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Java can't read one of data ResultSet for if statement, getter returns "0"

I have "users" and "reports" tables. There are 3 types of users, with "position_no" 0 (admin), 1 (manager), 2 (clerk).
Relations are correctly set.
I want to
show reports with position_no 1 and 2 to admin.
show reports with position_no 1 and 2 to manager.
show reports with position_no 2 to clerk.
I already wrote codes for this. My problem is I couldn't detect which user is signed in. rs.getString("position_no"); gives error: "unreported exception SQLException", if I do try-catch, still same.
If I manually define new1 as 0, 1 or 2, it works correctly, but doesn't solve my problem. For example I defined for 0, if signed in user is 3, he will see as 0. I don't want this.
jframe window of the "see reports":
phpmyadmin table for users:
phpmyadmin table for reports:
As alternative method, I added getter and setter to login_form.java then set to current user.
If I print getter in same file (loginform), it shows correct user position_no. If I set as 2 and print getter on other file like clerk.java, it prints "0" instead of 2. Why?
public void fillReportJTable(JTable table){
loginf.setUserTip(0);
//System.out.println("Loginf value: " + loginf.getUserTip()); //getter shows 0 for all users
//int new1 = loginf.getUserTip(); //temporary non-working solution with getter setter
PreparedStatement st;
ResultSet rs = null;
String selectQuery = "SELECT * FROM `users` WHERE `position_no` = ?";
//String selectQuery = "SELECT * FROM `reports`";
//if(rs.next()){ //it gives error. works without it.
//this gets position no from db then goes to if statement
String tip = rs.getString("position_no");
//System.out.println("new1 degeri: " + new1);
int new1 = Integer.parseInt(tip);
if(new1==0){
selectQuery = "SELECT * FROM `reports`";
}
if(new1==1){
selectQuery = "SELECT * FROM `reports` WHERE `position_no` = 1";
}
if(new1==2){
selectQuery = "SELECT * FROM `reports` WHERE `position_no` = 2";
}
//}
try {
st= mcas.getConnection().prepareStatement(selectQuery);
rs= st.executeQuery();
DefaultTableModel tableModel = (DefaultTableModel)table.getModel();
Object[] row;
while(rs.next()){
row = new Object[5];
row[0] = rs.getInt(1); // productid
row[1] = rs.getString(2); //product name
row[2] = rs.getString(3); //report topic
row[3] = rs.getString(4); //report text
row[4] = rs.getString(5); //position_no
tableModel.addRow(row);
}
} catch (SQLException ex) {
Logger.getLogger(CLIENT.class.getName()).log(Level.SEVERE, null, ex);
}
}
here is some code from login_form.java:
String tip = rs.getString("position_no");
System.out.println(tip);
int new1 = Integer.parseInt(tip);
Login_Form loginf = new Login_Form(); //welcome yazisi icin
//int girisdegeri = new1;
loginf.setUserTip(new1); //reports icin user tip
System.out.println("Loginf degeri: " + loginf.getUserTip());
login_form top:
public class Login_Form extends javax.swing.JFrame {
private String publicusername; //username get set almak icin lazim
private int publicusertip; //user tipi alma see reports icin
Getter and setters in login_form:
public int getUserTip() {
return publicusertip;
}
public void setUserTip(int newName) { // Usertip Setter
this.publicusertip = newName;
}

It looks like you're defining a prepared statement with a parameter, but not actually setting that parameter. If you don't need to use the parameter then just use this as your first sql statement.
SELECT * FROM `users`
I'm also assuming there's some paraphrasing going on here, because it doesn't look like you're actually getting a result set from your current or commented code. So maybe check that you're actually executing the statement, with or without a parameter.

Why does my for loop in android studio stop after the first iteration?

