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Highlight specific text in JTextArea - Java

I'm trying to quickly highlight my specific text in JTextArea. The code I need is running too slow, and I would like to know if there is a faster way to highlight text without crashing the whole application.
I have over 5000 words to scroll through and see if there is a need to highlight them or not, but this code doesn't work great for me. I'm looking for a better way to do it. This is my code:
class MyHighlightPainter extends DefaultHighlighter.DefaultHighlightPainter
{
public MyHighlightPainter(Color color) {
super(color);
}
}
Highlighter.HighlightPainter myHighlightPainter = new MyHighlightPainter(Color.yellow);
public void Highligh(JTextComponent textComp, String pattern)
{
try {
Highlighter hilite = textComp.getHighlighter();
Document doc = textComp.getDocument();
String text = doc.getText(0, doc.getLength());
for(int pos = 0; (pos=text.toUpperCase().indexOf(pattern.toUpperCase(),pos))>=0; pos += pattern.length())
hilite.addHighlight(pos, pos+pattern.length(), myHighlightPainter);
} catch (Exception e) {}
}
public void keyReleased(KeyEvent arg0) {
String text = vocabolario.getText();
String[] parziale = new String[5000];
try {
String p1 = "SELECT definizione FROM Cherubini WHERE definizione LIKE '%", p2 = "%';", px = vocabolario.getText(), query = p1+px+p2;
ResultSet rs = Main.conn().createStatement().executeQuery(query);
while(rs.next())
{
String[] dati = { rs.getString("definizione") };
for(int i = 0; i < dati.length; i++) { parziale[i] = dati[i]; textArea.append(parziale[i]+"\n"); }
}
}
catch(SQLException exc) {}
Highligh(textArea,vocabolario.getText());
}
});

for(int pos = 0; (pos=text.toUpperCase().indexOf(pattern.toUpperCase(),pos))>=0; pos += pattern.length())
Why do you keep converting the data to upper case? This should only be done once:
String upperText = text.toUpperCase();
String upperPattern = pattern.toUpperCase();
for(int pos = 0; (pos = upperText.indexOf(upperPattern, pos)) >= 0; pos += pattern.length())

Speed up reading CSV in Java

I have a relatively inefficent CSVReader code, see below. It takes more than 30 seconds to read 30000+ lines. How to speed up this reading process as fast as possible?
public class DataReader {
private String csvFile;
private List<String> sub = new ArrayList<String>();
private List<List> master = new ArrayList<List>();
public void ReadFromCSV(String csvFile) {
String line = "";
String cvsSplitBy = ",";
try (BufferedReader br = new BufferedReader(new FileReader(csvFile))) {
System.out.println("Header " + br.readLine());
while ((line = br.readLine()) != null) {
// use comma as separator
String[] list = line.split(cvsSplitBy);
// System.out.println("the size is " + country[1]);
for (int i = 0; i < list.length; i++) {
sub.add(list[i]);
}
List<String> temp = (List<String>) ((ArrayList<String>) sub).clone();
// master.add(new ArrayList<String>(sub));
master.add(temp);
sub.removeAll(sub);
}
} catch (IOException e) {
e.printStackTrace();
}
System.out.println(master);
}
public List<List> getMaster() {
return master;
}
}
UPDATE: I have found that my code actually can finish the reading work in less than 1 second if run it separately. As this DataReader is a part used by my simulation model to initialize the relevant properties. And the following part is associated with the use of the data imported, WHICH TAKES 40 SECONDS TO FINISH! Anyone could help by looking at the generic part of the codes?
// add route network
Network<Object> net = (Network<Object>)context.getProjection("IntraCity Network");
IndexedIterable<Object> local_hubs = context.getObjects(LocalHub.class);
for (int i = 0; i <= CSV_reader_route.getMaster().size() - 1; i++) {
String source = (String) CSV_reader_route.getMaster().get(i).get(0);
String target = (String) CSV_reader_route.getMaster().get(i).get(3);
double dist = Double.parseDouble((String) CSV_reader_route.getMaster().get(i).get(6));
double time = Double.parseDouble((String) CSV_reader_route.getMaster().get(i).get(7));
Object source_hub = null;
Object target_hub = null;
Query<Object> source_query = new PropertyEquals<Object>(context, "hub_code", source);
for (Object o : source_query.query()) {
if (o instanceof LocalHub) {
source_hub = (LocalHub) o;
}
if (o instanceof GatewayHub) {
source_hub = (GatewayHub) o;
}
}
Query<Object> target_query = new PropertyEquals<Object>(context, "hub_code", target);
for (Object o : target_query.query()) {
if (o instanceof LocalHub) {
target_hub = (LocalHub) o;
}
if (o instanceof GatewayHub) {
target_hub = (GatewayHub) o;
}
}
// System.out.println(target_hub.getClass() + " " + time);
// Route this_route = (Route) net.addEdge(source_hub, target_hub);
// context.add(this_route);
// System.out.println(net.getEdge(source_hub, target_hub));
if (net.getEdge(source, target) == null) {
Route this_route = (Route) net.addEdge(source, target);
context.add(this_route);
// this_route.setDist(dist);
// this_route.setTime(time); }
}
}

