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How do I separate Big chunk of code of JDBC into different classes?

I wrote a big chunk of codes that downloads CSV file from url, then i bulk inserted into sql database, then call data from SQL server and display on Java console. Finally select the column I want to keep and export as a new CSV file.
but all of those codes are in the same class right now. How can I separate them into different class like I want a class for just download file and another class just do the Bulk insert and another class to just do the Select Query.
Thanks for helping me out
below is my code in one class now
public class ProjectTest extends CreateTable {
public static void main(String[] args) throws MalformedURLException {
BufferedReader br = null;
String line = "";
String cvsSplitBy = ",";
URL url = new URL(
"https://quality.data.gov.tw/dq_download_csv.php?nid=43983&md5_url=9d38afbca8243a24b5b89d03a8070aff");
try (InputStream inputStream = url.openStream();
FileOutputStream fos = new FileOutputStream(
"C:\\Users\\ALICE\\Desktop\\Java\\Dropbox\\Java\\virus.csv");
Connection connection = DriverManager
.getConnection("jdbc:sqlserver://localhost:1433;databaseName=JDBCDB", "andy3", "andy"); // andy3
// //
// ,andy
Statement stmt = connection.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,
ResultSet.CONCUR_UPDATABLE);
FileOutputStream fos2 = new FileOutputStream(
"C:\\Users\\ALICE\\Desktop\\Java\\Dropbox\\Java\\NEWvirus.csv");
OutputStreamWriter osw = new OutputStreamWriter(fos2, "MS950");
BufferedWriter bw = new BufferedWriter(osw);
) {
byte[] buffer = new byte[1024];
int length;
while ((length = inputStream.read(buffer)) != -1) {
fos.write(buffer, 0, length);
}
fos.close();
stmt.executeUpdate("DROP TABLE Virus");
boolean rs = stmt.execute(CreateTable);
System.out.println("Database Created");
PreparedStatement pstmt = connection.prepareStatement(InsertData);
int executeUpdate = pstmt.executeUpdate();
if (executeUpdate > 0) {
System.out.println("Data Inserted");
} else {
System.out.println("Insert ERROR");
}
ResultSet rs4 = stmt.executeQuery("SELECT Count(*) FROM Virus");
int numberOfData = rs4.getInt(1);
System.out.println(numberOfData);
ResultSet rs3 = stmt.executeQuery(selectQuery);
ResultSetMetaData metaData = rs3.getMetaData();
DatabaseMetaData DmetaData = connection.getMetaData();
String[] types = { "TABLE" };
ResultSet rs5 = DmetaData.getTables(null, null, "Virus", types);
List<String> ColNameList = new ArrayList<String>();
while (rs5.next()) {
String tableName = rs5.getString("TABLE_NAME");
ResultSet columnRs = DmetaData.getColumns(null, null, tableName, null);
while (columnRs.next()) {
String columnName = columnRs.getString("COLUMN_NAME");
ColNameList.add(columnName);
}
System.out.print("|" + ColNameList.get(0) + " |");
System.out.print(ColNameList.get(1) + " |");
System.out.print(ColNameList.get(2) + "|");
System.out.print(ColNameList.get(3) + "|");
System.out.print(ColNameList.get(4) + "　|");
System.out.print(ColNameList.get(5) + "　|");
System.out.print(ColNameList.get(6) + "　 |");
System.out.print(ColNameList.get(7) + "　 |");
System.out.print(ColNameList.get(8) + "|");
System.out.print(ColNameList.get(9) + "　　　　 |");
System.out.print(ColNameList.get(10) + " |");
System.out.print(ColNameList.get(11) + "|");
System.out.print(ColNameList.get(12) + " |");
System.out.print(ColNameList.get(13) + " |");
System.out.print(ColNameList.get(14) + " |");
System.out.print(ColNameList.get(15) + "");
}
System.out.println();
while (rs3.next()) {
coList1.add(rs3.getString(1));
coList2.add(rs3.getString(2));
coList3.add(rs3.getString(3));
coList4.add(rs3.getString(4));
coList5.add(rs3.getString(5));
coList6.add(rs3.getString(6));
coList7.add(rs3.getString(7));
coList8.add(rs3.getString(8));
coList9.add(rs3.getString(9));
coList10.add(rs3.getString(10));
coList11.add(rs3.getString(11));
coList12.add(rs3.getString(12));
coList13.add(rs3.getString(13));
coList14.add(rs3.getString(14));
coList15.add(rs3.getString(15));
coList16.add(rs3.getString(16));
coList17.add(rs3.getString(17));
}
for (int p = 0; p < 20; p++) { // coList9.size(
System.out.print("|" + coList1.get(p) + "|");
String str2 = coList2.get(p);
if (str2.length() < 3) {
String blank = "　";
String repeated = new String(new char[(3 - str2.length())]).replace("\0", blank);
System.out.print(repeated + coList2.get(p) + "|");
} else {
System.out.print(coList2.get(p) + "|");
}
System.out.print("　" + coList3.get(p) + "|");
System.out.print(coList4.get(p) + "|");
System.out.print(coList5.get(p) + "|");
System.out.print(coList6.get(p) + "|");
System.out.print(coList7.get(p) + "|");
System.out.print(coList8.get(p) + "|");
String str = coList9.get(p);
if (str.length() < 5) {
String blank = "　";
String repeated = new String(new char[(5 - str.length())]).replace("\0", blank);
System.out.print(repeated + coList9.get(p) + "|");
} else {
System.out.print(coList9.get(p) + "|");
}
System.out.print(coList10.get(p) + "|");
System.out.print(coList11.get(p) + "|");
String str12 = coList12.get(p);
if (str12.length() < 5) {
String blank = " ";
String repeated = new String(new char[(6 - str12.length())]).replace("\0", blank);
System.out.print(repeated + coList12.get(p) + "|");
} else {
System.out.print(coList12.get(p) + "|");
}
String str13 = coList13.get(p);
if (str13.length() < 5) {
String blank = " ";
String repeated = new String(new char[(4 - str13.length())]).replace("\0", blank);
System.out.print(repeated + coList13.get(p) + "|");
} else {
System.out.print(coList12.get(p) + "|");
}
System.out.print(coList14.get(p) + "|");
System.out.print(coList15.get(p) + "|");
System.out.print(coList16.get(p) + "|");
System.out.print(coList17.get(p) + "|");
System.out.println();
}
rs3.beforeFirst();
StringBuilder builder = new StringBuilder();
builder.append("CaseID").append(",").append("Age").append(",").append("Gender").append(",").append("City")
.append(",").append("SampleDate").append(",").append("VirusType").append(",")
.append("SubType").append(",").append("Locus").append(",").append("Primer").append(",").append("GeneDirection")
.append(",").append("TypingMethod").append(",").append("DNASeq").append(",").append("AminoAcidSeq");
System.out.println(rs3.next());
while (rs3.next()) {
builder.append(System.lineSeparator());
builder.append(rs3.getString(1)).append(",").append(rs3.getString(2)).append(",")
.append(rs3.getString(3)).append(",").append(rs3.getString(5)).append(",")
.append(rs3.getString(7)).append(",").append(rs3.getString(10)).append(",")
.append(rs3.getString(11)).append(",").append(rs3.getString(12)).append(",")
.append(rs3.getString(13)).append(",").append(rs3.getString(14)).append(",")
.append(rs3.getString(15)).append(",").append(rs3.getString(16)).append(",").append(rs3.getString(17)).append(",");
}
bw.write(builder.toString());
} catch (IOException e) {
e.printStackTrace();
} catch (SQLException e1) {
e1.printStackTrace();
}
}
}