I created a system in which I can run all my postgre sql queries with only one single Async Task Class in Android Studio. This was really(!!) challenging due to the big amount of limitations that I had to face. But this works actually really great!
//Used for connecting to database and executing queries.
//Index 0 of input string must be the query, Index 1 must be the tablename we demand
//We can only gather data from 1 table for each query, so if you need data from several tablecolumns, use multiple queries like:
//[0] = query, [1] = tablename, [2] = 2nd query, [3] = 2nd tablename, [4] = 3rd query, [5] = 3rd table name ... and so on (each query must come with a tablename)
public class DBHandler extends AsyncTask<String, Void, List<String>>
{
public AsyncResponse delegate;
#Override
protected List<String> doInBackground(String...query)
{
List<String> result = new ArrayList<String>();
String sql;
String tableresult = null;
Connection conn = null;
Statement st = null;
ResultSet rs = null;
try {
Class.forName("org.postgresql.Driver");
conn = DriverManager.getConnection("jdbc:postgresql://192.168.200.300:5439/dbname?user=anonymous&password=secretpw");
st = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE); //necessary if you want to use rs.first() after rs.next(), it makes the resultset scrollable
for (int i = 0; i <= query.length-1; i = i+2) //queries are always stored in i=0 and/or in i+2, because i+1 contain the demanded tablenames for resultset handling
{
System.out.println("I is: " +i);
if (!query[i].isEmpty())
{
System.out.println(query[i]);
sql = query[i];
rs = st.executeQuery(sql);
while (rs.next())
if (!query[i + 1].isEmpty() || !rs.getString(query[i + 1]).isEmpty()) //if i+1 is empty, there is no demanded tablename. Used when we dont need any return values (ie. INSERT, UPDATE)
result.add(rs.getString(query[i + 1])); //demanded tablename is always stored in i+1
//We add an empty entry if we demand multiple tablenames so we can keep them seperate
//Might be replaced with any other char, but you will have to backtrack all usages of DBHandler and fix the filters there
if(i+2 < query.length)
result.add(" ");
}
rs.first(); //reset pointer for rs.next()
}
rs.close();
st.close();
conn.close();
System.out.println("End of AsyncTask");
}
catch (SQLException ex)
{
ex.printStackTrace();
}
catch (Exception e)
{
e.printStackTrace();
}
return result;
}
//onPostExecute returns query result in a List.
//We need to use interaces delegate feature to send the result to other classes, like "Auslieferung", which is implementing the interface
#Override
protected void onPostExecute(List<String> result)
{
super.onPostExecute(result);
System.out.println("Result: " +result.toString());
if (!result.isEmpty())
delegate.processFinish(result);
}
}
There is a for-loop in this Async Task.
for (int i = 0; i <= query.length-1; i = i+2)
And now finally I can explain my issue:
I usually use SELECT queries, sometimes I use an INSERT query (which can be done by a single query), but when I parse an Update Query, my for-loop stops iterating after the first pass, so i+2 never happens. The update queries look like this:
String updatequeries[] = {UPDATE delivery SET contactperson = 'Jon Doe' WHERE officeid = 5, " ", UPDATE delivery SET contactemail = 'abd#def.gh' WHERE officeid = 5, " "};
Why does this for loop stop running right after the first run? The debugger does not show anything unusual, everything was parsed right and there are no queries missing. Updating a table does not return any results, but nothing depends on result values here. I tried to run 20 update queries in a single string var, but the for loop stops after the first iteration anyway. No issues are displayed in the debugger or in the logs. Have I overseen something or is there anything I don't know? Might this be a bug? Please help me! This issue drives me crazy.

Select multiple column values with Java ResultSet

I am trying to select values from a row in my MySQL table.
SELECT fortnite,psn,steam,twitch,xbox,youtube
FROM `social_media`
WHERE id = '16483378715464928'
When I try to convert the result into a string, the ResultSet only receives the first "fortnite" row. My question is, how do I retrieve the following columns and put them all into one string to return.
Here is my example code:
public static String getSocialMedia(String id) {
String ret = "";
int i = 1;
try {
Statement stmt = null;
ResultSet resultSet = null;
getConnection();
stmt = con.createStatement();
resultSet = stmt.executeQuery("SELECT fortnite,psn,steam,twitch,xbox,youtube FROM `social_media` WHERE id ='" + id + "'");
while(resultSet.next()) {
ret += resultSet.getString(i) + " ";
i++;
}
if(resultSet != null) {
resultSet.close();
}
if(stmt != null) {
stmt.close();
}
} catch (Exception e) {
e.printStackTrace();
}
return ret;
}

This is happening due to this.
while(resultSet.next()) {
ret += resultSet.getString(i) + " ";
i++;
}
In the above code inside while you need to fetch all the values either by name or index. next() function gives you the complete row not a single column.
You should change it to:
while(resultSet.next()) {
for(i = 1, i <=6, i++){
ret += resultSet.getString(i) + " ";
}
}

When i try to convert the result into a string, the ResultSet only
receives the first "fortnite" row. My question is, how do i retrieve
the following columns and put them all into one string to return.
Terminology is important here, because misunderstanding terminology may lead you to misinterpret documentation. In this case, the important terminology distinction is "row" vs. "column".
Your query SELECTs fortnite,psn,steam,twitch,xbox,youtube. Those six identifiers define six columns that each row in your result set will have. It looks like your particular query is selecting by the table's primary key, so you'll only ever have zero or one row, but other queries can return multiple rows.
You want to extract the values of all six columns of one row, but you iterate while(resultSet.next()), and ResultSet.next() moves the result set to the next row, if any, not the next column. Since you have only one row, the loop terminates after only one iteration.
It looks like you want something more like this:
if (resultSet.next()) {
for (i = 1; i <= 6; i++) {
ret += resultSet.getString(i) + " ";
}
}
The if (resultSet.next()) is necessary to move the result set to the first row, and to detect when there isn't any. Then you iterate over the columns of the result, whose number you know statically, based on the query.

