JDBC ResultSet to ArrayList, ArrayList to .txt file - jdbc

Question

I got the following piece of code that retrieves all rows in a table:
String MakeTXT = "USE SRO_VT_SHARD Select * from _RefTeleLink";
pst = conn.prepareStatement(MakeTXT);
rs = pst.executeQuery();
ArrayList<String> links = new ArrayList<>();
int i = 1;
String rows = "";
while (rs.next()) {
for (i = 1; i <= 22; i++) {
links.add(rs.getString(i));
if (i == 22) {
links.add("\n");
}
}
}
rows = String.join("\t", links);
System.out.println(rows);
}
}
What I want to do is:
Select all rows from the table. See result: prnt.sc/egbh4o
Write all selected rows to a .txt file
.txt file has to look something like this (literally copy pasted the rows): http://prntscr.com/egbhn4
What my code currently outputs:
output
It does this because there are 22 columns, and when the loop reaches 22, it adds an enter to the ArrayList.
What I'm actually looking for is a way to copy an entire row using ResultSet, instead of using a for loop to loop 22 times, and make a row of the 22 results.
Have looked everywhere but couldn't find anything.. :(

Answer 1

You do not need an ArrayList to hold the column values as they are read. I'd better use a StringBuilder as show below, concatenating tabs inside the loop and then replacing the last one with a line feed.
String MakeTXT = "USE SRO_VT_SHARD Select * from _RefTeleLink";
Statement stm = conn.createStatement();
ResultSet rs = stm.executeQuery(MakeTXT);
List<String> rows = new ArrayList<>();
StringBuilder row = new StringBuilder();
ResultSetMetaData meta = rs.getMetaData();
final int colCount = meta.getColumnCount();
while (rs.next()) {
row.setLength(0);
for (int c=0; c<=colCount; c++)
row.append(rs.getString(c)).append("\t");
row.setCharAt(row.length()-1, '\n');
rows.add(row.toString());
}
rs.close();
stm.close();