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Fortify: fails to release a database resource

I am trying to see the vulnerability of my code with fortify. The report said that I have an issue which said "the function sometimes fails to release a database resource allocated by". Here is the code and in which line the issue pointed. I've tried to close the connection in the finally block but it not solve the issue. How to fix this?
private AnotherService anotherService;
private void create() {
Connection conn = null;
try {
conn = getCon(); // With fortify, there's an issue which said "the function sometimes fails to release a database resource allocated by", and it refers to this line
conn.setAutoCommit(false);
anotherService.myFunction(conn);
// the conn.commit() is inside anotherService, because I have to make one connection
// rest of code
} catch (Exception e) {
e.printStackTrace;
if (null != conn) {
conn.rollback();
}
} finally {
if (null != conn) {
conn.close();
}
}
}
private static Connection getCon() {
Connection connection = null;
try {
Class.forName("org.postgresql.Driver");
connection = DriverManager.getConnection(
"jdbc:postgresql://localhost:5432/dbname",
"username",
"password");
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
return connection;
}
Addition:
If I use try-with-resource (like this try (Connection conn = getCon()), to automatically close things, how I could call conn.rollback() in the catch block if any exception occured? Since the conn variable declared inside the try-with-resources.

Well, I solve my problem, the close method should call inside try-catch in the finally block, as mentioned in this link.
In case the link broken, here is the code that I use to solve my problem:
Statement stmt = null;
ResultSet rs = null;
Connection conn = getConnection();
try {
stmt = conn.createStatement();
rs = stmt.executeQuery(sqlQuery);
processResults(rs);
} catch (SQLException e) {
// Forward to handler
} finally {
try {
if (rs != null) {rs.close();}
} catch (SQLException e) {
// Forward to handler
} finally {
try {
if (stmt != null) {stmt.close();}
} catch (SQLException e) {
// Forward to handler
} finally {
try {
if (conn != null) {conn.close();}
} catch (SQLException e) {
// Forward to handler
}
}
}
}

"Operation not allowed after ResultSet closed" with Datasource and crawler4j

After reading through a lot of similar questions I have not been able to get a solution that works for me.
I have this methods:
In a crawler4j Controller I do this:
ArrayList<String> urls = Urls.getURLs(100);
for (String s : urls) {
System.out.println("Adding URL: " + s);
controller.addSeed(s);
}
this is getURLs():
public static ArrayList<String> getURLs(int number) {
ArrayList<String> list = new ArrayList<String>();
String getStatement = "select * from " + Configurations.getStringProperty("mysql.urls.db_name", "urls") + " where retrieved=0 limit "
+ Configurations.getStringProperty("mysql.urls.limit", "100") + ";";
ResultSet rs;
rs = Databaseclient.executeStatement(getStatement);
try {
while (rs.next()) {
list.add(rs.getString("url"));
// Databaseclient.executeStatement("update urls set retrieved = true where id = "
// + rs.getInt("id") + ";");
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
try {
rs.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return list;
}
This is my executeStatement():
public static ResultSet executeStatement(String s) {
Connection connection = null;
Statement statement = null;
ResultSet resultSet = null;
try {
// fetch a connection
connection = DataSource.getInstance().getConnection();
if (connection != null) {
statement = connection.createStatement();
resultSet = statement.executeQuery(s);
}
} catch (SQLException e) {
System.out.println("A SQLException occured executing the Statement");
e.printStackTrace();
} catch (IOException e) {
System.out.println("A IOException occured executing the Statement");
e.printStackTrace();
} catch (PropertyVetoException e) {
System.out.println("A PropertyVetoException occured executing the Statement");
e.printStackTrace();
} finally {
if (resultSet != null) {
try {
resultSet.close();
} catch (SQLException e) {
System.out.println("A SQLException occured executing the Statement");
e.printStackTrace();
}
}
if (statement != null) {
try {
statement.close();
} catch (SQLException e) {
System.out.println("A SQLException occured executing the Statement");
e.printStackTrace();
}
}
if (connection != null) {
try {
connection.close();
} catch (SQLException e) {
System.out.println("A SQLException occured executing the Statement");
e.printStackTrace();
}
}
}
return resultSet;
}
I get the error
java.sql.SQLException: Operation not allowed after ResultSet closed
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1094)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:997)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:983)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:928)
at com.mysql.jdbc.ResultSetImpl.checkClosed(ResultSetImpl.java:799)
at com.mysql.jdbc.ResultSetImpl.next(ResultSetImpl.java:6982)
at database.Urls.getURLs(Urls.java:27)
at crawler.Controller.main(Controller.java:53)
Which is the line
while (rs.next()) {
in my getURLs() method.
What am I doing wrong? There is no code between getting the statement and the while loop that could close the statement.

