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How to save the results of a query on variables for each field on Java?

I need to accomplish the following:
1.- Save on different variables each field of a query result (Oracle DB).
The query result could be 1 o more rows (5 average).
2.- Invoke a WebService for each row.
4.- Wait for the WebService answer and then repeat the process.
I think that saving the result of 1 row and then invoke the WebService it easy but the problem is when the query result throws more than 1 row.
How can I do this? Is Arraylist the answer?
EDIT: I am using the following code. How can I print the arraylist to see if the connection is working?
If I run this i get:
com.packagename.SomeBean#1d251891
com.packagename.SomeBean#48140564
com.packagename.SomeBean#58ceff1
Connection con = null;
Statement stmt = null;
ResultSet rs = null;
List<SomeBean> v = new ArrayList<SomeBean>();
String query = "select * from table where ROWNUM BETWEEN 1 and 3";
try
{
Class.forName("oracle.jdbc.driver.OracleDriver");
con = DriverManager.getConnection("jdbc:oracle:thin:user/pass#localhost:port:SID");
stmt = con.createStatement();
rs = stmt.executeQuery(query);
while( rs.next() ){
SomeBean n = new SomeBean();
n.setColumn1(rs.getInt("column1"));
n.setColumn2(rs.getString("column2"));
n.setColumn3(rs.getString("column3"));
n.setColumn4(rs.getInt("column4"));
n.setColumn5(rs.getString("column5"));
n.setColumn6(rs.getString("column6"));
n.setColumn7(rs.getString("column7"));
...
v.add(n);
}
for(SomeBean s : v){
System.out.println(s);
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
} finally {
try {
stmt.close();
con.close();
} catch (SQLException e) {
e.printStackTrace();
}
}

Answering to your question is quite difficoult.
But I can give you some hints.
Your startpoint is JDBC.
The Java Database Connectivity (JDBC)
The Java Database Connectivity (JDBC) API is the industry standard for database-independent connectivity between the Java programming language and a wide range of databases SQL databases and other tabular data sources, such as spreadsheets or flat files. The JDBC API provides a call-level API for SQL-based database access.
The Java Database Connectivity (JDBC)
Once you are able to establish a connection to the DB, this snippet can help you answering to your question.
// start connection
List<SomeBean> v = new ArrayList<SomeBean>();
Statement st;
try
{
st = conn.createStatement();
ResultSet rs = st.executeQuery(sql);
while( rs.next() ){
SomeBean n = new SomeBean();
n.setFirstField(rs.getInt("firstfield"));
n.setSecondField(rs.getString("secondfield"));
...
...
v.add(n);
}
}
catch (SQLException e)
{
e.printStackTrace();
}
// close connection
Once you have your collection of beans, just write a for loop that calls the webservice one time for each bean.
for(SomeBean s : v){
callToYouWS(s);
}

JDBC Sqlite rs.next - don't go in rs.next-loop when PreparedStatement has a variable

It is really freaking me out. In my code I hand over a generated uuid as my private Key. Now I want to select from a table with only one value inside (avg_distance_as). Everything works fine when I write the statement with a fix uuid. But because I want to get the specific row with my current uuid, I want to put that in my statement too.
soooo no error nothing - he does not even call the syso in the rs.next loop. This one is working:
public int getavgDistanceAs(String uuid) {
try {
Class.forName("org.sqlite.JDBC");
con = DriverManager.getConnection("jdbc:sqlite:test.db");
statement = con.prepareStatement("Select avg_distance_as, UUID from avg_distance");
System.out.println(uuid);
statement.setString(1, uuid);
ResultSet rs = statement.executeQuery();
while (rs.next()) {
System.out.println(rs.getDouble(1));
System.out.println("test");
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
statement.close();
con.close();
} catch (Exception e) {
e.printStackTrace();
}
}
return 0;
}
But this one isn't and it looks PRETTY much the same:
statement = con.prepareStatement("Select avg_distance_as, UUID from avg_distance where UUID = ?");
statement.setString(1, uuid);
Would be awesome if someone could help :)

OK - got it... I messed up my order in the calculation. #Kayaman was right: uuid was missing at the time needed.

