Decoding blob data from a sqlite database into a human readable text

问题

I have a Sqlite database file that has blob data in it. I only know the the database has blob data and I know what the expected output should be. The blob data's expected output should be a Mac address with other text.

I tried getting the hex output but does not really help me with getting the expected output that I know is in the database. I also used a Hex editor and sqlite viewer but only shows gibberish unreadable text.

Here is some code that I tried to get the bytes from the blob data but does not produce the output I expected. Sqlite doesn't have the getBlob function in Java.

if (rs.next()) {
    byte[] buffer = rs.getBytes(1);
    System.out.println(buffer.toString());
}

An expected output from the blob should be :" JOHN A6:44:33:A4:G5:A4 "

Here is a sample Hex dump 0008f473eb41 e8ba3b1c

How can I programattically retrieve the blob data and decode the contents of the blob in sqlite?

回答1:

Right now you are printing a byte[] array toString(). Arrays in Java don't implement in meaningful way.

You can try converting the byte[] array into a String with:

new String(buffer, Charsets.UTF_8)

If this doesn't work use rs.getBinaryStream(1) to get the InputStream representing the value and read it as per this answer.

来源：https://stackoverflow.com/questions/55729744/decoding-blob-data-from-a-sqlite-database-into-a-human-readable-text