Your code is a bit off, but if I understand you then don't close your ResultSet in the finally block of your executeStatement method.
public static ResultSet executeStatement(Connection connection,
Statement statement, String s) {
ResultSet resultSet = null;
try {
if (statement != null) {
resultSet = statement.executeQuery(s);
}
} catch (SQLException e) {
System.out.println("A SQLException occured executing the Statement");
e.printStackTrace();
} catch (IOException e) {
System.out.println("A IOException occured executing the Statement");
e.printStackTrace();
} catch (PropertyVetoException e) {
System.out.println("A PropertyVetoException occured executing the Statement");
e.printStackTrace();
}
return resultSet;
}
Then you need to pass in a Connection and Statement, and you'll get a ResultSet back. Also, the caller should then close all three when it's done with the ResultSet.

Avoid automatic jdbc connection close in servlet

I have a servlet deployed on a Jetty 9 server that connects to a MySQL 5.6.17 server using the Connector/J JDBC driver from http://dev.mysql.com/downloads/connector/j/5.0.html.
This particular servlet fires a SQL statement inside a for loop that iterates around 10 times. I have to include the
DriverManager.getConnection(DB_URL, USER, PASSWORD);
line within this loop because the connection closes automatically after the SQL statement has been executed in every iteration of the loop.
Is there a way to keep the connection open, so that getConnection() need be executed only once before the loop starts and then i can manually close it in the finally block.
I have found many posts on this particular issue, but all refer to the connection pooling concept as the solution. But i am just interested in avoiding the connection being closed automatically after each query execution. Shouldn't this be a simple parameter? I am not facing any particular performance problem right now, but it just seems to be a waste of processor and network cycles.
Servlet Code :
public class CheckPhoneNumberRegistrationServlet extends HttpServlet {
#Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException {
System.err.println("started CheckPhoneNumberRegistrationServlet");
// define database connection details
final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
final String DB_URL = DatabaseParameters.SlappDbURL;
final String USER = DatabaseParameters.DbServer_Username;
final String PASSWORD = DatabaseParameters.DbServer_Password;
PreparedStatement prpd_stmt = null;
Connection conn = null;
ResultSet rs = null;
int resultValue;
// open a connection
/*try {
conn = DriverManager.getConnection(DB_URL, USER, PASSWORD);
} catch (SQLException e2) {
// TODO Auto-generated catch block
e2.printStackTrace();
}*/
JsonParser jsparser;
JsonElement jselement;
JsonArray jsrequestarray;
JsonArray jsresponsearray = new JsonArray();
StringBuffer jb = new StringBuffer();
String line = null;
try {
BufferedReader reader = req.getReader();
while ((line = reader.readLine()) != null)
jb.append(line);
} catch (Exception e) {
e.printStackTrace();
}
try {
jsparser = new JsonParser();
jselement = (JsonElement) jsparser.parse(jb.toString());
jsrequestarray = jselement.getAsJsonArray();
for (int i = 0; i < jsrequestarray.size(); i++) {
// System.err.println("i : " + i +
// jsrequestarray.get(i).toString());
try {
conn = DriverManager.getConnection(DB_URL, USER, PASSWORD);
prpd_stmt = conn
.prepareStatement("select slappdb.isPhoneNumberRegistered(?)");
prpd_stmt.setString(1, jsrequestarray.get(i).toString()
.replace("\"", ""));
rs = prpd_stmt.executeQuery();
if (rs.first()) {
//System.err.println("result sert from sql server : " + rs.getString(1));
//slappdb.isPhoneNumberRegistered() actually returns Boolean
//But converting the result value to int here as there is no appropriate into to Boolean conversion function available.
resultValue = Integer.parseInt(rs.getString(1));
if(resultValue == 1)
jsresponsearray.add(jsparser.parse("Y"));
else if(resultValue == 0)
jsresponsearray.add(jsparser.parse("N"));
else throw new SQLException("The value returned from the MySQL Server for slappdb.isPhoneNumberRegistered(" + jsrequestarray.get(i).toString().replace("\"", "") + ") was unexpected : " + rs.getString(1) + ".\n");
// System.err.println("y");
}
else throw new SQLException("Unexpected empty result set returned from the MySQL Server for slappdb.isPhoneNumberRegistered(" + jsrequestarray.get(i).toString().replace("\"", "") + ").\n");
} catch (SQLException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (prpd_stmt != null)
prpd_stmt.close();
} catch (SQLException e1) {
}
try {
if (conn != null)
conn.close();
} catch (SQLException e1) {
}
}
}
resp.setStatus(HttpServletResponse.SC_OK);
resp.setContentType("text/plain");
// resp.setContentLength(1024);
resp.getWriter().write(jsresponsearray.toString());
System.err.println(jsresponsearray.toString());
} catch (Exception e) {
// crash and burn
System.err.println(e);
}

