我似乎无法弄清楚如何使父类参数可用于规范查询。如果我使用 RoleDAO
参数进行查询name
那么我会得到一个结果,但如果我尝试按数据库中存在的BaseDAO
值的 id
进行搜索,则不会返回任何内容。
另一方面,如果我将id
参数移动到RoleDAO
则搜索工作正常。
实体如下所示:
@EqualsAndHashCode(callSuper = true)
@Data
@Entity
@Table(name = "user_role", indexes = {
@Index(name = "id_index", columnList = "id"),
@Index(name = "name_index", columnList = "name"),
})
public class RoleDAO extends BaseDAO {
@NotEmpty(message = "{error.not-empty}")
@Column
private String name;
}
基础道:
@MappedSuperclass
@Data
public class BaseDAO implements Serializable {
private static final long serialVersionUID = 1;
@Id
@GenericGenerator(name = "uuid", strategy = "uuid2")
@GeneratedValue(generator = "uuid")
@Column(name = "id", unique = true, nullable = false)
private String id;
@NotNull(message = "{error.not-null}")
@Column(name = "created")
private LocalDateTime created;
@NotEmpty(message = "{error.not-empty}")
@Size(max = 200, message = "{error.max}")
@Column(name = "created_by")
private String createdBy;
@Column(name = "modified")
private LocalDateTime modified;
@Size(max = 200, message = "{error.max}")
@Column(name = "modified_by")
private String modifiedBy;
@PrePersist
public void prePersist() {
id = UUID.randomUUID().toString();
created = LocalDateTime.now();
}
@PreUpdate
public void preUpdate() {
modified = LocalDateTime.now();
}
}
规范:
public class Specifications<T> {
public Specification<T> containsTextInAttributes(String text, List<String> attributes) {
if (!text.contains("%")) {
text = "%" + text + "%";
}
String finalText = text;
return (root, query, builder) -> builder.or(root.getModel().getDeclaredSingularAttributes().stream()
.filter(a -> attributes.contains(a.getName()))
.map(a -> builder.like(root.get(a.getName()), finalText))
.toArray(Predicate[]::new));
}
}
然后有一个带有方法的存储库:
List<RoleDAO> findAll(Specification<RoleDAO> spec);
以及如何在服务中调用它:
var roles = repository.findAll(
Specification.where(new Specifications<RoleDAO>().containsTextInAttributes(searchTerm, Arrays.asList(ID, NAME)))
);
解决方案非常简单:
public class Specifications<T> {
public Specification<T> containsTextInAttributes(String text, List<String> attributes) {
if (!text.contains("%")) {
text = "%" + text + "%";
}
String finalText = text;
return (root, query, builder) -> builder.or(root.getModel().getSingularAttributes().stream()
.filter(a -> attributes.contains(a.getName()))
.map(a -> builder.like(root.get(a.getName()), finalText))
.toArray(Predicate[]::new));
}
}
请注意getSingularAttributes()
调用更改。