Start refactoring your code in small steps and then iteratively improve your design if needed.
As you have mentioned the algorithmic approach, leveraging that this should be your starting step.
CSV file from url,
then i bulk inserted into sql database,
then call data from SQL server and
display on Java console.
Finally select the column I want to keep
and export as a new CSV file.
Small helper functions for each of these steps.
Read more about SOLID design principles if that helps in improving your solution.

Can't Get Android to Append Data to .txt file

I'm pretty new here, and have been following all I could find on getting my program to append a series of numbers (determined from how often a button was pressed) to a .txt file whenever a timer runs out, but to no avail-I'm not sure what I'm missing...the app starts out by creating a .txt file in the downloads folder with a template in it:
String initialTemplate ="\"1\",\"2\",\"3\",\"4\",\"5\",\"6\",\"7\",\"8\",\"9\",\"10\",\"11\",\"12\"";
File path = Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_DOWNLOADS);
File file = new File(path, filename+".txt");
try {
FileOutputStream fos = new FileOutputStream(file);
fos.write(initialTemplate.getBytes());
fos.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
And then when a countdowntimer object finishes and restarts/ends, it triggers the class writeresults() to append the values:
if (CountsRemaining < 1){
textViewTime.setText("00:00:00");
cancel();
writeResults();
finishcount();
} else {
//append data
writeResults();
//Clear all variables
clearCounts();
start();
}
And the important part, to actually write the data, which is what isn't working:
public void writeResults(){
String Message = Count1 + ", " + Count2 + ", " + Count3 + ", " + Count4 + ", " + Count5 + ", " +
Count6 + ", " + Count7 + ", " + Count8 + ", " + Count9 + ", " + Count10 + ", " + Count11 + Count12;
FileWriter writer;
try {
File path = Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_DOWNLOADS);
File file = new File (path + filename+".txt");
writer = new FileWriter(file, true);
writer.append(Message);
writer.append("this is a writing test message");
writer.close();
Toast.makeText(getApplicationContext(), "Data Saved", Toast.LENGTH_SHORT).show();
} catch (IOException e) {
e.printStackTrace();
}
}
Any idea what I might be missing? Parameters?