The problem is that you're closing the connection inside the for loop. Just move both statements: connection opening and connection close, outside the loop.
conn = DriverManager.getConnection(DB_URL, USER, PASSWORD);
for (int i = 0; i < jsrequestarray.size(); i++) {
try {
//current code...
} catch (SQLException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (prpd_stmt != null)
prpd_stmt.close();
} catch (SQLException e1) {
}
}
}
try {
if (conn != null)
conn.close();
} catch (SQLException e1) {
}

using combobox selectedItem on a function

i have an function connexion to a database
and i have a code that i have a select and display elements in a combobox
so i want pass on class connexion.java the combobox selectedItem becaue it contains the all of databases that i have
so i want tha classe connexion be dynamic so pass the element selected on this class
i don"t know how can i do that please help me
public class Connexion {
private static Connection conn;
{
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException ex) {
Logger.getLogger(Connexion.class.getName()).log(Level.SEVERE, null, ex);}
try {
conn = DriverManager.getConnection("jdbc:mysql://localhost/mohammedia", "root", "123456");
} catch (SQLException ex) {
Logger.getLogger(Connexion.class.getName()).log(Level.SEVERE, null, ex); }
}
public static Connection getconx()
{
return conn;
}
}

Use this class
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import javax.naming.NamingException;
import org.apache.commons.dbcp.BasicDataSource;
import sun.jdbc.rowset.CachedRowSet;
public class SQLConnection {
private static Connection con = null;
private static BasicDataSource dataSource;
//we can enable and disable connection pool here
//true means connection pool enabled,false means disabled
private static boolean useConnectionPool = true;
private static int count=0;
private SQLConnection() {
/*
Properties properties = new Properties();
properties.load(new FileInputStream(""));
maxActive = properties.get("maxActive");
*/
}
public static String url = "jdbc:mysql://localhost:3306/schemaname";
public static String password = "moibesoft";
public static String userName = "root";
public static String driverClass = "com.mysql.jdbc.Driver";
public static int maxActive = 20;
public static int maxIdle = 10;
private static final String DB_URL = "driver.classs.name";
private static final String DB_USERNAME = "database.username";
static {
/*Properties properties = new Properties();
try {
properties.load(new FileInputStream("D:\\CollegeBell\\properties\\DatabaseConnection.properties"));
//properties.load(new FileInputStream("E:\\vali\\CollegeBell\\WebContent\\WEB-INF"));
//properties.load(new FileInputStream("D:\\DatabaseConnection.properties"));
url = properties.getProperty(DB_URL);
System.out.println(url);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}*/
dataSource = new BasicDataSource();
dataSource.setDriverClassName(driverClass);
dataSource.setUsername(userName);
dataSource.setPassword(password);
dataSource.setUrl(url);
dataSource.setMaxActive(maxActive);
dataSource.setMinIdle(maxIdle);
dataSource.setMaxIdle(maxIdle);
}
//public static Connection getConnection(String opendFrom) throws SQLException,
public static Connection getConnection(String openedFrom) {
count++;
System.out.println("nos of connection opened till now="+count);
