Here's the code:
FileReader fr = new FileReader("datos_clientes.txt");
BufferedReader br = new BufferedReader(fr);
while ((line = br.readLine()) != null) {
String nameMark = "#n";
String addressMark = "#d";
int nameStart = line.indexOf(nameMark) + nameMark.length();
int addressStart = line.indexOf(addressMark) + addressMark.length();
String name = line.substring(nameStart, addressStart - addressMark.length());
String address = line.substring(addressStart, line.length());
if (line.startsWith("tipo1.")) {
FileWriter fw = new FileWriter(name +".txt");
char[] vector = name.toCharArray();
char[] vector2 = address.toCharArray();
int index = 0;
while (index < vector.length) {
fw.write(vector[index]+vector2[index]);
index++;
}
fw.close();
} else if (line.startsWith("tipo2.")) {
FileWriter fw = new FileWriter(name +".txt");
char[] vector = name.toCharArray();
char[] vector2 = address.toCharArray();
int index = 0;
while (index < vector.length) {
fw.write(vector[index]+vector2[index]);
index++;
}
fw.close();
}
else if (line.startsWith("tipo3.")) {
FileWriter fw = new FileWriter(name +".txt");
char[] vector = name.toCharArray();
char[] vector2 = address.toCharArray();
int index = 0;
while (index < vector.length) {
fw.write(vector[index]+vector2[index]);
index++;
}
fw.close();
}
}
What I want from this code is to create the each new file with the name of the recipient and their address.
The new files just show a combination of random alphabethical characters.
Then I have three pre-made files which I have to include in each new file so for example if one of the new files is "Maria Roberts.txt" and this person will receive a "type 1" letter I want the file (Maria Roberts.txt) to include the name, her address and the file "type1.txt"
I don't know how to do that.
I know I add things in every new question... sorry, I thing it will be easier for me to understand it.
Thanks again!
You're adding one character from the name array with one character from the address array, then outputting the result.
fw.write(vector[index]+vector2[index]);
Instead, you want to write the entire name array, then (in a different loop) write the entire address array.
int index = 0;
while (index < vector.length) {
fw.write(vector[index]);
index++;
}
index = 0;
while (index < vector2.length) {
fw.write(vector2[index]);
index++;
}
That will just stick them together, but you can use your imagination and figure out how to separate them the way you want.
Related
This is some code that I found to help with reading in a 2D Array, but the problem I am having is this will only work when reading a list of number structured like:
73
56
30
75
80
ect..
What I want is to be able to read multiple lines that are structured like this:
1,0,1,1,0,1,0,1,0,1
1,0,0,1,0,0,0,1,0,1
1,1,0,1,0,1,0,1,1,1
I just want to essentially import each line as an array, while structuring them like an array in the text file.
Everything I have read says to use scan.usedelimiter(","); but everywhere I try to use it the program throws straight to the catch that replies "Error converting number". If anyone can help I would greatly appreciate it. I also saw some information about using split for the buffered reader, but I don't know which would be better to use/why/how.
String filename = "res/test.txt"; // Finds the file you want to test.
try{
FileReader ConnectionToFile = new FileReader(filename);
BufferedReader read = new BufferedReader(ConnectionToFile);
Scanner scan = new Scanner(read);
int[][] Spaces = new int[10][10];
int counter = 0;
try{
while(scan.hasNext() && counter < 10)
{
for(int i = 0; i < 10; i++)
{
counter = counter + 1;
for(int m = 0; m < 10; m++)
{
Spaces[i][m] = scan.nextInt();
}
}
}
for(int i = 0; i < 10; i++)
{
//Prints out Arrays to the Console, (not needed in final)
System.out.println("Array" + (i + 1) + " is: " + Spaces[i][0] + ", " + Spaces[i][1] + ", " + Spaces[i][2] + ", " + Spaces[i][3] + ", " + Spaces[i][4] + ", " + Spaces[i][5] + ", " + Spaces[i][6]+ ", " + Spaces[i][7]+ ", " + Spaces[i][8]+ ", " + Spaces[i][9]);
}
}
catch(InputMismatchException e)
{
System.out.println("Error converting number");
}
scan.close();
read.close();
}
catch (IOException e)
{
System.out.println("IO-Error open/close of file" + filename);
}
}
I provide my code here.
