自编译器的警告。