System.out.println("Connection opended from "+openedFrom);
// System.out.println("Connection Opended ");
try {
if (useConnectionPool) {
con = dataSource.getConnection();
System.out.println(dataSource.getMinEvictableIdleTimeMillis());
//dataSource.setMaxWait(15000);
System.out.println(dataSource.getMaxWait());
System.out.println(count );
} else {
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection(url, userName, password);
}
}
//System.out.println("Connection : " + con.toString());
catch (SQLException e) {
e.printStackTrace();
}
catch (Exception e) {
e.printStackTrace();
}
return con;
}
public static void closeConnection(Connection con, String closedFrom)
{
//System.out.println("Connection closed from: " + con.toString());
// System.out.println("Connection closed from: " + closedFrom);
//log.info("Connection closed from: " + closedFrom);
if(con != null){
count--;
System.out.println("Connection count value after closing="+count);
System.out.println("Connection closed from: " + closedFrom);
try {
con.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
//added by nehal
public static void closeStatement(Statement ps, String closedFrom)
{
if(ps != null){
System.out.println("Statement closed from: " + closedFrom);
try {
ps.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
public static void closePreparedStatement(PreparedStatement ps, String closedFrom)
{
if(ps != null){
System.out.println("Statement closed from: " + closedFrom);
try {
ps.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
public static void closeResultSet(ResultSet rs, String closedFrom)
{
if(rs != null){
System.out.println("ResultSet closed from: " + closedFrom);
try {
rs.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
//added by nehal
/*public static ResultSet executeQuery(String query) throws Exception {
Connection con = null;
Statement stmt = null;
ResultSet rs = null;
CachedRowSet crset = null;
try {
con = getConnection();
stmt = con.createStatement();
rs = stmt.executeQuery(query);
crset = new CachedRowSet();
crset.populate(rs);
} catch (Exception e) {
throw e;
} finally {
if (rs != null) {
rs.close();
}
if (stmt != null) {
stmt.close();
}
if (con != null && !con.isClosed()) {
con.close();
}
}
return crset;
}
public static int executeUpdate(String query) throws Exception {
Connection con = null;
Statement stmt = null;
ResultSet rs = null;
int rows = -1;
try {
con = getConnection();
stmt = con.createStatement();
rows = stmt.executeUpdate(query);
} catch (Exception e) {
throw e;
} finally {
if (rs != null) {
rs.close();
}
if (stmt != null) {
stmt.close();
}
if (con != null && !con.isClosed()) {
con.close();
}
}
return rows;
}
public static boolean execute(String query) throws Exception {
Connection con = null;
Statement stmt = null;
ResultSet rs = null;
boolean rowsreturned = false;
try {
con = getConnection();
stmt = con.createStatement();
rowsreturned = stmt.execute(query);
} catch (Exception e) {
throw e;
} finally {
if (rs != null) {
rs.close();
}
if (stmt != null) {
stmt.close();
}
if (con != null && !con.isClosed()) {
con.close();
}
}
return rowsreturned;
}*/
/*
* public static void closeConnection(Connection con) { try { con.close();
* con=null; } catch (SQLException e) { // TODO Auto-generated catch block
* e.printStackTrace(); } }
*/
}