The problem is in this line:
File file = new File (path + filename+".txt");
It should be like this, if you look at your first code, when creating file:
File file = new File (path, filename+".txt");

Java renameTo() leaving cifs* files on samba mount

I have a linux java program that is reading and writing to a CIFS mounted Windows file share. See code snippet at bottom.
After execution, there are files named "cifs*" left in the directory. If the target directory is on the local file system, the code works like a champ. However, if the target directory is a CIFS mounted Windows file share, I get the left-over files. I'm not sure what configuration changes I need to make to fix. Any help is greatly appreciated.
FileRenameMutex myFileRenameMutex = new FileRenameMutex("/WindowsMount/MoveLock");
class FileRenameMutex
{
// global variables
String lockFileBasename;
String unusedExtension = "_Unused";
String unusedFilename;
String inUseFilename;
String localMachineAddress;
String formattedTime;
// log4j logger for this class
public static Logger logMutex = Logger.getLogger(FileRenameMutex.class.getName());
public FileRenameMutex(String _lockFileBase) {
this.lockFileBasename = _lockFileBase;
logMutex.debug("FileRenameMutex: Constructor, with file " + lockFileBasename + " user = " + System.getProperty("user.name"));
try {
localMachineAddress = InetAddress.getLocalHost().getHostAddress();
//localMachineAddress = InetAddress.getLocalHost().getHostName();
} catch ( Exception e ) {
localMachineAddress = "UNKNOWN_HOST";
logMutex.error(" Could not determine host address. " + e.getMessage());
}
// set the file names
unusedFilename = lockFileBasename + unusedExtension;
inUseFilename = lockFileBasename + "_" + localMachineAddress;
logMutex.debug(" Local machine = " + localMachineAddress);
logMutex.debug(" Unused file name = " + this.unusedFilename);
logMutex.debug(" In Use file name = " + this.inUseFilename);
}
public boolean tryAcquire() throws InterruptedException {
boolean returnVal = false;
File unusedFile = new File(unusedFilename);
File inUseFile = new File(inUseFilename);
formattedTime = new Date().toString();
String inUseText = "This file created by the Alfresco cron job to MoveFileAndCreateDir "
+ "(move files from Unfiled to Filed folders).\n"
+ "Running on " + localMachineAddress + "\n Started at " + formattedTime + "\n";
try {
FileWriter fstream = new FileWriter(inUseFile);
BufferedWriter out = new BufferedWriter(fstream);
// attempt to rename file
logMutex.debug(" Attempting to rename mutex file " + unusedFilename + " to " + inUseFilename);
if ( unusedFile.renameTo(inUseFile) ) {
logMutex.debug(" Rename to inUse successful");
out.write(inUseText);
out.flush();
out.close();
returnVal = true; // lock was acquired
} else {
// System.out.println("Rename to inUse failed");
logMutex.error(" Rename of " + unusedFilename + " to " + inUseFilename + " failed in tryAcquire().");
}
} catch ( Exception e ) {
throw new InterruptedException("Error acquiring lock in tryAcquire(): " + e.getMessage());
}
return returnVal;
}
public void release() {
File unusedFile = new File(unusedFilename);
File inUseFile = new File(inUseFilename);
String unusedText = "This file was last by the Alfresco cron job to MoveFileAndCreateDir "
+ "Ran on " + localMachineAddress + "\n Started at " + formattedTime + "\n";
try {
FileWriter fstream = new FileWriter(inUseFile);
BufferedWriter out = new BufferedWriter(fstream);
out.write(unusedText);
out.flush();
out.close();
// attempt to rename file
logMutex.debug(" Attempting to rename active mutex file " + inUseFilename + " back to " + unusedFilename);
if ( inUseFile.renameTo(unusedFile) ) {
logMutex.debug(" Rename back to unused successful");
} else {
logMutex.error(" Rename of " + inUseFilename + " to " + unusedFilename + " failed in release().");
}
} catch ( Exception e ) {
logMutex.error("Error resetting lock file in release(): " + e.getMessage());
}
} // release()
} // end of class FileRenameMutex