public static int[][] readArray(String path) throws IOException {
//1,0,1,1,0,1,0,1,0,1
int[][] result = new int[3][10];
BufferedReader reader = new BufferedReader(new FileReader(path));
String line = null;
Scanner scanner = null;
line = reader.readLine();
if(line == null) {
return result;
}
String pattern = createPattern(line);
int lineNumber = 0;
MatchResult temp = null;
while(line != null) {
scanner = new Scanner(line);
scanner.findInLine(pattern);
temp = scanner.match();
int count = temp.groupCount();
for(int i=1;i<=count;i++) {
result[lineNumber][i-1] = Integer.parseInt(temp.group(i));
}
lineNumber++;
scanner.close();
line = reader.readLine();
}
return result;
}
public static String createPattern(String line) {
char[] chars = line.toCharArray();
StringBuilder pattern = new StringBuilder();;
for(char c : chars) {
if(',' == c) {
pattern.append(',');
} else {
pattern.append("(\\d+)");
}
}
return pattern.toString();
}
The following piece of code snippet might be helpful. The basic idea is to read each line and parse out CSV. Please be advised that CSV parsing is generally hard and mostly requires specialized library (such as CSVReader). However, the issue in hand is relatively straightforward.
try {
String line = "";
int rowNumber = 0;
while(scan.hasNextLine()) {
line = scan.nextLine();
String[] elements = line.split(',');
int elementCount = 0;
for(String element : elements) {
int elementValue = Integer.parseInt(element);
spaces[rowNumber][elementCount] = elementValue;
elementCount++;
}
rowNumber++;
}
} // you know what goes afterwards
Since it is a file which is read line by line, read each line using a delimiter ",".
So Here you just create a new scanner object passing each line using delimter ","
Code looks like this, in first for loop
for(int i = 0; i < 10; i++)
{
Scanner newScan=new Scanner(scan.nextLine()).useDelimiter(",");
counter = counter + 1;
for(int m = 0; m < 10; m++)
{
Spaces[i][m] = newScan.nextInt();
}
}
Use the useDelimiter method in Scanner to set the delimiter to "," instead of the default space character.
As per the sample input given, if the next row in a 2D array begins in a new line, instead of using a ",", multiple delimiters have to be specified.
Example:
scan.useDelimiter(",|\\r\\n");
This sets the delimiter to both "," and carriage return + new line characters.
Why use a scanner for a file? You already have a BufferedReader:
FileReader fileReader = new FileReader(filename);
BufferedReader reader = new BufferedReader(fileReader);
Now you can read the file line by line. The tricky bit is you want an array of int
int[][] spaces = new int[10][10];
String line = null;
int row = 0;
while ((line = reader.readLine()) != null)
{
String[] array = line.split(",");
for (int i = 0; i < array.length; i++)
{
spaces[row][i] = Integer.parseInt(array[i]);
}
row++;
}
The other approach is using a Scanner for the individual lines:
while ((line = reader.readLine()) != null)
{
Scanner s = new Scanner(line).useDelimiter(',');
int col = 0;
while (s.hasNextInt())
{
spaces[row][col] = s.nextInt();
col++;
}
row++;
}
The other thing worth noting is that you're using an int[10][10]; this requires you to know the length of the file in advance. A List<int[]> would remove this requirement.
I have a .txt file that contains text that I would like to save part of it in a String, part of it in a String array, and then the last part in a 2D int array, and am faced with two issues:
How to read and save both of the arrays when their size is not known ahead of time?
2D array is not reading/saving properly
Here is the text file for reference:
This is the sentence to be read.
This
is
a
String
array.
90 47 110 95 95
101 87
54 0 38 12
Here is part of my method that is supposed to read and save the three data types:
BufferedReader br = new BufferedReader(new FileReader(fileName));
sentence = br.readLine();
stringArr = new String[5]; //how to initialize without set number of elements?
for(int i = 0; i<stringArr.length; i++){
stringArr[i] = br.readLine();
}
int2DArr = new int[3][5]; //how to initialize with any amount of rows and columns?
for(int i = 0; i<int2DArr.length; i++){
for(int j = 0; j<int2DArr[i].length; j++){
int2DArr[i][j] = br.read();
//how to read the space after each int ?
}
}
How would I "grab" the size of the arrays by reading the text file, so that when I initialize both arrays, I have the proper sizes? Any help would be greatly appreciated!
Instead of trying to achieve everything in a single pass we can pass through the file twice and obtain a neater code.
It will consume double time of course but it is going to help you understand how you could break bigger problems into smaller ones and deal with them one by one.