In your code you are doing many write operation to just add the list of values from current row in your master list which is not required. You can replace the existing code with simple one as given below.
Existing code:
String[] list = line.split(cvsSplitBy);
// System.out.println("the size is " + country[1]);
for (int i = 0; i < list.length; i++) {
sub.add(list[i]);
}
List<String> temp = (List<String>) ((ArrayList<String>) sub).clone();
// master.add(new ArrayList<String>(sub));
master.add(temp);
sub.removeAll(sub);
Suggested code:
master.add(Arrays.asList(line.split(cvsSplitBy)));

I don't have a CSV that big, but you could try the following:
public static void main(String[] args) throws IOException {
Path csvPath = Paths.get("path/to/file.csv");
List<List<String>> master = Files.lines(csvPath)
.skip(1)
.map(line -> Arrays.asList(line.split(",")))
.collect(Collectors.toList());
}
EDIT: I tried it with a CSV sample with 50k entries and the code runs in less than one second.

With extends to the answer of #Alex R, you can process it in parallel as well like this:
public static void main(String[] args) throws IOException {
Path csvPath = Paths.get("path/to/file.csv");
List<List<String>> master = Files.lines(csvPath)
.skip(1).parallel()
.map(line -> Arrays.asList(line.split(",")))
.collect(Collectors.toList());
}