Java Gui Text files Output

try {
String hour = (String) comboBox.getSelectedItem();
String filename = fileName.getText();
String date = ((JTextField)dateChooser.getDateEditor().getUiComponent()).getText();
String text = txtKeyword.getText();
String newline = "\n";
String directory = Directory.getText();
File path = new File(directory);
File[] faFiles = path.listFiles();
for(File file: faFiles){
**if(file.getName().contains(filename + "-" + date + "[" + hour + "]") == true == true || file.getName().contains(filename + "-" + date) || file.getName().contains(filename)){**
String line = null;
Reader reader = new InputStreamReader(new FileInputStream(file), "utf-8");
BufferedReader br = new BufferedReader(reader);
while ((line = br.readLine()) != null) {
if(line.contains(text)){
jTextArea1.append(line + newline);
btnClear.setEnabled(true);
btnExport.setEnabled(true);
}
}
br.close();
}
}
}
catch(Exception e){
}
Here is my question. I'm trying to use input and loop method to search for a file. The above code works but my problem is lets say I try to find 2 different text files
1. billing-20140527[09].txt has
a)XGMS,2014-05-27 10:08:04,122,PLAYER_VERIFY,VERIFY to LBA,0x580000,0xC0000,253040.
b)XGMS,2034-05-27 30:08:04,122,PLAYER_VERIFY,VERIFY to LBA,0x580000,0xC0000,253040.
2. billing-20140527[10].txt has
a)XCGS,2014-05-27 10:08:04,122,PLAYER_VERIFY,VERIFY to LBA,0x580000,0xC0000,253040.
b)HELO
**I try to find the number 1 in both text files, if lets say I input the text file name is
billing, I can find the number 1 in both text file and output them:**
a) XGMS,2014-05-27 10:08:04,122,PLAYER_VERIFY,VERIFY to LBA,0x580000,0xC0000,253040.
b) XCGS,2014-05-27 10:08:04,122,PLAYER_VERIFY,VERIFY to LBA,0x580000,0xC0000,253040.
**However, if I specify the text file name: billing-20140527[09].txt and find the number 1 inside the text file, it will only output:
a) XGMS,2014-05-27 10:08:04,122,PLAYER_VERIFY,VERIFY to LBA,0x580000,0xC0000,253040.**
Can anyone help me with this? Guide or help?

I would work with the BufferedReader. Because it reads a whole line. And then you can split the line by a delimiter (lets say a space " " ). In your case I would write a split-method which receives a String and search for the regex you want.

private void doSearch(File f2) throws IOException,
fileHandler.FileException {
File[] children = f2.listFiles();
if (children != null && searching)
for (int i = 0; i < children.length; i++) {
if (g.isReady()) {
g.setReady(false);
if (!searching) {
g.setReady(true);
break;
} else if (isDirectory(children[i])) {
g.getActualDirectoryInhalt().setText(children[i].getPath()
.substring(g.root.getText().length()));
counterDirectories++;
doSearch(children[i]);
} else if (advancedSearch && !filterSpecified(children[i])) {
raiseCounterForDirectorySize(children[i]);
continue;
} else if (checkFile(children[i])) {
counterFiles++;
searchThroughFile(children[i], this.regex);
raiseCounterForDirectorySize(children[i]);
} else {
g.getTextAreaUnreachable().setText(
g.getTextAreaUnreachable().getText() + f2
+ "\n");
raiseCounterForDirectorySize(children[i]);
}
} else {
doSearch(children[i]);
}
g.setReady(true);
}
}
And here's the other method:
public static void searchThroughFile(File f2, String regex) throws IOException,
fileHandler.FileException {
try {
InputStream is = new BufferedInputStream(new FileInputStream(f2));
String mimeType = URLConnection.guessContentTypeFromStream(is);
ArrayList<String> linesFromFile = fileHandler.FileReaderer
.readFileIntoStringArrayList(f2);
String line = null;
if (f2.getAbsolutePath().contains(regex)) {
g.getTextAreaAdvanced()
.setText(
g.getTextAreaAdvanced().getText()
+ f2.getPath() + "\n");
}
if (linesFromFile.size() != 0) {
for (int i = 0; i < linesFromFile.size(); i++) {
line = linesFromFile.get(i);
Pattern MY_Pattern = Pattern.compile(regex);
Matcher m = MY_Pattern.matcher(line);
if (!searching) {
break;
}
MarkOne: if (!g.isReady()) {
break MarkOne;
} else {
g.setReady(false);
}
while (m.find() && searching) {
counterFoundPattern++;
g.getFoundFilesInhalt().setText(counterFoundPattern + "");
if (mimeType != null) {
g.getTextAreaAdvanced().setText(
g.getTextAreaAdvanced().getText()
+ f2.getPath() + " " + m.group()
+ " " + mimeType + " " + i+1 + "\n");
} else {
g.getTextAreaAdvanced().setText(
g.getTextAreaAdvanced().getText()
+ f2.getPath() + " " + m.group()
+ " " + i+1 + "\n");
}
}
g.setReady(true);
}
}
} catch (IOException e) {
MarkOne: if (!g.isReady()) {
break MarkOne;
} else {
g.setReady(false);
}
g.getTabpane().setForegroundAt(2, Color.RED);
g.getTextAreaException().setText(
g.getTextAreaException().getText() + e + "\n");
g.setReady(true);
} catch (OutOfMemoryError oute) {
MarkOne: if (!g.isReady()) {
break MarkOne;
} else {
g.setReady(false);
}
g.getTextAreaException().setText(
g.getTextAreaException().getText() + "\n"
+ "Fatal Error encured! The File will be skipped!"
+ "\n" + f2.getAbsolutePath());
g.getTabpane().setSelectedIndex(2);
g.setReady(true);
return;
}
}

