This code snippet is designed to process BLOB data from...

June 30, 2025 at 04:27 PM

String msg = "";
            try (PreparedStatement psBlob = conn2.prepareStatement("SELECT MESSAGE FROM BOLA WHERE UUID = ?")) {
                psBlob.setString(1, uuid);
                try (ResultSet rs = psBlob.executeQuery()) {
                    if (rs.next()) {
                        msg = readBlob(rs.getBlob(1));
                        String[] lines = msg.split("\\r?\\n");
                        for (int i = 1; i < lines.length; i++) {
                            if (lines[i].contains("\"MessageHeader\"")) {
                                String tbl = extractQuoted(lines[i - 1].trim());
                                blobTables.add(tbl);
                                String keySpec = "";
                                if (i + 11 < lines.length && lines[i + 11].trim().startsWith("\"#text\"")) {
                                    keySpec = extractQuoted(lines[i + 11].trim());
                                }
                                blobKeys.put(tbl, extractKeyValues(lines, tbl, keySpec));
                            }
                        }
                    }
                }
            }

This code snippet is designed to process BLOB data from a database, extract specific information, and store it in maps or collections. Here's a step-by-step explanation:

Initialization:
- An empty string msg is initialized to hold the contents of a BLOB.
- A PreparedStatement is created using the conn2 database connection to execute a SQL query:
```
SELECT MESSAGE FROM BOLA WHERE UUID = ?
```
  This query retrieves the MESSAGE (assumed to be a BLOB) from the BOLA table where the UUID matches the provided uuid value.
Execute the Query:
- The UUID value is set as the query parameter in the PreparedStatement.
- The executeQuery() method is called to run the query, and the results are stored in a ResultSet.
Process the Result:
- If the ResultSet contains a row (rs.next()), the code extracts the BLOB associated with the first column (MESSAGE) using rs.getBlob(1).
- The readBlob method (not shown in the code) is called to process the BLOB and convert it into a string. The resulting string is stored in msg.
- The string is then split into lines using a line separator (msg.split("\\r?\\n")), resulting in an array lines containing individual lines of the BLOB content.
Iterate and Extract Specific Data:
- The code iterates through the lines (starting from the second line, i = 1).
- It looks for lines containing the string "MessageHeader".
- When such a line is found:
  - The table name (tbl) is extracted using the previous line (lines[i - 1].trim()) and a function extractQuoted (assumed to extract quoted parts of a string).
  - blobTables.add(tbl) likely adds the table name to a collection (blobTables is not defined in the snippet but is assumed to be a list or set).
Extract a Related Key and Store Key-Value Pairs:
- If i + 11 is within bounds and lines[i + 11].trim() starts with "\"#text\"", a keySpec is extracted from this line using extractQuoted.
- A map blobKeys (also not defined in the snippet but assumed to be a dictionary) associates the extracted table name (tbl) with specific key-value pairs derived from extractKeyValues(lines, tbl, keySpec).
  - Here, extractKeyValues is another custom function that interprets the lines, table name, and keySpec to generate key-value pairs related to the table.

Summary:

This code:

Retrieves a BLOB (text content) from a database table (BOLA) based on UUID.
Processes the BLOB to extract specific data about "MessageHeader".
Builds:
1. A collection of table names (blobTables).
2. A map of related key-value pairs for these tables (blobKeys).

The extracted information is likely used for further processing or analysis related to "MessageHeader" in the content of the BLOB. The undefined methods (readBlob, extractQuoted, extractKeyValues) are critical to the exact behavior of this code and define how data is interpreted.

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