How to apply for loop on first n vlalues of arraylist

I have an arraylist in which I have ESSID, BSSID, Strenght of access Point on first three indexes, and from Index 4 to 6 I have again ESSID, BSSID, Strength of another AccessPoint. I want to store this list in database like first three values save in one row of table. and next three values save in 2nd row of table.
String[] namesArr = new String[arrayList2.size()]; //conver arraylist to array
for (int j = 0; j < arrayList2.size(); j++){
namesArr[j] = arrayList2.get(j);
int length = namesArr[j].length();
for (int k = 0; k < length; k += 3) {
ssid = namesArr[k];
bssid = namesArr[k + 1];
rssid = namesArr[k + 2];
}
insertValues(this);
}
public void insertValues(View.OnClickListener view){
SendData send = new SendData(this);
send.execute(bssid,ssid,rssid);}
I have made a class to store this data in database that works fine.
public class SendData extends AsyncTask<String, Void, String> {
AlertDialog dialog;
Context context;
public SendData(Context context) {
this.context = context;
}
#Override
protected void onPreExecute() {
dialog = new AlertDialog.Builder(context).create();
dialog.setTitle("Message");
}
#Override
protected void onPostExecute(String s) {
dialog.setMessage(s);
dialog.show();
}
#Override
protected String doInBackground(String... voids) {
String data = "";
String result = "";
String MAC = voids[0];
String Name = voids[1];
String Strength = voids[2];
String con_Str = "http://10.5.48.129/Webapi/accesspoints_data/create.php";
try{
URL url = new URL(con_Str);
HttpURLConnection http = (HttpURLConnection) url.openConnection();
http.setRequestMethod("POST");
http.setDoInput(true);
http.setDoOutput(true);
OutputStream out_Stream = http.getOutputStream();
BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(out_Stream, "UTF-8"));
JSONObject obj = new JSONObject();
try {
obj.put("BSSID", MAC);
obj.put("ESSID", Name);
obj.put("RSSID", Strength);
} catch (JSONException e) {
e.printStackTrace();
}
data = obj.toString();
writer.write(data);
writer.flush();
writer.close();
out_Stream.close();
InputStream in_Stream = http.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(in_Stream, "ISO-8859-1"));
String line = "";
while ((line = reader.readLine()) != null)
{
result += line;
}
reader.close();
in_Stream.close();
http.disconnect();
return result;
} catch (MalformedURLException e){
result = e.getMessage();
} catch (IOException e){
result = e.getMessage();
}
return result;
}
}
SendData class is perfectly working but problem is with for loop.

I think this is result that you are expecting :
List<String> arrayList2 = new ArrayList<>();
arrayList2.add("1");
arrayList2.add("2");
arrayList2.add("3");
arrayList2.add("4");
arrayList2.add("5");
arrayList2.add("6");
arrayList2.add("6");
arrayList2.add("7");
arrayList2.add("8");
arrayList2.add("9");
arrayList2.add("10");
List<String[]> sarrayList = new ArrayList<>();
String[] arr = new String[3];
int i = 0;
for (int j = 0; j < arrayList2.size(); j++)
{
arr[i] = arrayList2.get(j);
i++;
if((j+1)%3==0)
{
sarrayList.add(arr);
i = 0;
arr = new String[3];
}
}
for(String [] sa:sarrayList)
{
for(String s:sa)
{
System.out.println(s);
}
System.out.println("=========");
}
This might not be the most efficient way of doing it. But it splits the ArrayList in to String arrays of length=3 and stores them in a new ArrayList named sarrayList

I would advise to use a datastructure to hold the record. See the code below this is a small example how you could do it
ArrayList<Record> records;
for (int i = 2; i < inputArrayList.size(); i = i + 3){
string ssid = namesArr.get(i - 2);
string bssid = namesArr.get(i - 1);
string rssid = namesArr.get(i);
records.add(new Record(ssid, bssid, rssid));
}
class Record{
string ssid;
string bssid;
string rssid;
// Constructor...
// Getter and setter to be implemented...
}

ok from what i understand you want to divide the arraylist each 3 elements thats how you do it with streams and it will return an a collection of arraylists each one has 3 elements
final int chunkSize = 3;
final AtomicInteger counter = new AtomicInteger();
//arrayList here us your array list
final Collection<List<String>> result = arrayList.stream()
.collect(Collectors.groupingBy(it -> counter.getAndIncrement() / chunkSize))
.values();
and mentioning supermar10 answer you code make a class to map the strings to it like that
class Record{
string ssid;
string bssid;
string rssid;
Record(String ssid,String bssid,String rssid){
this.ssid=ssid;
this.bssid=bssid;
this.rssid=rssid;
}
}
now you have a class to map to now save the records in a list of Record
create a a list in the main class
static List<Record> lists=new ArrayList<>();
then map the data like that
result.stream().forEach(nowList -> saveRecord(nowList));
and thats the save method
static void saveRecord(List<String> list){
lists.add(new Record(list.get(0),list.get(1),list.get(2)));
}

I have simplified it to one loop and also modified insertValues so that it takes 3 more parameters. This
int size = arrayList2.size();
for (int j = 0; j < size; j += 3) {
if (size - j < 3 ) {
break;
}
String ssid = arrayList2.get(j);
String bssid = arrayList2.get(j + 1);
String rssid = arrayList2.get(j + 2);
insertValues(this, ssid, bssid, rssid);
}
if one the other hand ssid and so on are class variables the inside of the loop can be changed to
ssid = arrayList2.get(j);
bssid = arrayList2.get(j + 1);
rssid = arrayList2.get(j + 2);
insertValues();

How to display Object array in JTable?

