hibernate - 使用 Hibernate Mapping 不使用 Hibernate Annotations 从 postgres 读取 Blob

Question

当我使用 Hibernate Mapping 时，如何从数据库中读取 blob。我可以将图像保存在数据库中。但是读取数据库中的 blob 字段会产生问题。你能指导我在不使用 Hibernate 注释的情况下逐步从 postgres 数据库中读取 blob。我正在使用休眠映射。

Answer 1

创建这样的实体

@Entity
@Table(name = "core_file")
@SequenceGenerator(name = "default_gen", sequenceName = "seq_core_file", allocationSize = 1)
public class FileProvider extends BaseEntity<Long> {

    @Column(name = "attachment", nullable = false)
    private byte[]  attachment;

    @Column(name = "file_Name")
    private String  fileName;

    @Column(name = "file_Type", nullable = false)
    private String  mimeType;

    @Column(name = "file_Code", nullable = false)
    private String  fileCode;

    @Column(name = "accept_date")
    private String  acceptDate;



    public FileProvider() {
        super();
    }

    public FileProvider(byte[] attachment, String fileName, String mimeType) {
        super();
        this.attachment = attachment;
        this.fileName = fileName;
        this.mimeType = mimeType;
    }

    public byte[] getAttachment() {
        return attachment;
    }

    public void setAttachment(byte[] attachment) {
        this.attachment = attachment;
    }

    public String getFileName() {
        return fileName;
    }

    public void setFileName(String fileName) {
        this.fileName = fileName;
    }

    public String getMimeType() {
        return mimeType;
    }

    public void setMimeType(String mimeType) {
        this.mimeType = mimeType;
    }

    public String getFileCode() {
        return fileCode;
    }

    public void setFileCode(String fileCode) {
        this.fileCode = fileCode;
    }

    public String getAcceptDate() {
        return acceptDate;
    }

    public void setAcceptDate(String acceptDate) {
        this.acceptDate = acceptDate;
    }

}