How to call the result of a consult and put it in a Textfield? Mysql + Java

my textfield is called pruebamax
With this function I make the connection with the database
public ResultSet getmax() {
ResultSet r = null;
try {
String sql = "select count(*) as Cantidad from tbl_padre";
System.out.println(sql);
Statement st = cx.createStatement();
r = st.executeQuery(sql);
System.out.println(st.executeQuery(sql));
} catch (SQLException ex) {
Logger.getLogger(Tmrptryone.class.getName()).log(Level.SEVERE, null, ex);
}
return r;
}
his method in the event of a button, with this method I want to print in the textfield the data I receive from the database but I got an error.
public void actualizatext() {
try {
ResultSet r = mrp.getmax();
if (r.next()) {
String ID = r.getString("Cantidad");
pruebamax.setText(ID);
}
} catch (SQLException ex) {
Logger.getLogger(NewJFrame.class.getName()).log(Level.SEVERE, null, ex);
}
}

Now, I don't know what pruebamax means but the SQL statement you used:
String sql = "SELECT COUNT(*) AS Cantidad FROM tbl_padre";
is specifically used to count the total number of records currently maintained within the specified database table (tbl_padre). The value from that count will be held in the specified temporary field named: Cantidad. When you Use the SQL COUNT statement you are not going to be returned a String data type value. You will be expected to try and acquire a Integer value.
It will not acquire a value from your table ID field as what it looks like you expect.
To properly retrieve the records count from your applied SQL string then it should be used in this fashion:
int count = 0;
try {
String sql = "SELECT COUNT(*) AS rCount FROM tbl_padre";
Statement st = cx.createStatement();
ResultSet r = st.executeQuery(sql);
while (r.next()) {
count = r.getInt("rCount");
}
r.close();
st.close();
// Close your DB connection as well if desired.
// yourConnection.close();
//To apply this value to your JTextField:
pruebamax.setText(String.valueOf(count));
System.out.println("Total number of records in the tbl_padre " +
" table is: " + count);
}
catch (SQLException ex) {
ex.printStackTrace();
}
Try not to use actual table field names for temporary field names.
If you want to be more specific with your count then your SQL statement must be more specific as well. For example, let's assume that we want to count the number of records maintained in our table where a field named Age contains a value which is greater than 30 years old, our sql statement would look like this:
String sql = "SELECT COUNT(*) AS rCount FROM tbl_padre WHERE Age > 30";
You will of course have noticed the use of the SQL WHERE clause.

Combine Select and Update statement

I have tried to research this problem however I cannot find a solution.
Background: I have a small java program using sqlite as its DB. I am trying to update a row counter to keep track of how many time a code is searched, or how many times a row is displayed. (If a row is not displayed it will not be counted). My database table hase three columns {Codes, Description, ItemCount}
Here is code that I used to get a row
private void SrchCodeActionPerformed(java.awt.event.ActionEventevt) {
String sql = "SELECT * FROM emdcodes WHERE Codes like ?"; // SQL command
try {ps = conn.prepareStatement(sql);
ps.setString(1, EMDCODELOOKUP.getText() + "%");
rs = ps.executeQuery();
ResultsTable.setModel(DbUtils.resultSetToTableModel(rs));
} catch (Exception e) {
JOptionPane.showMessageDialog(null, e);
} }
I am using this sql code on a website version and it works. it is written in PHP.
$sqlcount = mysql_query("update emdcodes SET ItemCount = ItemCount +1 Where Codes like '$term%'");
My Question is where and how would I add the counter code to the java progam. The purpose of the counter is to maintain a list of the top 5 items searched for.
I thank anyone for their help.

I am not sure if this is exactly what are you looking for...
private void SrchCodeActionPerformed(java.awt.event.ActionEventevt) {
if (counter <= 5) {
String sql = "SELECT * FROM emdcodes WHERE Codes like ?"; // SQL command
try {ps = conn.prepareStatement(sql);
ps.setString(1, EMDCODELOOKUP.getText() + "%");
rs = ps.executeQuery();
if (rs.first()){
counter++;
}
ResultsTable.setModel(DbUtils.resultSetToTableModel(rs));
} catch (Exception e) {
JOptionPane.showMessageDialog(null, e);
}
}
}
first() ->
Moves the cursor to the first row in this ResultSet object.
Returns:
true if the cursor is on a valid row; false if there are no rows in the result set