Why am I getting \"Could not determine type for: java.util.List\" when using Hibernate\'s @OneToMany annotation?

Could Not Determine Type for List

Problem:

When using Hibernate for data operations, you encounter the error "Could not determine type for: java.util.List." This occurs while defining a One-To-Many relationship between College and Student entities using @OneToMany and @ManyToOne annotations.

Background:

The error arises because Hibernate is unable to determine the type of the collection (List). The annotation should be applied to fields rather than getter methods when using field access strategy, as indicated by the @Id annotation.

Solution:

To resolve the error, modify the @OneToMany annotation in the College class to be applied directly to the field instead of the getter method. Here's the corrected code:

<code class="java">// College.java

@Entity
public class College {
    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    private int collegeId;
    private String collegeName;

    @OneToMany(targetEntity=Student.class, mappedBy="college", fetch=FetchType.EAGER)
    private List<Student> students;

    // Other getters and setters omitted
}</code>

Additional Considerations:

• Double-check the classpath and ensure that the Hibernate dependencies are included.
• Make sure the database table structure aligns with the entity mappings.
• Consider adding @JoinColumn(name="collegeId") to the @ManyToOne annotation in the Student class if the foreign key column in the database has a different name than "collegeId."

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