I am trying to save the contents of a word file line by line into a LinkedList.
What am I doing wrong? The console is showing that it is definatley reading the file but not saving its contents?
public class SpellCheck {
LinkedList<String> lines = new LinkedList();
boolean suggestWord ;
public static void main(String[] args) throws java.io.IOException{
System.out.println("Welcome to the spellchecker");
LinkedList<String> list = new LinkedList<String>();
try {
File f = new File("input/dictionary.txt");
FileReader r = new FileReader(f);
BufferedReader reader = new BufferedReader(r);
String line = null;
String word = new String();
while((line = reader.readLine()) != null)
{
list.add(word);
word = new String();
}
reader.close();
}catch(IOException e) {
e.printStackTrace();
}
for(int i = 0; i<list.size();i++){
System.out.println(list.get(i));
}
}
}
You are adding word which is an empty string instead of adding line which you read from file:
String word = new String();
while((line = reader.readLine()) != null)
{
list.add(word);
^^^^^
word = new String();
}
It should be:
while((line = reader.readLine()) != null) {
list.add(line);
}
Related
I am trying to read txt file and then store splitted value in then array, and print all txt file value. But it is not printing the values.
This is how txt file value display as below:
"1675683811","590483002"
"2002199221","876015525"
Following are my code:
String st;
BufferedReader Br = null;
File objFile = new File("C:\\DATA\\File.txt");
Br = new BufferedReader(new FileReader(objFile));
while ((st = Br.readLine()) != null) {
String value = st.replace("\"", "");
String[] arraylist = StringUtils.split(value, ",");
for (int i = 0; i <= 1; i++) {
System.out.println(arraylist[i]);
}
}
Br.close();
Maybe try to write code like below. I changed declaration of split and also way of showing values, because your way could make exception at objects arraylist:
String st;
BufferedReader Br = null;
File objFile = new File("C:\\data\\file.txt");
Br = new BufferedReader(new FileReader(objFile));
while ((st = Br.readLine()) != null) {
String value = st.replace("\"", "");
String[] arraylist = value.split(",");
for (String row : arraylist) {
System.out.println(row);
}
}
Br.close();
A small change to your code, you can just use String.split method and your for loop will always throws ArrayOutOfBound exception
String st;
BufferedReader Br = null;
File objFile = new File("/Users/a602782/input.txt");
Br = new BufferedReader(new FileReader(objFile));
while ((st = Br.readLine()) != null) {
String value = st.replace("\"", "");
String[] arraylist = value.split(",");
for (int i = 0; i <arraylist.length; i++) {
System.out.println(arraylist[i]);
}
}
Br.close();
And if you want to print each digit on each line you can loop it again inside of for loop
String st;
BufferedReader Br = null;
File objFile = new File("/Users/a602782/input.txt");
Br = new BufferedReader(new FileReader(objFile));
while ((st = Br.readLine()) != null) {
String value = st.replace("\"", "");
String[] arraylist = value.split(",");
for (int i = 0; i <arraylist.length; i++) {
System.out.println(arraylist[i]);
for (char c:arraylist[i].toCharArray()) {
System.out.println(c);
}
}
}
Br.close();
My target is i have one txt file it contains some line of text. in this i have two words i.e A and 1. if line has "A" letter then next lines goto one file until next line contain "1" and if line contain "1" then next lines goto other file until "A" find.
Input file like follows
A
rahu
pahdu
jhaani
1
hjsdh
dhj
A
jiko
raju
A
tenk
kouou
I am expecting output
A.txt contain
rahu
pahdu
jhaani
Same
1.txt
My code
{
fis = new FileInputStream("E:\\Input.txt");
reader = new BufferedReader(new InputStreamReader(fis));
System.out.println("Reading File line by line using BufferedReader");
String line = reader.readLine();
while(line != null){
if(line.contains("LETTER00~VSAQCCCC~H~")) {
line = reader.readLine();
System.out.println(line);
}
else {
line= reader.readLine();
}
}
}
You could just repoint your FileOutputStream whenever you find a 1 or A.
public static void main(String[] args) throws IOException {
FileInputStream fis = new FileInputStream("in.txt");
BufferedReader reader = new BufferedReader(new InputStreamReader(fis));
FileOutputStream fosA = new FileOutputStream("out_A.txt");
FileOutputStream fos1 = new FileOutputStream("out_1.txt");
FileOutputStream fos = null;
System.out.println("Reading File line by line using BufferedReader");
String line = reader.readLine();
while (line != null) {
System.out.println(line);
if(line.equals("A"))
{
fos = fosA;
line = reader.readLine();
continue;
}
if(line.equals("1"))
{
fos = fos1;
line = reader.readLine();
continue;
}
fos.write(line.getBytes());
fos.write('\n');
fos.flush();
line = reader.readLine();
}
fos.close();
fosA.close();
fos1.close();
}
You can do something like this.
