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How to speed up reading in input in Java

I am attempting to read in info from files to implement Dijkstra's algorithm. I believe that the double for loop is causing this to drastically slow down, is there anyway around this?
Edge[] edge = new Edge[127807];
int indexEdge = 0;
String line2 = "";
BufferedReader fileReader2 = new BufferedReader(new FileReader("Road.txt"));
String valueString = null;
String vertex1IDName = null;
String vertex2IDName = null;
String extra = null;
float value = 0;
int vertex1ID = 0;
int vertex2ID = 0;
//Read the file line by line
while ((line2 = fileReader2.readLine()) != null)
{
//Get all tokens available in line
String[] tokens2 = line2.split(DELIMITER);
for(String token1 : tokens2)
{
vertex1IDName = tokens2[0];
vertex2IDName = tokens2[1];
valueString = tokens2[2];
if(tokens2.length - 1 == 3) {
extra = tokens2[tokens2.length - 1];
}
else {
extra = "";
}
vertex1ID = Integer.parseInt(vertex1IDName);
vertex2ID = Integer.parseInt(vertex2IDName);
value = Float.parseFloat(valueString);
}
System.out.println("value: "+ value + " vertex1ID:"+ vertex1ID +" vertex2ID:"+ vertex2ID+ " extra:" + extra);
//if vertex 1 name or vertex 2 name in vertex.getID()
for(int i = 0; i< indexVertex; i++) {
for(int j = 0; j< indexVertex; j++) {
if(vertex1ID == vertex[i].getID() && vertex2ID == vertex[j].getID()) {
vertex[i].addNeighbour(edge[indexEdge] = new Edge(value,vertex[i],vertex[j],extra));
indexEdge++;
}
}
}
}

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);
}
}

Why can't I access my 2D array outside of the loop?

I'm having some trouble accessing my 2D array (myArray) outside of this the loop. I want to access it using other methods, but I can't even access it in this method. It prints out correctly as it's looping, but the test print of
System.out.println(myArray[10][2]);
is always null. So it's like the array isn't actually filling or something. Anyone know what I'm doing wrong here?
package titanic;
import java.io.*;
import java.util.*;
public class Titanic {
public static final int ROW = 1309;
public static final int COLUMN = 6;
public static String [][] myArray = new String[ROW][COLUMN];
public static String[][] arraySetup(){
int recordCounter = 0;
String[][] myArray = new String[ROW][COLUMN];
String[] name = new String [ROW];
try {
BufferedReader br = new BufferedReader(new FileReader("C:/Users/Tom/Desktop/Titanic.txt"));
String line;
for (int i = 0; i < 1309; i++){
while((line = br.readLine()) != null){
String tmp[] = line.split("\t");
myArray[i][0] = tmp[0];
myArray[i][1] = tmp[1];
myArray[i][2] = tmp[2];
myArray[i][3] = tmp[3];
myArray[i][4] = tmp[4];
myArray[i][5] = tmp[5];
System.out.println("myArray[i][5] = " + myArray[i][5]);
recordCounter++;
}
}
} catch (IOException e) {
e.printStackTrace();
}
System.out.println(myArray[10][2]);
System.out.println(recordCounter + " records.");
return myArray;
}

As you have you while loop inside for loop that is used to for indexing your output array while loop always writes into the myArray[0][0] to myArray[0][5]
for (int i = 0; i < 1309; i++){ // i is 0
while((line = br.readLine()) != null){ // you go through all the lines while i is 0
String tmp[] = line.split("\t");
myArray[i][0] = tmp[0];
myArray[i][1] = tmp[1];
myArray[i][2] = tmp[2];
myArray[i][3] = tmp[3];
myArray[i][4] = tmp[4];
myArray[i][5] = tmp[5];
System.out.println("myArray[i][5] = " + myArray[i][5]);
recordCounter++;
}
}
Because of that your check always returns null.
System.out.println(myArray[10][2]);

I think the problem in your code is right there
for (int i = 0; i < 1309; i++){ // you loop 1308 time
while((line = br.readLine()) != null){ /* in each loop, you loop
until you have read all the file so you read 1308 time the file. But when
you reach the end of file on the first iterration, it wont read the file on the 1307
other iterration and all data will be store in myArray[0][0-5]*/
String tmp[] = line.split("\t");
myArray[i][0] = tmp[0];
myArray[i][1] = tmp[1];
myArray[i][2] = tmp[2];
myArray[i][3] = tmp[3];
myArray[i][4] = tmp[4];
myArray[i][5] = tmp[5];
System.out.println("myArray[i][5] = " + myArray[i][5]);
recordCounter++;
}
}