This is my code which I am using but when I am trying to print dataArray object, then data is not show in JTable. Which model properties of table to print Object array values can used and how?
public class ShowAddressForm extends javax.swing.JFrame {
Object data[][];
Object dataArray[][];
int count = 0;
String st;
public ShowAddressForm(String fname , String str) {
super(fname);
st = str;
initComponents();
fillTable();
}
public void fillTable()
{
int count = 0;
String str;
try
{
BufferedReader br = new BufferedReader(new FileReader("D:\\JavaPrograms\\Contact Management System\\InputFiles\\AddressFile"));
while((str = br.readLine()) != null)
{
count++;
}
br.close();
} catch (Exception e)
{
}
Object id;
Object name;
data = new Object[count][7];
int i = 0 , j = 0 , m;
try
{
BufferedReader buffrea = new BufferedReader(new FileReader("D:\\JavaPrograms\\Contact Management System\\InputFiles\\AddressFile"));
while((str = buffrea.readLine()) != null)
{
StringTokenizer token = new StringTokenizer(str , "*");
int n = token.countTokens();
id = token.nextElement();
name = token.nextElement();
String strNameLow = name.toString().toLowerCase();
String strNameUpp = name.toString().toUpperCase();
if(strNameLow.startsWith(st.toLowerCase()) || strNameUpp.startsWith(st.toUpperCase()))
{
data[i][0] = id;
data[i][1] = name;
for(j = 2 ; j < n ; j++)
{
data[i][j] = token.nextElement();
}
i = i + 1;
}
}
buffrea.close();
} catch(IOException ioe){
System.out.println("Error : " + ioe.toString());
}
dataArray = new Object[i][7];
for(int a = 0 ; a < i ; a++)
{
for(int b = 0 ; b < 7 ; b++)
{
dataArray[a][b] = data[a][b];
}
}
//Here is the code to print dataArray object which i used but it is not working, when i am run my program it is print "[Ljava.lang.Object;#1cc2e30" in table's first cell[0][0] position
DefaultTableModel model = (DefaultTableModel)this.data_table.getModel();
model.addRow(dataArray);
}

I filled data in a JTable like this. You might want to give it a try adapting it to your code. Variable and stuff are in spanish, just replace them with what you need. In my case it's a table with 4 columns representing a date, a score, duration and max viewers.
private void fillJTable(){
//creating data to add into the JTable. Here you might want to import your proper data from elsewhere
Date date = new Date();
UserReplay rep1 = new UserReplay(date, 12, 13,14);
UserReplay rep2 = new UserReplay(date, 2,34,5);
ArrayList<UserReplay> usuaris = new ArrayList<>();
usuaris.add(rep1);
usuaris.add(rep2);
//----Filling Jtable------
DefaultTableModel model = (DefaultTableModel) view.getTable().getModel();
model.addColumn("Fecha");
model.addColumn("Puntuación");
model.addColumn("Tiempo de duración");
model.addColumn("Pico máximo de espectadores");
for (int i = 0; i < usuaris.size(); i++){
Vector<Date> fecha = new Vector<>(Arrays.asList(usuaris.get(i).getDate()));
Vector<Integer> puntuacion = new Vector<>(Arrays.asList(usuaris.get(i).getPuntuacion()));
Vector<Integer> tiempo = new Vector<>(Arrays.asList(usuaris.get(i).getTiempo()));
Vector<Integer> espectadors = new Vector<>(Arrays.asList(usuaris.get(i).getTiempo()));
Vector<Object> row = new Vector<Object>();
row.addElement(fecha.get(0));
row.addElement(puntuacion.get(0));
row.addElement(tiempo.get(0));
row.addElement(espectadors.get(0));
model.addRow(row);
}
}

