Question

I’m using eclipselink as JPA Implementation and PostgreSQL and want to store SHA-1 Hashes in the database.
But I’m getting an Exception like this:

Internal Exception: org.postgresql.util.PSQLException: ERROR: invalid byte sequence for encoding “UTF8”: 0x00
Error Code: 0
Call: INSERT INTO mbm_user (USERNAME, PRENAME, LASTNAME, PASSWORD) VALUES (?, ?, ?, ?)
bind => [Hans, null, null, THE SHA-1 HASH]

THE SHA-1 HASH are some gibberish chars and I can’t paste them here.

My Entity:

@Entity
@Table(name="mbm_user")
public class User extends CanAccessBook{

  @Id @GeneratedValue(strategy=GenerationType.IDENTITY)
  @Column(nullable = false)
  private Long id;

  @Column(nullable = false)
  private String username;

   @Column(nullable = false)
   private String password;

   private String prename;

   private String lastname;
       ...
       ...
}

And the method where I generate the SHA-1 Hash:

    public void setPassword(String password) {
    try {
        MessageDigest md = MessageDigest.getInstance("SHA-1");
        byte[] encryptPassword = md.digest(password.getBytes());
        this.password = new String(encryptPassword);
    } catch (NoSuchAlgorithmException e) {
        e.printStackTrace();
    }
}

How can i avoid the usage of the illegal char 0x00 or is the problem somewhere else?

Answer 1

You are trying to cram a byte[] into a String, which is never going to work well.

1. Persist the SHA-1 hash as a blob. Off the top of my head:

    @Lob
    @Column(nullable = false)
    private byte[] passwordHash;

1. Encode the binary data into a textual representation, either as a hexadecimal string or something like Base64. Google for binaryToHexString or base64encoder, that should put you on the right track.