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Why is the file Read-Only?

I have got a Microsoft Access database in the resource folder of my Java application.
When the user clicks a button, this database is copied to the temp directory of the PC. Then I make a temporary VBS file in the same directory and execute it.
(This VBS file calls a VBA macro within the database, that deletes some records.)
However, as the macro attempts to delete the records an error is thrown stating that the database is read only.
Why does this happen?
Here is my code:
When the user clicks the button, some variables are set and then the following code is executed:
private void moveAccess() throws IOException {
String dbName = "sys_cl_imp.accdb";
String tempDbPath = System.getenv("TEMP").replace('\\', '/') + "/" + dbName;
InputStream in = ConscriptioLegere.class.getResourceAsStream("res/" + dbName);
File f = new File(tempDbPath);
Files.copy(in, f.toPath(), StandardCopyOption.REPLACE_EXISTING);
this.dbFilePath = tempDbPath;
System.out.println("access in temp");
f = null;
}
Then a connection is made to the database to update some data;
with
Connection con = DriverManager.getConnection("jdbc:ucanaccess://" + dbFilePath);
Statement sql = con.createStatement();
...
sql.close();
con.close();
Afterwards this is executed:
public boolean startImport() {
File vbsFile = new File(vbsFilePath);
PrintWriter pw;
try {
updateAccess();
} catch (IOException e) {
e.printStackTrace();
return false;
}
try{
pw = new PrintWriter(vbsFile);
pw.println("Set accessApp = CreateObject(\"Access.Application\")");
pw.println("accessApp.OpenCurrentDatabase (\"" + dbFilePath + "\")");
pw.println("accessApp.Run \"sys_cl_imp.importData\", \"" + saveLoc + "\"");
pw.println("accessApp.CloseCurrentDatabase");
pw.close();
Process p = Runtime.getRuntime().exec("cscript /nologo \"" + vbsFilePath + "\"");
While the process is running, the error occurres.
I don't understand why the database is open as ReadOnly.
I tried setting f to null after the copying of the db, but it proved not to work that way.

Based on this dicussion.
The solution is adding ;singleconnection=true to JDBC url. UCanAccess will close the file after JDBC connection closed.
Connection con = DriverManager.getConnection("jdbc:ucanaccess://" + dbFilePath +";singleconnection=true");

Thank you for your solution beckyang.
I managed to get it working with it, but there was a second mistake:
I deleted the contents of a table with java then closed the connection and run the vba procedure.
In the VBA I was attempting to delete the data again; but as there were none, this didn't work out.
After deleting the SQL from the VBA, the project worked :)

Loading csv file to GreenPlum failed on java

I'm trying to import a csv file to GreenPlum DB,
It's working with the following command from psql console (9.4.0, server 8.2.15)
\COPY data."TableName" FROM 'D:/Document.csv' DELIMITER ',' CSV;
But fails when I tried to it from my java code:
public boolean InsertFile(Path tempFile, FileDetails file) {
try{
Connection conn = GetConnectionString();
String cmd = "\\COPY data.\"TableName\" FROM 'D:/Document.csv' DELIMITER ',' CSV;";
Statement st = conn.createStatement();
int res = st.executeUpdate(selectCmd);
conn.close();
return true;
}
catch(Exception e){
return false;
}
}
The exception is syntax error because of the backslash (\)

COPY comes in two separate variants, COPY and \COPY: COPY is server based, \COPY is client based. If you just try COPY without the backslash, it should work.
public static void main(String[] args) throws Exception {
String url = "jdbc:postgresql://localhost:54380/gpadmin";
Properties props = new Properties();
props.setProperty("user","gpadmin");
props.setProperty("password","changeme");
Connection conn = DriverManager.getConnection(url, props);
String cmd = "COPY timeout FROM '/tmp/timeout.csv' DELIMITER ',' CSV;";
Statement st = conn.createStatement();
int res = st.executeUpdate(cmd);
System.out.println(res);
conn.close();
}
This worked perfectly for me.

byte[] to be stored in Oracle

I have a byte[] which is actually an image.
i want to store it in Oracle 11g. I created a BLOB Column in my Table. and by following i tried to insert it.
String imageStr = "xyz...."
byte[] data = imageStr.getBytes();
String sQuery = "insert into Table (LOCATION , BLOB_DATA) Values ('Lahore', data) ";
It throws exception "java.sql.SQLException: ORA-01465: invalid hex number"
I searched it and found that this type of query should be done via PreparedStaement.
so i did something following
PreparedStatement prepStmt = dbConnection.prepareStatement("insert into Table (LOCATION, BLOB_DATA) values(?,?);
prepStmt.setString(1, 'Lahore');
prepStmt.setBytes(2, bytes);
I start getting error on dbConnection.prepareStatement(String) because the DBConnection class is not Java Native class.
It's a Custom class made by Earlier Developers for Database Connection and it do not has prepareStatement(String) function in it.
So what to do now??
1. Should i create a method prepareStatement(String) in DBConnection class?
2. Should i go for first approach?