Java prepared statement in try-with-resources not working [duplicate]

This question already has answers here:
How should I use try-with-resources with JDBC?
(5 answers)
Closed 8 years ago.
Yesterday multiple people on Stack recommended using try-with-resources. I am doing this for all my database operations now. Today I wanted to change Statement to PreparedStatement to make the queries more secure. But when I try to use a prepared statement in try-with-resources I keep getting errors like 'identifier expected' or ';' or ')'.
What am I doing wrong? Or isnt this possible? This is my code:
try (Connection conn = DriverManager.getConnection(DBURL, DBUSER, DBPASS);
PreparedStatement stmt = conn.prepareStatement("SELECT id FROM users WHERE id = ? LIMIT 1");
stmt.setInt(1, user);
ResultSet rs = stmt.executeQuery()) {
// if no record found
if(!rs.isBeforeFirst()) {
return false;
}
// if record found
else {
return true;
}
} catch (SQLException e) {
// log error but dont do anything, maybe later
String error = "SQLException: " + e.getMessage() + "\nSQLState: " + e.getSQLState() + "\nVendorError: " + e.getErrorCode();
return false;
}

A try-with-resource statement is used to declare (Autoclosable) resources. Connection, PreparedStatement and ResultSet are Autoclosable, so that's fine.
But stmt.setInt(1, user) is NOT a resource, but a simple statement. You cannot have simple statements (that are no resource declarations) within a try-with-resource statement!
Solution: Create multiple try-with-resource statements!
try (Connection conn = DriverManager.getConnection(DBURL, DBUSER, DBPASS)) {
executeStatement(conn);
} catch (SQLException e) {
// log error but dont do anything, maybe later
String error = "SQLException: " + e.getMessage() + "\nSQLState: " + e.getSQLState() + "\nVendorError: " + e.getErrorCode();
return false;
}
private void executeStatement(Connection con) throws SQLException {
try (PreparedStatement stmt = conn.prepareStatement("SELECT id FROM users WHERE id=? LIMIT 1")) {
stmt.setInt(1, user);
try (ResultSet rs = stmt.executeQuery()) {
// process result
}
}
}
(Please note that technically it is not required to put the execution of the SQL statement into a separate method as I did. It also works if both, opening the connection and creating the PreparedStatement are within the same try-with-resource statement. I just consider it good practice to separate connection management stuff from the rest of the code).

try this code:
try (Connection conn = DriverManager.getConnection(DBURL, DBUSER, DBPASS)) {
PreparedStatement stmt = conn.prepareStatement("SELECT id FROM users WHERE id = ? LIMIT 1");
stmt.setInt(1, user);
ResultSet rs = pstmt.executeQuery())
// if no record found
if(!rs.isBeforeFirst()) {
return false;
}
// if record found
else {
return true;
}
} catch (SQLException e) {
// log error but dont do anything, maybe later
String error = "SQLException: " + e.getMessage() + "\nSQLState: " + e.getSQLState() + "\nVendorError: " + e.getErrorCode();
return false;
}
note that here, resource is your Connection and you have to use it in the try block ()

Move
stmt.setInt(1, user);
ResultSet rs = stmt.executeQuery()
...within the try{ /*HERE*/ }
This is because stmt is the resource being created try (/*HERE*/) {} to be used try{ /*HERE*/ }
Try-with-resources
try (/*Create resources in here such as conn and stmt*/)
{
//Use the resources created above such as stmt
}
The point being that everything created in the resource creation block implements AutoClosable and when the try block is exited, close() is called on them all.
In your code stmt.setInt(1, user); is not an AutoCloseable resource, hence the problem.

