REST Web Services Blob download

[bkraut]

Hi I'm using REST WebServices to publish Update objects to the server. These are stored into the database. Here is Update entity:

import java.sql.Blob;
import java.util.Date;

import javax.persistence.Basic;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.Id;
import javax.persistence.Lob;
import javax.persistence.Table;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;
import javax.xml.bind.annotation.XmlRootElement;

@Entity
@Table(name="Sys_Update")
@XmlRootElement(name="update")
public class Update {
    
    @Id 
    @Column(name = "uuid") 
    private String uuid = null;
    
    @NotNull
    @Size(min = 1, max = 10)
    @Column(name = "version", length=10, nullable=false)
    private String version;
    
    @NotNull
    @Size(min = 1, max = 30)
    @Column(name = "author", length=30, nullable=false)
    private String author;
    
    @NotNull
    @Size(min = 1, max = 100)
    @Column(name = "fileName", length=100, nullable=false)
    private String fileName;
    
    @Size(max = 5000)
    @Column(name = "description", length=5000)
    private String description;
    
    @NotNull
    @Column(name = "size", nullable=false)
    private Long size;
 
    @Lob
    @NotNull
    @Basic(fetch = FetchType.LAZY)
    @Column(name="data", nullable=false)
    private Blob data;
    
    @Column(name = "creationDate", nullable=false)
    private Date creationDate;
    
    @Column(name = "publishDate")
    private Date publishDate;
    
    public String getUuid() {
        return uuid;
    }
    public void setUuid(String uuid) {
        this.uuid = uuid;
    }
    public String getVersion() {
        return version;
    }
    public void setVersion(String version) {
        this.version = version;
    }
    public String getAuthor() {
        return author;
    }
    public void setAuthor(String author) {
        this.author = author;
    }
    
    public Date getPublishDate() {
        return publishDate;
    }
    
    public void setPublishDate(Date publishDate) {
        this.publishDate = publishDate;
    }
    public Date getCreationDate() {
        return creationDate;
    }
    public void setCreationDate(Date creationDate) {
        this.creationDate = creationDate;
    }
    public String getFileName() {
        return fileName;
    }
    public void setFileName(String fileName) {
        this.fileName = fileName;
    }
    public Long getSize() {
        return size;
    }
    public void setSize(Long size) {
        this.size = size;
    }
    public Blob getData() {
        return data;
    }
    public void setData(Blob data) {
        this.data = data;
    }
    public String getDescription() {
        return description;
    }
    public void setDescription(String description) {
        this.description = description;
    }
} 

I can successfully publish updates to the database, but I do not know, how to download them to the client.

I'd like to get a List of updates from the server.

This is my server method which is not working:

@SuppressWarnings("unchecked")
    public UpdateList getAll(String localisation) throws Exception {
        DetachedCriteria criteria = DetachedCriteria.forClass(Update.class, "update").addOrder(Order.desc("publishDate"));
        List<Update> updates = this.hibernateTemplate.findByCriteria(criteria);
        UpdateList updateList = new UpdateList();
        updateList.setData(updates);
        return updateList; 
    } 

Of course the Blob field fails. How can I successfully do that? Any help or directions appreciated.

Tnx,
Bojan