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Why different issues are found when using different versions of SonarQube?

I'm testing sonar in order to ensure the closing database connections and I'm having extrange results I don't understand.
I'm trying two versions of the code executing the maven goal "sonar:sonar" from eclipse with the embeded maven version 3.3.9.
I've tried with three versions of sonarqube server: 5.6.6, 6.2 and 6.4.
With this code
package db;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import javax.naming.InitialContext;
import javax.sql.DataSource;
public class TestClosingResources {
public static void main(String[] args) {
Connection con = null;
ResultSet rsGet = null;
PreparedStatement psGet = null;
try {
DriverManager.registerDriver (new com.mysql.jdbc.Driver());
con = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "test", "test");
psGet = con.prepareStatement("SELECT * FROM TEST");
rsGet = psGet.executeQuery();
int counter = 0;
while (rsGet.next()) {
counter++;
System.err.println(counter);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (rsGet != null) {
rsGet.close();
}
} catch (Exception e2) {
e2.printStackTrace();
}
rsGet = null;
try {
if (psGet != null) {
psGet.close();
}
} catch (Exception e2) {
e2.printStackTrace();
}
psGet = null;
}
}
}
I have these issues about closing resources:
sonarqube 5.6.6:
Close this "Connection"
Close this "PreparedStatement"
sonarqube 6.2:
Close this "Connection"
Close this "PreparedStatement"
sonarqube 6.4:
Close this "Connection"
My question with this code is:
Why does 5.6.6 and 6.2 complain about PreparedStatement when it's
closed exactly the same than the ResultSet?
And whith this code (only changes the way I retrieve the connection, it doesn't matter if it would work or not)
package db;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import javax.naming.InitialContext;
import javax.sql.DataSource;
public class TestClosingResources {
public static void main(String[] args) {
Connection con = null;
ResultSet rsGet = null;
PreparedStatement psGet = null;
try {
InitialContext ctx = new InitialContext();
DataSource ds = (DataSource)ctx.lookup("java:comp/env/jdbc/testci");
con = ds.getConnection();
psGet = con.prepareStatement("SELECT * FROM TEST");
rsGet = psGet.executeQuery();
int counter = 0;
while (rsGet.next()) {
counter++;
System.err.println(counter);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (rsGet != null) {
rsGet.close();
}
} catch (Exception e2) {
e2.printStackTrace();
}
rsGet = null;
try {
if (psGet != null) {
psGet.close();
}
} catch (Exception e2) {
e2.printStackTrace();
}
psGet = null;
}
}
}
sonarqube 5.6.6:
Close this "PreparedStatement"
sonarqube 6.2:
Close this "PreparedStatement"
sonarqube 6.4:
no issues about closing resources
My questions with this code are:
Why does 5.6.6 and 6.2 complain about PreparedStatement when it's
closed exactly the same than the ResultSet?
Why doesn't any version complain about not closing the connection?
Thanks

The reason why some issues are not detected in more recent versions is due to the fact that static analyzer doing the analysis was improved.
Plugin used for Java source code analysis is called SonarJava, and it has independent release cycle than SonarQube. You should always use the latest release to obtain best results. Use update center on your SonarQube server to update to the latest available release.

How to get a String from a field

I've got a mysql question within java. I've got a mysql database with different tables. I currently got a database called 'litebans' and a table called 'litebans_mutes'.
Within that table there is a row called reason and under that reason (let's say what's within reason) there's a string called 'This is a test' and 'sorry'; how would I get the string 'This is a test' and 'sorry' associated with the same 'uuid' row in java? Here is a picture explaining more:
Here is an image explaining the sql format
Additionally, i've currently initialized all variables and such in java, i currently have this code:
http://hastebin.com/odumaqazok.java (Main class; using it for a minecraft plugin)
The below code is the MySQL class; api used to connect and execute stuff.
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import net.octopusmc.punish.Core;
public class MySQL {
public static Connection openConnection() {
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e1) {
System.err.println(e1);
e1.printStackTrace();
}
try {
Connection conn = DriverManager.getConnection("jdbc:mysql://" + Core.host + ":" + Core.port + "/" + Core.database, Core.user, Core.pass);
System.out.println("Currently connected to the database.");
return conn;
} catch (SQLException e) {
System.out.println("An error has occured while connecting to the database");
System.err.println(e);
e.printStackTrace();
}
return null;
}
public static void Update(String qry) {
try {
Statement stmt = Core.SQLConn.createStatement();
stmt.executeUpdate(qry);
stmt.close();
} catch (Exception ex) {
openConnection();
System.err.println(ex);
}
}
public static Connection getConnection() {
return Core.SQLConn;
}
public static ResultSet Query(String qry) {
ResultSet rs = null;
try {
Statement stmt = Core.SQLConn.createStatement();
rs = stmt.executeQuery(qry);
} catch (Exception ex) {
openConnection();
System.err.println(ex);
}
return rs;
}
}
An example using that api above is shown below:
try {
ResultSet rs = MySQL.Query("QUERY GOES HERE");
while (rs.next()) {
//do stuff
}
} catch (Exception err) {
System.err.println(err);
err.printStackTrace();
}
tl;dr: I want to get the two fields called 'reason' with the give 'uuid' string field.