How to call Stored Procedure and prepared statement

In the below code I want to call one stored procedures and execute one Query. I am facing error at statement.executeUpdate(); Please help in fixing it. I am not sure where it going wrong.
public void Dbexe() {
Connection connection;
connection = DatabaseConnection.getCon();
CallableStatement stmt;
try {
stmt = connection.prepareCall("{CALL optg.Ld_SOpp}");
stmt.executeUpdate();
stmt.close();
} catch (SQLException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
System.out.println("Stored Procedure executed");
//PreparedStatement statement = null;
// ResultSet rs = null;
try{
PreparedStatement statement;
try {
statement = connection.prepareStatement("MERGE INTO OPTG.R_VAL AS TARGET USING" +
........... +
"");
statement.executeUpdate(); //Here the exception is thrown
statement.close();
connection.commit();
connection.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// statement = connection.prepareStatement(query);
//statement.close();
}
finally{
System.out.println("Data is copied to the Table");
}
}

Little off-topic: You should use CallableStatement instead if you want to call a store procedure (see documentation):
CallableStatement callableStatement = connection.prepareCall("{call opptymgmt.Load_SiebelOpportunity}");
ResultSet rs = callableStatement.executeQuery();
I would also suggest you check this topic How to properly clean up JDBC resources in Java?. It was very helpful to me.
Update: based on this stack trace:
com.ibm.db2.jcc.am.mo: DB2 SQL Error: SQLCODE=-104, SQLSTATE=42601, SQLERRMC=MERGE INTO OPPTYMGMT.REVENUE_VALIDAT;BEGIN-OF-STATEMENT;<variable_set>, DRIVER=4.7.85
The problem seems to be in the sql sentence you're trying to execute. I mean, is an error from DB2, not java. You should check your sql statement.

I got it working in this method:
PreparedStatement myStmt = conn.prepareStatement(sqlQuery);
myStmt.setInt(1, id); //position of parameter (1,2,3....) , value
ResultSet rs = myStmt.executeQuery();
while (rs.next()) {
int jobId = rs.getInt("jobId"); ....... }

Operation not allowed after ResultSet closed

Allright been trying to figure this out the last 2 days.
Statement statement = con.createStatement();
String query = "SELECT * FROM sell";
ResultSet rs = query(query);
while (rs.next()){//<--- I get there operation error here
This is the query method.
public static ResultSet query(String s) throws SQLException {
try {
if (s.toLowerCase().startsWith("select")) {
if(stm == null) {
createConnection();
}
ResultSet rs = stm.executeQuery(s);
return rs;
} else {
if(stm == null) {
createConnection();
}
stm.executeUpdate(s);
}
return null;
} catch (Exception e) {
e.printStackTrace();
con = null;
stm = null;
}
return null;
}
How can I fix this error?

It's hard to be sure just from the code you've posted, but I suspect that the ResultSet is inadvertently getting closed (or stm is getting reused) inside the body of the while loop. This would trigger the exception at the start of the following iteration.
Additionally, you need to make sure there are no other threads in your application that could potentially be using the same DB connection or stm object.

IMHO, you should do everything you need with your ResultSet before you close your connection.

there are few things you need to fix. Opening a connection, running a query to get the rs, closing it, and closing the connection all should be done in the same function scope as far as possible. from your code, you seem to use the "con" variable as a global variable, which could potentially cause a problem. you are not closing the stm object. or the rs object. this code does not run for too long, even if it has no errors. Your code should be like this:
if (stringUtils.isBlank(sql)){
throw new IllegalArgumentsException ("SQL statement is required");
}
Connection con = null;
PreparedStatement ps =null;
Resultset rs = null;
try{
con = getConnection();
ps = con.preparestatement(sql);
rs = ps.executeQuery();
processResults(rs);
close(rs);
close(ps);
close(con);
}catch (Execption e){
log.Exception ("Error in: {}", sql, e);
throw new RuntimeException (e);
}finally{
close(rs);
close(ps);
close(con);
}

use another Statement object in inner loop
Like
Statement st,st1;
st=con.createStatement();
st1=con.createStatement();
//in Inner loop
while(<<your code>>)
{
st1.executeQuery(<<your query>>);
}

I know this is a few years late, but I've found that synchronizing the db methods usually get rid of this problem.