System.out.println("Reading File line by line using
BufferedReader");
String inputFIle = "";
String line;
boolean flag = false;
// String line = reader.readLine();
while ((line = reader.readLine()) != null) {
if (line.trim().equalsIgnoreCase("A")) {
inputFIle = "A.txt";
} else if(line.trim().equalsIgnoreCase("1")){
inputFIle = "1.txt";
}
else{
write(line, inputFIle);
}
}
You can do something like this
public static void main(String[] args) throws IOException {
Scanner scanner = new Scanner(new FileReader("Input.txt"));
boolean isFound = false;
List<String> main_list = new ArrayList<>();
List<String> sub_list = new ArrayList<>();
while(scanner.hasNextLine()){
String line = scanner.nextLine();
if(line.contains("A")) {
isFound = true;
} else if(line.contains("1")) {
isFound = false;
for (String aSub_list : sub_list) {
main_list.add(aSub_list);
}
sub_list.clear();
}
if(isFound && !line.contains("A")) {
sub_list.add(line);
}
}
for (String aMain_list : main_list) {
System.out.println(aMain_list);
}
}
I have some CSV file with the same column header.
I want to make them to one file.So I found something similar to me. Link is Merge CSV files into a single file with no repeated headers.
but I want to return the data as a String, but this code has no return.
I try to modify that. but I failed.
I want to put the data from several csv into one variable.
String[] headers = null;
String firstFile = "/path/to/firstFile.dat";
Scanner scanner = new Scanner(new File(firstFile));
if (scanner.hasNextLine())
headers[] = scanner.nextLine().split(",");
scanner.close();
Iterator<File> iterFiles = listOfFilesToBeMerged.iterator();
BufferedWriter writer = new BufferedWriter(new FileWriter(firstFile, true));
while (iterFiles.hasNext()) {
File nextFile = iterFiles.next();
BufferedReader reader = new BufferedReader(new FileReader(nextFile));
String line = null;
String[] firstLine = null;
if ((line = reader.readLine()) != null)
firstLine = line.split(",");
if (!Arrays.equals (headers, firstLine))
throw new FileMergeException("Header mis-match between CSV files: '" +
firstFile + "' and '" + nextFile.getAbsolutePath());
while ((line = reader.readLine()) != null) {
writer.write(line);
writer.newLine();
}
reader.close();
}
writer.close();
Here is what you might be looking for.
I have read two csv files and written into one.
Hope this is use full...
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
public class CombineTwoFile
{
public static void main(String[] args) throws IOException
{
ArrayList<String> list = new ArrayList<String>();
try
{
BufferedReader br = new BufferedReader(new FileReader( "d:\\1\\1.csv"));
BufferedReader r = new BufferedReader(new FileReader( "d:\\1\\2.csv"));
String s1 =null;
String s2 = null;
while ((s1 = br.readLine()) != null)
{
list.add(s1);
}
while((s2 = r.readLine()) != null)
{
list.add(s2);
}
}
catch (IOException e)
{
e.printStackTrace();
}
BufferedWriter writer=null;
writer = new BufferedWriter(new FileWriter("d:\\1\\good.csv"));
String listWord;
for (int i = 0; i< list.size(); i++)
{
listWord = list.get(i);
writer.write(listWord);
writer.write("\n");
}
System.out.println("DONE Enjoy!!");
writer.close();
}
}
Or if you looking for a function which returns String combining two csv
public static String combineCSV() {
ArrayList<String> list = new ArrayList<String>();
try {
BufferedReader br = new BufferedReader(new FileReader(
"d:\\1\\1.csv"));
BufferedReader r = new BufferedReader(
new FileReader("d:\\1\\2.csv"));
String s1 = null;
String s2 = null;
while ((s1 = br.readLine()) != null) {
list.add(s1);
}
while ((s2 = r.readLine()) != null) {
list.add(s2);
}
} catch (IOException e) {
e.printStackTrace();
}
String listWord;
StringBuffer objBuffer = new StringBuffer();
for (int i = 0; i < list.size(); i++) {
listWord = list.get(i);
objBuffer.append(listWord);
objBuffer.append("\n");
}
System.out.println("DONE Enjoy!!");
System.out.println(objBuffer);
return objBuffer.toString();
}
Thank you!!!!
Enjoy Coding...
Another alternative is to use Open CSV library
I'm trying to read data from a text file and create Item Objects with it.
Item Objects have fields String title, String formatt, boolean onLoan, String loanedTo and String dateLoaned. In my save()method, I print every object to a text file in a new line and the fields are seperated by "$" (dollar sign). How can I read the text file line by line and create a new object from each line and add it to an array.