First , make sure that your using the jdbc mysql driver to connect to the database
Defile a class where you could write the required connection and create statement code.
For example
class ConnectorAndSQLStatement {
ResultSet rs = null;
public Statement st = null;
public Connection conn = null;
public connect() {
try {
final String driver = "com.mysql.jdbc.Driver";
final String db_url = "jdbc:mysql://localhost:3306/your_db_name";
Class.forName(driver);//Loading jdbc Driver
conn = DriverManager.getConnection(db_url, "username", "password");
st = conn.createStatement();
rs = st.executeQuery("Select what_you_want from your_table_name");
while (rs.next()) {
String whatever = rs.getInt("whatever ");
System.out.print(whatever);
}
} catch (SQLException se) {
se.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
Just call this function and the magic :D
Hope it is helpful

Establishing connection between Android app and Oracle DB using JDBC driver

I am having trouble establishing a connection between my app and an Oracle DB using JDBC drivers.
Host Oracle ver.: Oracle Database 11g Release 11.2.0.1.0 - 64bit Production
.Jar jdbc drivers I have tried: ojdbc5.jar, ojdbc6.jar, ojdbc14.jar, all from oracle itself.
I have granted the application the permission in the manifest.
<uses-permission android:name="android.permission.INTERNET" />
I get absolutely no response, nothing in the logcat. The SQL statement has no effect on the remote DB.
I can connect the remote DB with the same login credentials on my machine with SQL Plus and have all the privileges.
Code from MainActivity.java
package testapp.myapplication;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import java.sql.ResultSet;
import java.util.ArrayList;
public class MainActivity extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
try {
super.onCreate(savedInstanceState);
ConnectOra db = new ConnectOra();
ResultSet rs = db.getResult();
ArrayList<String> list = new ArrayList<String>();
while (rs.next()) {
list.add(rs.getString(1));
System.out.println(rs.getString(1));
}
} catch (Exception e) {
System.out.print(e);
}
}
public void btn(View view) {
startActivity(new Intent(MainActivity.this, MainActivity.class));//Just to refresh the mainact.
}
}
Code from ConnectOra.java:
package testapp.myapplication;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import android.util.Log;
public class ConnectOra {
private Connection conn;
private Statement stmt;
public ConnectOra() throws ClassNotFoundException {
try {
System.out.println("in try");
Class.forName("oracle.jdbc.driver.OracleDriver");
String url = "jdbc:oracle:thin:#103.A.B.C:15210/mdb";
this.conn = DriverManager.getConnection(url,"XXX","pw");
this.conn.setAutoCommit(false);
this.stmt = this.conn.createStatement();
} catch(SQLException e) {
Log.d("tag", e.getMessage());
}
}
public ResultSet getResult() throws SQLException {
ResultSet rset = stmt.executeQuery("select * from emp;");
System.out.println(rset+"");
stmt.close();
return rset;
}
}
The selected answer works and my code works too.
Android cant work with ojdbc5.jar, ojdbc6.jar as they require some Java SE components not available on Android. So, we have to use ojdbc14.jar since its older than ojdbc5.jar and ojdbc6.jar and doesn't require advance Java components, this also means that only the basic functions are there with ojdbc14.jar.
With ojdbc14.jar you might have to set "SQLNET.ALLOWED_LOGON_VERSION=8" in sqlnet.ora on the remote host running the DB. This will allow older clients to connect to newer DB otherwise it throws the error ORA-28040: No matching authentication protocol.
It is also vital to close the Connection and Statement after the SQL statements have been executed, else the changes aren't saved in the actual remote DB.

Can you try out this code and post the error log. Also a word of caution, you really shouldnt do this, you should have an application sever like this to manage connections to Oracle DB. But if you wanna play it unsafe, try out this code :
String driver = "oracle.jdbc.driver.OracleDriver"; //
String serverName = "localhost";
String portNumber = "1521";
String db = "XE";
String url = "jdbc:oracle:thin:#" + serverName + ":" + portNumber + ":"
+ db; // connectOracle is the data
// source name
String user = "system"; // username of oracle database
String pwd = "root"; // password of oracle database
Connection con = null;
ServerSocket serverSocket = null;
Socket socket = null;
DataInputStream dataInputStream = null;
DataOutputStream dataOutputStream = null;
try {
Class.forName(driver);// for loading the jdbc driver
System.out.println("JDBC Driver loaded");
con = DriverManager.getConnection(url, user, pwd);// for
// establishing
// connection
// with database
Statement stmt = con.createStatement();
serverSocket = new ServerSocket(8888);
System.out.println("Listening :8888");
while (true) {
try {
socket = serverSocket.accept();
System.out.println("Connection Created");
dataInputStream = new DataInputStream(
socket.getInputStream());
dataOutputStream = new DataOutputStream(
socket.getOutputStream());
System.out.println("ip: " + socket.getInetAddress());
// System.out.println("message: " +
// dataInputStream.readUTF());
ResultSet res=stmt.executeQuery("select * from person");
while(res.next()){
System.out.println(res.getString(1));
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
if (dataInputStream != null) {
try {
dataInputStream.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (dataOutputStream != null) {
try {
dataOutputStream.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
And read again, this is not recommended.