How to modify the iterator when hashset values are added

I have written code for to find out the broken links present in the website using selenium webdriver in java. As links are getting added in the HashSet while launching the different urls. I have tried to read the added urls from HashSet it stops executing after sometime. This is happening because iterator remains as it is even adding of new links to the HashSet. I want that execution should continue for all links present in the HashSet.
[I have tried to convert Set to an array but duplicate links are executing multiple times.]
public Set<String> unique_links;
HashMap<String, String> result;
Set<String> finalLinkSet = new HashSet<>();
Set<String> hs = new HashSet<>();
Set<String> uniqueLinkSet = new HashSet<>();
// String[] finalLinkArray;
String[] finalLinkArray;
boolean isValid = false;
FileWriter fstream;
BufferedWriter out;
int count = 1;
int FC = 0;
Set<String> secondaryset = new HashSet<>();
// String Responsecode = null;
#Test
public void LinkTesting() throws IOException, RowsExceededException,
WriteException {
w.manage().deleteAllCookies();
unique_links = new HashSet<String>();
w.get("http://www.skyscape.com");
ArrayList<WebElement> urlList = new ArrayList<WebElement>();
urlList = (ArrayList<WebElement>) w.findElements(By.tagName("a"));
setFinalLinkSet(getUniqueList(urlList));
for(Iterator<String> i = finalLinkSet.iterator(); i.hasNext(); ) {
System.out.println(finalLinkSet.size());
String currenturl = (String) i.next();
if ((currenturl.length() > 0 && currenturl
.startsWith("http://www.skyscape.com"))) {
if (!currenturl.startsWith("http://www.skyscape.com/estore/")&&
(!currenturl.startsWith("http://www.skyscape.com/demos/"))) {
System.out.println(currenturl);
getResponseCode(currenturl);
}
}
}
writetoexcel();
}
public void setFinalLinkSet(Set<String> finalLinkSet) {
this.finalLinkSet = finalLinkSet;
}
// function to get link from page and return array list of links
public Set<String> getLinksOnPage(String url) {
ArrayList<WebElement> secondaryUrl = new ArrayList<WebElement>();
secondaryUrl = (ArrayList<WebElement>) w.findElements(By.tagName("a"));
for (int i = 0; i < secondaryUrl.size(); i++) {
secondaryset.add((secondaryUrl.get(i).getAttribute("href")
.toString()));
}
return secondaryset;
}
// function to fetch link from array list and store unique links in hashset
public Set<String> getUniqueList(ArrayList<WebElement> url_list) {
for (int i = 0; i < url_list.size(); i++) {
uniqueLinkSet.add(url_list.get(i).getAttribute("href").toString());
}
return uniqueLinkSet;
}
public boolean getResponseCode(String url) {
boolean isValid = false;
if (result == null) {
result = new HashMap<String, String>();
}
try {
URL u = new URL(url);
w.navigate().to(url);
HttpURLConnection h = (HttpURLConnection) u.openConnection();
h.setRequestMethod("GET");
h.connect();
System.out.println(h.getResponseCode());
if ((h.getResponseCode() != 500) && (h.getResponseCode() != 404)
&& (h.getResponseCode() != 403)
&& (h.getResponseCode() != 402)
&& (h.getResponseCode() != 400)
&& (h.getResponseCode() != 401)) {
// && (h.getResponseCode() != 302)) {
//getLinksOnPage(url);
Set<String> unique2 = getLinksOnPage(url);
setFinalLinkSet(unique2);
result.put(url.toString(), "" + h.getResponseCode());
} else {
result.put(url.toString(), "" + h.getResponseCode());
FC++;
}
return isValid;
} catch (Exception e) {
}
return isValid;
}
private void writetoexcel() throws IOException, RowsExceededException,
WriteException {
FileOutputStream fo = new FileOutputStream("OldLinks.xls");
WritableWorkbook wwb = Workbook.createWorkbook(fo);
WritableSheet ws = wwb.createSheet("Links", 0);
int recordsToPrint = result.size();
Label HeaderUrl = new Label(0, 0, "Urls");
ws.addCell(HeaderUrl);
Label HeaderCode = new Label(1, 0, "Response Code");
ws.addCell(HeaderCode);
Label HeaderStatus = new Label(2, 0, "Status");
ws.addCell(HeaderStatus);
Iterator<Entry<String, String>> it = result.entrySet().iterator();
while (it.hasNext() && count < recordsToPrint) {
String Responsecode = null;
Map.Entry<String, String> pairs = it.next();
System.out.println("Value is --" + pairs.getKey() + " - "
+ pairs.getValue() + "\n");
Label Urllink = new Label(0, count, pairs.getKey());
Label RespCode = new Label(1, count, pairs.getValue());
Responsecode = pairs.getValue();
System.out.println(Responsecode);
if ((Responsecode.equals("500")) || (Responsecode.equals("404"))
|| (Responsecode.equals("403"))
|| (Responsecode.equals("400"))
|| (Responsecode.equals("402"))
|| (Responsecode.equals("401"))) {
// || (Responsecode.equals("302"))) {
Label Status1 = new Label(2, count, "Fail");
ws.addCell(Status1);
} else {
Label Status2 = new Label(2, count, "Pass");
ws.addCell(Status2);
}
try {
ws.addCell(Urllink);
} catch (RowsExceededException e) {
e.printStackTrace();
} catch (WriteException e) {
e.printStackTrace();
}
ws.addCell(RespCode);
count++;
}
Label FCS = new Label(4, 1, "Fail Urls Count is = " + FC);
ws.addCell(FCS);
wwb.write();
wwb.close();
}
}