Don't use for and while loop together. During the first for loop, your while reads all file contents and all other array positions remain empty.
Try this instead:
int i=0;
while ((line = br.readLine()) != null){
String tmp[] = line.split("\t");
myArray[i][0] = tmp[0];
myArray[i][1] = tmp[1];
...
myArray[i][5] = tmp[5];
i++;
System.out.println("myArray[i][5] = " + myArray[i][5]);
recordCounter++;
}

inefficient looping in java

This is my csv data:
Name,Code,Price,Colour,Type,Stock
A,1001,35000,Red,Car Paint,54
B,1002,56000,Blue,House Paint,90
As you can see, my coding is inefficient.
This is because all the textfields in netbeans do not allow same variable names, I have to give different variable names to each text field (Example: code1, code2, code3, name1, name2,name3)
Can someone help me on how to loop this data so they do it four times and i dont have to repeat the coding? and to skip the process if the fields are blank.
The following is my coding:
try
{
for(int z=0; z<4;z++)
{
String code1;
code1=this.text1.getText();
System.out.println("this is the code: " + code1);
String qty;
int qty1;
qty=this.quantity1.getText();
qty1=Integer.parseInt(qty);
System.out.println("quantity: "+qty1);
String code2;
code2=this.text2.getText();
System.out.println("this is the code: " + code2);
int qty2;
qty=this.quantity2.getText();
qty2=Integer.parseInt(qty);
System.out.println("quantity: "+qty2);
String code3;
code3=this.text3.getText();
System.out.println("this is the code: " + code3);
int qty3;
qty=this.quantity2.getText();
qty3=Integer.parseInt(qty);
System.out.println("quantity: "+qty3);
String code4;
code4=this.text4.getText();
System.out.println("this is the code: " + code4);
int qty4;
qty=this.quantity2.getText();
qty4=Integer.parseInt(qty);
System.out.println("quantity: "+qty4);
int sum=0;
BufferedReader line = new BufferedReader(new FileReader(new File("C:\\Users\\Laura Sutardja\\Documents\\IB DP\\Computer Science HL\\cs\\product.txt")));
String indata;
ArrayList<String[]> dataArr = new ArrayList<>();
String[] club = new String[6];
String[] value;
while ((indata = line.readLine()) != null) {
value = indata.split(",");
dataArr.add(value);
}
for (int i = 0; i < dataArr.size(); i++) {
String[] nameData = dataArr.get(i);
if (nameData[1].equals(code1)) {
System.out.println("Found name.");
name1.setText(""+ nameData[0]);
int price;
price=Integer.parseInt(nameData[2]);
int totalprice=qty1*price;
String total=Integer.toString(totalprice);
price1.setText(total);
sum=sum+totalprice;
break;
}
}
for (int i = 0; i < dataArr.size(); i++) {
String[] nameData = dataArr.get(i);
if (nameData[1].equals(code2)) {
System.out.println("Found name.");
name2.setText(""+ nameData[0]);
int price;
price=Integer.parseInt(nameData[2]);
int totalprice=qty2*price;
String total=Integer.toString(totalprice);
price2.setText(total);
sum=sum+totalprice;
break;
}
}
for (int i = 0; i < dataArr.size(); i++) {
String[] nameData = dataArr.get(i);
if (nameData[1].equals(code3)) {
System.out.println("Found name.");
name3.setText(""+ nameData[0]);
int price;
price=Integer.parseInt(nameData[2]);
int totalprice=qty3*price;
int totalprice3=totalprice;
String total=Integer.toString(totalprice);
price3.setText(total);
sum=sum+totalprice;
break;
}
}
for (int i = 0; i < dataArr.size(); i++) {
String[] nameData = dataArr.get(i);
if (nameData[1].equals(code4)) {
System.out.println("Found name.");
name4.setText(""+ nameData[0]);
int price;
price=Integer.parseInt(nameData[2]);
int totalprice=qty4*price;
int totalprice4=totalprice;
String total=Integer.toString(totalprice);
price4.setText(total);
sum=sum+totalprice;
break;
}
}
total1.setText("Rp. "+sum);
}
}
catch ( IOException iox )
{
System.out.println("Error");
}