Unable to write to file using BufferedWriter

I have this Method that Lists the Files in a Directory and I need to write the same to a file. Apparently my
System.out.println();
is able to list the files and their Sizes and the Dates they were Modified. But My bufferedWriter Does not write Anything in the File. Here is My Method;
public void walk( String path, int limit ) throws IOException {
File root = new File( path );
File[] list = root.listFiles();
File rep = new File("report.txt");
SimpleDateFormat sdf = new SimpleDateFormat("MMM/dd/yyyy HH:mm:ss");
if (list == null) return;
long size;
BufferedWriter bw = new BufferedWriter(new FileWriter(rep));
for ( File f : list ) {
size = f.length()/1000/1000;
if ( f.isDirectory() ) {
walk( f.getAbsolutePath(), limit );
}
else {
if(size >= limit){
System.out.println( "File:" + f.getAbsoluteFile() + " " + size + "MB Last Modified Date: " + sdf.format(f.lastModified()));
bw.write("File:" + f.getAbsoluteFile() + " " + size + "MB Last Modified Date: " + sdf.format(f.lastModified()) + "\n");
}
}
}
bw.close();
}
What Am I Missing? I need to write the Out to the File report.txt but the file is empty.

I think it's because you're trying to open multiple buffered writers to the same file when it's calling itself through recursion. Try creating your writer outside of this method and pass it in as a parameter.
Example
public void myCallingMethod() throws IOException{
File rep = new File("report.txt");
BufferedWriter bw = new BufferedWriter(new FileWriter(rep));
walk("my/path", 4, bw);
bw.close();
}

Here's the code which might solve your problem.
I tried the same.
public class example {
public static void main(String[] args) throws IOException {
// Directory path here
String path = "C:\\";
SimpleDateFormat sdf = new SimpleDateFormat("MMM/dd/yyyy HH:mm:ss");
File folder = new File(path);
File[] listOfFiles = folder.listFiles();
File file = new File("report.txt");
if (!file.exists()) {
file.createNewFile();
}
FileWriter fw = new FileWriter(file.getAbsoluteFile());
BufferedWriter bw = new BufferedWriter(fw);
long size;
int limit = 2;
for (File f : listOfFiles) {
size = f.length() / 1000 / 1000;
if (size >= limit) {
System.out.println("File:" + f.getAbsoluteFile() + " " + size
+ "MB Last Modified Date: "
+ sdf.format(f.lastModified()));
bw.write("File:" + f.getAbsoluteFile() + " " + size
+ "MB Last Modified Date: "
+ sdf.format(f.lastModified()));
}
}
bw.close();
}
}

try to call the flush method after you called the write methode like:
bw.write("File:" + f.getAbsoluteFile() + " " + size + "MB Last Modified Date: " + sdf.format(f.lastModified()) + "\n");
bw.flush();
The flush method flushes your stream to your file

Define a variable like this
StringBuilder fileData = new StringBuilder();
And replace
bw.write("File:" + f.getAbsoluteFile() + " " + size + "MB Last Modified Date: " + sdf.format(f.lastModified()) + "\n");
bw.flush();
With
fileData.append("File:").append(f.getAbsoluteFile()).append(" ").append(size)
.append("MB Last Modified Date: ").append(sdf.format(f.lastModified()))
.append("\n") ;
And after the for loop write fileData to file
bw.write(fileData.toString());
bw.close();

You need to do a java.io.BufferedWriter#flush() before the close.