Connection from CachedRowSet

I have the following Java 7 code to create a CachedRowSet.
CachedRowSet crs = RowSetProvider.newFactory().createCachedRowSet();
Is there a way to get the Connection object from the CachedRowSet object? I would like to set autoCommit to false on the Connection object before invoking the acceptChanges() on CachedRowSet as I'm getting the following exception when invoking acceptChanges().
javax.sql.rowset.spi.SyncProviderException: Can't call commit when autocommit=true
There is a COMMIT_ON_ACCEPT_CHANGES field on CachedRowSet, but it's Deprecated.

Well, it took some time for me to reproduce the issue at my end. Setting the autoCommit value of the Connection to false via conn.setAutoCommit(false); resolved this issue.
Following is the sample working program:
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import javax.sql.rowset.CachedRowSet;
import javax.sql.rowset.RowSetProvider;
public class CRSetChecker {
public static void main(String[] args) {
String connectString = "jdbc:oracle:thin:scott/tiger" +
"#(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)" +
"(HOST=myorahost)(PORT=5521))" +
"(CONNECT_DATA=(SID=myorasid)))";
//Get DB connection
Connection conn = (new CRSet()).getConnection(connectString);
if (conn == null) {
System.out.println("Connection failed");
System.exit(0);
} else {
System.out.println("Connection established successfully!");
try {
CachedRowSet crs =
RowSetProvider.newFactory().createCachedRowSet();
String query="select ename from emp";
crs.setCommand(query);
crs.execute(conn);
//Set auto commit false
conn.setAutoCommit(false);
int count = 0;
while(crs.next()){
String name = crs.getString(1);
count++;
System.out.println(name);
if(count==1){
crs.updateString(1, "COOPER");
crs.updateRow();
crs.acceptChanges(conn);
System.out.println("After update:"+crs.getString(1));
}
}
conn.close();
} catch (SQLException e1) {
e1.printStackTrace();
}
}
}
public Connection getConnection(String connectString)
{
Connection con = null;
try {
try {
Class.forName("oracle.jdbc.OracleDriver");
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
con = DriverManager.getConnection(connectString);
} catch (SQLException ex) {
ex.printStackTrace();
}
return con;
}
}

java - creating an oracle database connection

Does anyone know what the best way is to create a new oracle database connection. This is what I currently have:
private static getConnection() throws Exception {
if (!isDriverRegistered){
DriverManager.registerDriver(new oracle.jdbc.OracleDriver());
isDriverRegistered = true;
}
return DrvierManager.getConnection(connectionString);
}

You are not supposed to register the driver yourself; the JDBC driver itself will do that, when its class is loaded. So, do not call DriverManager.registerDriver yourself.
There are two steps: make sure the JDBC driver class is loaded, and get a connection.
To load the JDBC driver class, use a line like this:
Class.forName("oracle.jdbc.OracleDriver");
Then get the connection with a call to DriverManager.getConnection:
Connection conn = DriverManager.getConnection(connectionString);
Note that if you are using a newer JDBC version and a suitable driver, you do not even need to load the driver class explicitly; it will be found and loaded automatically (via Java's service discovery mechanism). In that case you only need to call DriverManager.getConnection.

this class may help you
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class JDBCHelper {
public static void close(Statement obj)
{
try
{
if(obj!=null)
obj.close();
}
catch(SQLException e)
{
e.printStackTrace();
}
}
public static void close(ResultSet obj)
{
try
{
if(obj!=null)
obj.close();
}
catch(SQLException e)
{
e.printStackTrace();
}
}
public static void close(Connection obj)
{
try
{
if(obj!=null)
obj.close();
}
catch(SQLException e)
{
e.printStackTrace();
}
}
public static Connection getConnection()
{
Connection con = null;
String url = "url" //give url
String pwd = "password";//give password
String uid = "userId";//give userid
try
{
Class.forName("oracle.jdbc.OracleDriver"); //pass driver name
con = DriverManager.getConnection(url,uid,pwd);
con.setAutoCommit(false);
}
catch(Exception e)
{
if(con!=null)
try {
con.rollback();
} catch (SQLException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
e.printStackTrace();
}
return con;
}
}