In short, as far as I understand the problem: You have (at least) two threads (although I couldn't find them in the too long code example), one is adding entries to the HashSet, and the other should continuously list elements as they are added to the HashSet.
1st: You should use a concurrent data structure for this, but not a simple HashSet.
2nd: Iterators of HashSet do not support concurrent modification, so you can now have an iterator "waiting" for new entries being added.
Best is to change your code to use some kind of event-message pattern (sometimes also called broadcaster/listener), where the finding of a new URL generates an event, that other parts of your code listen to and then write them to the file.

Your loop finishes (earlier than desired) for the following reasons:
The initiation part Iterator<String> i = finalLinkSet.iterator()of your for-loop
for(Iterator<String> i = finalLinkSet.iterator(); i.hasNext(); ) {
is evaluated once when the loop is started. Hence it will not react on changes to finalLinkSet even if there where some.
You are not making any changes to finalLinkSet. Instead you are overwriting it with a new set when calling
setFinalLinkSet(unique2);
So instead you should:
Use a list, so you have ordered elements. (Adding entries to an unordered set will make it impossible to know which ones you already have iterated over). I suggest you therefore use an ArrayList<String>, so you have constant access time by the little drawback of performance for resizing on adding new entries.
Modify your for-loop to use an index, so evaluating the init-part once is sufficient and you can react on the changing size of list:
for(int i = 0; i < finalLinkList.size(); i++) {
System.out.println(finalLinkSet.size());
String currenturl = (String) finalLinkList.get(i);
Then instead of overwriting the list you should:
// for both occurrences
addToFinalLinkList(...); // see new code below
and
public void addToFinalLinkList(Set<String> tempSet) {
for(String url: tempSet)
{
if(!finalLinkList.contains(url))
finalListList.add(url);
}
}
I know this is not best from the performance point of view, but since you are inside a test, this shouldn't be a problem from what I see...