How can I retrieve a JDBC ResultSet as an ArrayList?

Question

I\'m doing a query to retrieve a large amount of IDs (integers). Instead of iterating millions of times through the ResultSet and copying everything one-by-one to an ArrayLi

Answer 1

Put the code in a method. It's very simple to call methods...

Off the top of my head:

public static List readInts(
     PreparedStatement statement
) throws SQLException {
     ResultSet results = statement.executeQuery();
     try {
         assert results.getMetaData().getColumnCount() == 1;

         List ints = new ArrayList();
         while (results.next()) {
             ints.add(Integer.valueOf(results.getInt(1)));
         }
         return ints;
     } finally {
         results.close();
     }
}

Then just call it as:

List ids = readInts(myStatemnet);

Done.