Why don't you use a library like http://commons.apache.org/proper/commons-csv/

Solving this problem is actually rather straight forward if you break it down into separate parts.
First you need to solve the problem of loading the data into an internal data representation that is easy to use. Just loading the file into Java is rather simple and you have already done this:
BufferedReader csvFile = new BufferedReader(new FileReader(new File(path)));
String line = "start";
int count = 0;
while((line = csvFile.readLine()) != null){
System.out.println(line);
}
csvFile.close();
The next problem is splitting the line and store it in a meaningful way - for each line.
HashMap<Integer, String> record = new HashMap<Integer, String>();
String[] raw = line.split(",");
for(int i=0;i<raw.length; i++){
record.put(i, raw[i]);
}
Now you state you only want to store records that have non-empty fields so we need to check for that:
HashMap<Integer, String> record = new HashMap<Integer, String>();
String[] raw = line.split(",");
Boolean store = true;
for(int i=0;i<raw.length; i++){
if(raw[i].equals("") || raw[i].equals(null)){
store = false;
break;
}
record.put(i, raw[i]);
}
if(store)
csvData.add(record);
Now, you can load each record of the csv file as a dictionary that you can easily use. All that remains is to save a list of these dictionaries.
ArrayList<Map<Integer, String>> csvData = new ArrayList<Map<Integer, String>>();
BufferedReader csvFile = new BufferedReader(new FileReader(new File(path)));
String line = "start";
int count = 0;
while((line = csvFile.readLine()) != null){
if(count == 0){//skip first line
count++;
continue;
}
HashMap<Integer, String> record = new HashMap<Integer, String>();
String[] raw = line.split(",");
Boolean store = true;
for(int i=0;i<raw.length; i++){
if(raw[i].equals("") || raw[i].equals(null))
{
store = false;
break;
}
record.put(i, raw[i]);
}
if(store)
csvData.add(record);
}
csvFile.close();
Full code snippet that loads in data and easily access whatever information you want:
public class Main {
public static final int NAME = 0;
public static final int CODE = 1;
public static final int PRICE = 2;
public static final int COLOR = 3;
public static final int TYPE = 4;
public static final int STOCK = 5;
public static void main(String[] args) throws IOException{
ArrayList<Map<Integer, String>> csvData = loadCSVFile("C:\\path\\to\\file\\products.txt");
//Print some of the data
System.out.println("---------------------------");
for(Map<Integer, String> record : csvData){
printInfo(record);
}
}
public static ArrayList<Map<Integer, String>> loadCSVFile(String path) throws IOException{
ArrayList<Map<Integer, String>> csvData = new ArrayList<Map<Integer, String>>();
BufferedReader csvFile = new BufferedReader(new FileReader(new File(path)));
String line = "start";
int count = 0;
while((line = csvFile.readLine()) != null){
if(count == 0){
count++;
continue;
}
HashMap<Integer, String> record = new HashMap<Integer, String>();
String[] raw = line.split(",");
Boolean store = true;
for(int i=0;i<raw.length; i++){
if(raw[i].equals("") || raw[i].equals(null))
{
store = false;
break;
}
record.put(i, raw[i]);
}
if(store)
csvData.add(record);
}
csvFile.close();
return csvData;
}
public static void printInfo(Map<Integer, String> record){
System.out.println(record.get(CODE) + " : " + record.get(TYPE));
System.out.println(record.get(NAME) + " : " + record.get(STOCK) + " : " + record.get(PRICE));
System.out.println("---------------------------");
}
}

Searching in arraylist<String[]> from user input

I want to search in an arraylist from a user input but my if condition doesn't seem to work. Using boolean and .contains() doesn't work for my programme either. This is the coding:
String phone;
phone=this.text1.getText();
System.out.println("this is the phone: " + phone);
BufferedReader line = new BufferedReader(new FileReader(new File("C:\\Users\\Laura Sutardja\\Documents\\IB DP\\Computer Science HL\\cs\\data.txt")));
String indata;
ArrayList<String[]> dataArr = new ArrayList<String[]>();
while ((indata = line.readLine()) != null) {
String[] club = new String[2];
String[] value = indata.split(",", 2);
//for (int i = 0; i < 2; i++) {
int n = Math.min(value.length, club.length);
for (int i = 0; i < n; i++) {
club[i] = value[i];
}
boolean aa = dataArr.contains(this.text1.getText());
if(aa==true)
text2.setText("The data is found.");
else
text2.setText("The data is not found.");
dataArr.add(club);
}
for (int i = 0; i < dataArr.size(); i++) {
for (int x = 0; x < dataArr.get(i).length; x++) {
System.out.printf("dataArr[%d][%d]: ", i, x);
System.out.println(dataArr.get(i)[x]);
}
}
}
catch ( IOException iox )
{
System.out.println("Error");
}

Your dataArr is a list of String[], and you are searching for a String. The two are different kind of objects.
I don't really know how the content of the club array looks like, but you should either change dataArr in order to hold plain String, or to write a method which looks iteratively in dataArr for a String[] containing the output of this.text1.getText().

There is a lot wrong with the program. I assume you want to read a textfile and store each line in the arraylist. To do this you have to split each line of the textfile and store that array in the arrayList.
String[] value;
while ((indata = line.readLine()) != null) {
value = indata.split(",");
dataArr.add(value);
}
Now you have the contents of the file in the arrayList.
Next you want to compare the userinput with each element of the arraylist.
int j = 0;
for (int i = 0; i < dataArr.size(); i++) {
String[] phoneData = dataArr.get(i);
if (phoneData[1].equals(phone)) { // i am assuming here that the phone number is the 2nd element of the String[] array, since i dont know how the textfile looks.
System.out.println("Found number.");
club[j++] = phoneData[1];
} else if (i == dataArr.size()-1) {
System.out.println("Didn't find number.");
}
}
Edit:
As requested:
String phone;
phone = "38495";
System.out.println("this is the phone: " + phone);
BufferedReader line = new BufferedReader(new FileReader(new File("list.txt")));
String indata;
ArrayList<String[]> dataArr = new ArrayList<>();
String[] club = new String[2];
String[] value;// = indata.split(",", 2);
while ((indata = line.readLine()) != null) {
value = indata.split(",");
dataArr.add(value);
}
int j = 0;
for (int i = 0; i < dataArr.size(); i++) {
String[] phoneData = dataArr.get(i);
if (phoneData[1].equals(phone)) {
System.out.println("Found number.");
club[j++] = phoneData[1];
break;
} else if (i == dataArr.size()-1) {
System.out.println("Didn't find number.");
}
}
I hope this makes sense now.