51 lines
1.4 KiB
Java
Executable File
51 lines
1.4 KiB
Java
Executable File
package com.ankurm.hibernatedemo.association;
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import jakarta.persistence.CascadeType;
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import jakarta.persistence.Entity;
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import jakarta.persistence.FetchType;
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import jakarta.persistence.GeneratedValue;
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import jakarta.persistence.GenerationType;
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import jakarta.persistence.Id;
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import jakarta.persistence.OneToOne;
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import jakarta.persistence.Table;
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/**
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* Non-owning ("mappedBy") side of an optional {@code @OneToOne}. Docs: 12-association-mappings.md,
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* chapter "The @OneToOne lazy trap". Even though {@link #profile} is declared
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* {@code FetchType.LAZY}, Hibernate cannot build a proxy for it here without bytecode
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* enhancement: it does not hold the foreign key, so it cannot know whether a profile row
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* exists without querying. The result is an eager extra SELECT on every load of LazyUser.
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*/
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@Entity
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@Table(name = "lazy_user")
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public class LazyUser {
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@Id
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@GeneratedValue(strategy = GenerationType.IDENTITY)
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private Long id;
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private String username;
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@OneToOne(mappedBy = "user", fetch = FetchType.LAZY, cascade = CascadeType.ALL, optional = true)
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private LazyProfile profile;
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protected LazyUser() {
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}
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public LazyUser(String username) {
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this.username = username;
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}
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public Long getId() {
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return id;
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}
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public LazyProfile getProfile() {
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return profile;
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}
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public void setProfile(LazyProfile profile) {
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this.profile = profile;
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}
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}
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