You can look at my example to store image in db
Statement s;
Connection c;
FileInputStream fis;
PreparedStatement ps;
File file;
try
{
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");//your driver
c=DriverManager.getConnection("Jdbc:Odbc:image","scott","tiger");//password and name changes according to your db
s=c.createStatement();
st.execute("Create table ImageStoring(Image_No number(5),Photo blob)");
}
catch(Exception e1)
{
e1.printStackTrace();
}
try
{
file=new File"D:/ARU/Aruphotos/4.jpg");
fis=new FileInputStream(file);
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
c=DriverManager.getConnection("Jdbc:Odbc:image","scott","tiger");
s=c.createStatement();
ps=c.prepareStatement("insert into ImageStoring values(?,?)");
ps.setInt(1,2);
ps.setBinaryStream(2,fis,(int)file.length());
System.out.println("success");
ps.execute();
ps.close();
c.close();
}
catch(Exception e)
{
e.printStackTrace();
}
}

Exception: Operating System error code 3

I am doing text file bulk upload in SQL Server. Whenever i tries to upload the files, gets Following Exception:
[Microsoft] [ODBC SQL Server Driver] [SQL Server]Could not bulk insert
because file 'C:/Form/Input_File/Form.txt' could not be opened.
Operating System error code 3(The system cannot find the path
specified).
Please find the below code:
public void uploadFiles()
{
File dir = new File(inputFilesPath);
String[] children = dir.list();
String completePathFileName = "";
System.out.println(" Inside Upload ::");
String saveFileNames = "";
PreparedStatement prepStat;
DBConnection dbConnection=new DBConnection();
Connection conHandler= dbConnection.getConnection();
if(null!=conHandler)
System.out.println(" Clear ::"+conHandler);
try
{
if (children != null)
{
for (int i = 0; i < children.length; i++)
{
String filename = children[i];
System.out.println(" children[i]::"+children[i]);
// File is validated based on some business rules.
if (isValidFile(filename) == 1)
{
String[] fileSplit = filename.split("E");
String[] extnSplit = fileSplit[1].trim().split(".TXT");
completePathFileName += (completePathFileName.equals(""))
? extnSplit[0] : "^" + extnSplit[0];
saveFileNames += (saveFileNames.equals(""))
? filename : "," + filename;
System.out.println(extnSplit[0]);
}
else
{
inValidFileNames += (inValidFileNames.equals(""))
? filename : ";\n" + filename;
}
}
if (!completePathFileName.trim().equals(""))
{
System.out.println(completePathFileName);
prepStat = conHandler.prepareStatement("Exec StartFileImport ?");
prepStat.setString(1, completePathFileName);
prepStat.execute();
saveFileNameToDatabase(saveFileNames);
}
}
}
catch (SQLException sql)
{
System.out.println(sql.getMessage());
}
}
Getting Connection Object from the below code:
public Connection getConnection()
{
System.out.println("In side DB Connection...");
try{
// get a database connection
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
System.out.println("Before Driver");
conn= DriverManager.getConnection("jdbc:odbc:form26qa","form26","form26");
System.out.println("After Driver");
if(conn != null)
{
System.out.println("Connection established...");
}//if
else
{
System.out.println("Connection failed...");
}//else
}//try
catch(Exception e)
{
System.out.println("Exception ocurred..."+e);
e.printStackTrace();
}//catch
return conn;
}
Explanation:
I am reading files from the input path and tried to get the fileName and file path and uploading file into SQL Server.
Application is able to find the input file in the specified path. while uploading i am getting the above mentioned Exception
Please check and suggest me to fix the issue.

The file needs to be accessable on the server. The file path is
relative to the server, not your PC. Also, if you are trying to use a
share or a mapped drive it will not work. You need to use the UNC
path.
UNC Name Examples
\\teela\admin$ (to reach C:\WINNT)
\\teela\admin$\system32 (to reach C:\WINNT\system32)
\\teela\temp (to reach C:\temp)

hxtt DBF driver locks its files

My web app receives archive, unpacks it to temp folder, reads data from extracted DBFs and then should kill garbage. Though it fails to kill temp folder since DBF files in it are locked. Here is a sample code:
public static void main( String a[] ) throws Exception
{
Class.forName( "com.hxtt.sql.dbf.DBFDriver" ).newInstance();
String url = "jdbc:DBF:/C:/TEMP/";
Properties properties = new Properties();
properties.setProperty( "charSet", "cp866" );
Connection con = null;
Statement st = null;
java.sql.Driver d = null;
con = DriverManager.getConnection( url, properties );
d = DriverManager.getDriver( url );
st = con.createStatement();
ResultSet rs = st.executeQuery( "SELECT * FROM 6QQQ201010" );
rs.close();
st.close();
con.close();
}
I put breakpoint past last line and 6QQQ201010.DBF is still locked. Any ideas? Or just a bug in the driver?

Add properties.setProperty( "delayedClose", "0" ); and driver would close handles imediately.