You need to learn how PreparedStatement actually works. I highly recommend you follow a tutorial to learn how to use it, then follow the pattern for your own code.
But it's also all in the documentation, so let be quote the various relevant pieces.
The javadoc of executeQuery() says:
Executes the SQL query in this PreparedStatement object and returns the ResultSet object generated by the query.
The code in the question is already wrong at this point, since it **ignores the return value of the executeQuery() call.
In addition, the javadoc of getResultSet() says:
Retrieves the current result as a ResultSet object. This method should be called only once per result.
The code in the question is even more wrong at this point, since it calls getResultSet() repeatedly in a loop.
If you had read the javadoc of the methods you're using, it would have been obvious that something is wrong. As already stated, going through a tutorial would have shown how to do this right. Actually, any web search for examples of executing a query using JDBC would show that.
For extra background information for how it works, the javadoc of execute() says:
Executes the SQL statement in this PreparedStatement object, which may be any kind of SQL statement. Some prepared statements return multiple results; the execute method handles these complex statements as well as the simpler form of statements handled by the methods executeQuery and executeUpdate.
The execute method returns a boolean to indicate the form of the first result. You must call either the method getResultSet or getUpdateCount to retrieve the result; you must call getMoreResults to move to any subsequent result(s).
The javadoc of getMoreResults() says:
Moves to this Statement object's next result, returns true if it is a ResultSet object, and implicitly closes any current ResultSet object(s) obtained with the method getResultSet.
The "return multiple results" is not talking about multiple rows from a single query, but about multiple results from multiple queries. It generally requires the execution of a stored procedure, or a block of SQL code, for this to happen.
This is how to correctly get the multiple rows from the execution of a single SELECT statement:
String qry = "SELECT KIDSNAME FROM TBLKIDS WHERE CID = ?";
try (PreparedStatement ps = connect.prepareStatement(qry)) {
ps.setInt(1, cid);//setting CID
try (ResultSet rs = ps.executeQuery()) {
int i = 0;
while (rs.next()) {
out[i] = rs.getString("KIDSNAME");
i++;
}
}
}
If the SQL code in question had returned multiple result sets, you would do it this way:
try (PreparedStatement ps = connect.prepareStatement(qry)) {
// call ps.setXxx() methods here
boolean isResultSet = ps.execute();
while (isResultSet) {
try (ResultSet rs = ps.getResultSet()) {
int i = 0;
while (rs.next()) {
// call rs.getXxx() methods here
i++;
}
}
isResultSet = ps.getMoreResults();
}
}
That is better written using for loops, to keep the loop logic together:
try (PreparedStatement ps = connect.prepareStatement(qry)) {
// call ps.setXxx() methods here
for (boolean isResultSet = ps.execute(); isResultSet; isResultSet = ps.getMoreResults()) {
try (ResultSet rs = ps.getResultSet()) {
for (int i = 0; rs.next(); i++) {
// call rs.getXxx() methods here
}
}
}
}