A JComboBox accepts any kind of object, so you can simply do something like this.
Connection con = new Connection();
JComboBox box = getBox();
box.addItem(con);
And to retreive the value:
JComboBox box = getBox();
Connection con = (Connection)box.getSelectedItem();
However in your Connection class you must override the toString() function, because this is used to display the box.
class Connection
{
public String toString()
{
return "BoxItemDisplayvalue"; <--- here you must put something meaningfull which is displayed in the box.
}
}
So you can instantiate a connection representing the connection that you want, and when the user selects an item from the combobox, you will have the connection it represents.

For what i understand, you have 2 classes..
One the gui where you have a comboBox with the schema name where u want to get connected.
So you have to have a EventListener to "listen" when the submit button is pressed.
For example:
Connection con = null;
JButton submitButton = new JButton("Confirm db");
submitButton.addActionListener(new MyConnectionListener());
..
//Could be inner class
class MyConnectionListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent evt){
if(cmb.getSelectedItem() != null){
con = Connection.getConx(cmb.getSelectedItem().toString());
}
}
}
And in your Connexion class
public class Connexion {
public static Connection getconx(String schema)
{
Connection conn = null;
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException ex) {
Logger.getLogger(Connexion.class.getName()).log(Level.SEVERE, null, ex);}
try {
conn = DriverManager.getConnection("jdbc:mysql://localhost/"+schema, "root", "123456");
} catch (SQLException ex) {
Logger.getLogger(Connexion.class.getName()).log(Level.SEVERE, null, ex); }
}
return conn;
}
}

can't get connection to database through java class

i'm trying to establish connection with mysql database through file properties and then run the information from servlet. my Connection class looks like this:
public class pageDao {
private Connection connection;
private Statement statement;
private pageDao() {
Properties prop = new Properties();
try {
//Class.forName("oracle.jdbc.driver.OracleDriver");
//Class.forName("org.gjt.mm.mysql.Driver");
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException cnfe) {
System.out.println("Error loading driver: " +cnfe);
}
try {
try {
//load a properties file
prop.load(new FileInputStream("config.properties"));
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
String db = prop.getProperty("database");
String dbuser = prop.getProperty("dbuser");
String dbpassword = prop.getProperty("dbpassword");
connection = DriverManager.getConnection(db,dbuser,dbpassword);
} catch (SQLException e) {
e.printStackTrace();
}
}
private static pageDao thisDao;
public static pageDao gedDao()
{
if(thisDao == null)
thisDao = new pageDao();
return thisDao;
}
public PageData getPage(String id)
{
PageData data = new PageData();
try {
statement = connection.createStatement();
ResultSet rs = statement.executeQuery("select * from pages where id='"+id+"'");
if(rs.next())
{
data.setId(rs.getString("id"));
data.setParentid(rs.getString("parentid"));
data.setTitle(rs.getString("title"));
data.setTitle4menu(rs.getString("title4menu"));
data.setKeywords(rs.getString("keywords"));
data.setDescription(rs.getString("description"));
data.setMaintext(rs.getString("maintext"));
}
else
return null;
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return data;
}
when i run it, it doesn't show the mistake that connection wasn't established, but when it gets to the
public PageData getPage(String id) {
PageData data = new PageData();
try {
statement = connection.createStatement();
it throws java.lang.NullPointerException.
can anybody help me out with that?

there is no issue with code.
check your passing parameter ...
check sample
private Connection getConnection() {
try {
String dbUrl = "jdbc:mysql://localhost:3306/projectmining";
Class.forName("com.mysql.jdbc.Driver");
return DriverManager.getConnection(dbUrl, "root", "admin");
} catch (Exception ex) {
ex.printStackTrace();
}
return null;
}