TextFile Example:
StarWars$DVD$false$null$null
Aliens$Bluray$true$John$Monday
public void save() {
String[] array2 = listForSave();
PrintWriter printer = null;
try {
printer = new PrintWriter(file);
for (String o : array2) {
printer.println(o);
}
printer.close();
} catch ( IOException e ) {
e.printStackTrace();
}
}
public void open(){
try{
FileReader fileReader = new FileReader(file);
BufferedReader bufferedReader = new BufferedReader(fileReader);
StringBuffer stringBuffer = new StringBuffer();
String line;
while ((line = bufferedReader.readLine()) != null) {
stringBuffer.append(line);
stringBuffer.append("\n");
}
fileReader.close();
System.out.println("Contents of file:");
System.out.println(stringBuffer.toString());
}catch ( IOException e ) {
e.printStackTrace();
}
}
Thanks everyone. Here's my final code:
public void open(){
try{
FileReader fileReader = new FileReader(file);
BufferedReader bufferedReader = new BufferedReader(fileReader);
String line;
String[] strings;
while ((line = bufferedReader.readLine()) != null) {
strings = line.split("\\$");
String title = strings[0];
String format = strings[1];
boolean onLoan = Boolean.parseBoolean(strings[2]);
String loanedTo = strings[3];
String dateLoaned = strings[4];
MediaItem superItem = new MediaItem(title,format, onLoan,loanedTo,dateLoaned);
items.add(superItem);
}
fileReader.close();
}catch ( IOException e ) {
e.printStackTrace();
}
}
String line = // input line e.g. "Aliens$Bluray$true$John$Monday"
String[] strings = line.split("\\$"); // use regex matching "$" to split
String title = strings[0];
String formatt = strings[1];
boolean onLoan = Boolean.parseBoolean(strings[2]);
String loanedTo = strings[3];
String dateLoaned = strings[4];
// TODO: create object from those values
Maybe you need to handle null differently (in case you want the String "null" to be converted to null); note that you can't distinguish if null or "null" was saved.
This function converts "null" to null and returns the same string otherwise:
String convert(String s) {
return s.equals("null") ? null : s;
}
Reading the objects to an array
Since you don't know the number of elements before reading all lines, you have to work around that:
Write the number of objects in the file as first line, which would allow you to create the array before reading the first object. (Use Integer.parseInt(String) to convert the first line to int):
public void save() {
String[] array2 = listForSave();
PrintWriter printer = null;
try {
printer = new PrintWriter(file);
printer.println(array2.length);
for (String o : array2) {
printer.println(o);
}
printer.close();
} catch ( IOException e ) {
e.printStackTrace();
}
}
public void open(){
try{
FileReader fileReader = new FileReader(file);
BufferedReader bufferedReader = new BufferedReader(fileReader);
StringBuffer stringBuffer = new StringBuffer();
int arraySize = Integer.parseInt(stringBuffer.readLine());
Object[] array = new Object[arraySize];
int index = 0;
String line;
while ((line = bufferedReader.readLine()) != null) {
// split line and create Object (see above)
Object o = // ...
array[index++] = o;
}
//...
}catch ( IOException e ) {
e.printStackTrace();
}
//...
}
or
Use a Collection, e.g. ArrayList to store the objects and use List.toArray(T[]) to get an array.
quick and dirty solution might be...
public void open(){
try{
ArrayList<Item> list = new ArrayList<Item>(); //Array of your ItemObject
FileReader fileReader = new FileReader(file);
BufferedReader bufferedReader = new BufferedReader(fileReader);
StringBuffer stringBuffer = new StringBuffer();
String line;
while ((line = bufferedReader.readLine()) != null) {
Item itm = new Item(); //New Item Object
String [] splitLine = line.split("\\$");
item.title = splitLine[0];
item.format = splitLine[1];
item.onLoan = Boolean.parseBoolean(splitLine[2]);
item.loanedTo = splitLine[3];
item.dateLoaned = splitLine[4];
list.add(itm);
stringBuffer.append(line);
stringBuffer.append("\n");
}
fileReader.close();
System.out.println("Contents of file:");
System.out.println(stringBuffer.toString());
}catch ( IOException e ) {
e.printStackTrace();
}
}
But this is won't scale if you need to re-arrange or add new fields.
You could try this to "parse" every line of your file
String[] result = "StarWars$DVD$false$null$null".split("\\$");
for (int i=0; i<result.length; i++) {
String field = result[i]
... put the strings in your object ...
}
I am parsing a file data on the base of \t what I want if found more then one \t start parsing from next new line and start arraylist words from 0.
public static void readFile() throws IOException {
String line;
ArrayList<String> words = new ArrayList<String>();
try {
BufferedReader inFile = new BufferedReader (new FileReader ("/weather.txt"));
while ((line = inFile.readLine()) != null) {
StringTokenizer token= new StringTokenizer(line,"\t");
while (token.hasMoreTokens()) {
words.add(token.nextToken());
}
/*
* function to print the values
*/
getMetadataTriple(words);
}
}
Try the following regex solution:
public static void readFile() throws IOException
{
String line;
ArrayList<String> words = new ArrayList<String>();
try
{
BufferedReader inFile = new BufferedReader(new FileReader("weather.txt"));
while ((line = inFile.readLine()) != null)
{
String[] temp = line.split("\\t");
for (String s : temp)
{
if(!s.isEmpty())
{
words.add(s);
}
else //another \t
{
words.clear();
break;
}
}
/*
* function to print the values
*/
getMetadataTriple(words);
}
}
catch (Exception e)
{
e.printStackTrace();
}
}