CODEWITHSUNDEEP
javamysqlsqljdbc
ROXX STUDIO
ROXX STUDIO

Reputation: 9

Retrieving pictures from MySQL using Java

I have a question related to retrieving files from MySQL using JDBC. I managed to save a .png file from my desktop & retrieve it successfully, but I can't read the file. It shows that the format is unsupported (eventhough I can open the original file without any issue).

Here's the code:

    PreparedStatement ps = con.prepareStatement("select * from project where files IS NOT NULL ");


    ResultSet rs = ps.executeQuery();
    rs.next();

    Clob c = rs.getClob(3);
    Reader r = c.getCharacterStream();


    FileWriter fw = new FileWriter("C:\\Users\\xxxl\\Pictures\\Picture1.png");
    int in;
    while ((in = r.read())!=-1)
        fw.write((char)in);

    fw.close();
    con.close();

    System.out.println("File successfully retrieved");

Any ideas what could be the cause and how to fix it?

Upvotes: 0

Views: 42

Answers (1)

Jens
Jens

Reputation: 69440

You have to use FileOutpuStream, because you have to write bytes not char. Also you column should be a blob.

Something like this should work

PreparedStatement ps = con.prepareStatement("select * from project where files IS NOT NULL ");


ResultSet rs = ps.executeQuery();
rs.next();

Blob c = rs.getBlob(3);
InputStream r = c.getBinaryStream();


FileOutputStream fw = new FileOutputStream ("C:\\Users\\xxxl\\Pictures\\Picture1.png");
int in;
byte[] readBytes = new byte[500];
while (r.read(readBytes)!=-1) {
    fw.write(readBytes);
}
fw.close();
con.close();

System.out.println("File successfully retrieved");

Imports are:

import java.io.FileOutputStream;
import java.io.InputStream;
import java.sql.Blob;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

Upvotes: 1

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