Here are the steps:
Determine size of stringArr and intArr in first pass
Fill value in respective array in second pass
If you are wondering how no of columns for int2DArr is determine. Simply we don't do it our self. We use the concept of Jagged Arrays
Read more here How do I create a jagged 2d array in Java?
import java.util.*;
import java.io.*;
class ReadFileIntoArr {
public static void main(String args[]) throws IOException {
String fileName = "test.txt";
BufferedReader br = new BufferedReader(new FileReader(fileName));
String line = br.readLine();
int strSize = 0;
int intSize = 0;
boolean isDigit = false;
while (line != null && line.trim().length() != 0) {
if (!isDigit && Character.isDigit(line.charAt(0)))
isDigit = true;
if (isDigit)
intSize++;
else
strSize++;
line = br.readLine();
}
br = new BufferedReader(new FileReader(fileName));
String[] stringArr = new String[strSize];
for (int i = 0; i < stringArr.length; i++)
stringArr[i] = br.readLine();
int[][] int2DArr = new int[intSize][];
for (int i = 0; i < int2DArr.length; i++)
int2DArr[i] = Arrays.stream(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray();
System.out.println(Arrays.toString(stringArr));
System.out.println(Arrays.deepToString(int2DArr));
}
}
Note: In single pass this could be accomplished with the help of ArrayList and later transfer everything into respective array.
Update: After understanding the constraints for your problem here is another version
import java.util.*;
import java.io.*;
class ReadFileIntoArr {
public static void main(String args[]) throws IOException {
String fileName = "test.txt";
BufferedReader br = new BufferedReader(new FileReader(fileName));
String line = br.readLine();
int strSize = 0;
int intSize = 0;
boolean isDigit = false;
while (line != null && line.trim().length() != 0) {
if (!isDigit && isDigit(line.charAt(0)))
isDigit = true;
if (isDigit)
intSize++;
else
strSize++;
line = br.readLine();
}
br = new BufferedReader(new FileReader(fileName));
String[] stringArr = new String[strSize];
for (int i = 0; i < stringArr.length; i++)
stringArr[i] = br.readLine();
int[][] int2DArr = new int[intSize][];
for (int i = 0; i < int2DArr.length; i++)
int2DArr[i] = convertStringArrToIntArr(br.readLine().split(" "));
System.out.println(Arrays.toString(stringArr));
System.out.println(Arrays.deepToString(int2DArr));
}
public static boolean isDigit(char c) {
return c >= '0' && c <= '9';
}
public static int[] convertStringArrToIntArr(String[] strArr) {
int[] intArr = new int[strArr.length];
for (int i = 0; i < strArr.length; i++)
intArr[i] = Integer.parseInt(strArr[i]);
return intArr;
}
}
Path path = Paths.get(fileName);
List<String> lines = Files.readAllLines(path, Charset.defaultCharset());
String title = lines.get(0);
List<String> words = new ArrayList<>();
for (int i = 1; i < lines.size(); ++i) {
String word = lines.get(i);
if (!word.isEmpty() && Character.isDigit(word.codePointAt(0)) {
break;
}
words.add(word);
}
String[] wordArray = words.toArray(new String[]);
int i0 = 1 + words.size();
int n = lines.size() - i0;
int[][] numbers = new int[n][];
for (int i = i0; i < lines.size(); ++i) {
String[] values = lines.get(i).trim().split("\\s+");
int m = values.length;
int[] row = new int[m];
for (int j = 0; j < m; ++m) {
row[j] = Integer.parse(values[j]);
}
numbers[i - i0] = row;
}
Path is a generalisation of File, also URLs.
Files is a treasure trove of file functions.
One could do without dynamically sized List; one would need to test first,
but normally one would use a List anyhow.
String.split splits on one or more whitespace.
I have 6 columns in one table and one of the column contains Chinese character and I have 200 records in that table.
I have written the code to save it one text file. The problem is while fetching all records, I am able to see the chinese text in the file. But while fetching only one record I am seeing the Chinese text is garbled.
I am using the below code.
public static void main(String args[]){
String outputFile = fileNameEncode("C:\\a\a.txt");
FileOutputStream os = new FileOutputStream(outputFile);
writeToFile(os);
}
private static String fileNameEncode(String name) {
String file;
try {
byte[] utf_byte = name.getBytes("UTF-8");
StringBuilder sb = new StringBuilder(1024);
for (byte b : utf_byte) {
int integer = b & 0xFF; // drop the minus sign
sb.append((char) integer);
}
file = sb.toString();
} catch (Exception e) {
file = name;
}
return file;
}
public void writeToFile(FileOutputStream os) {
PrintWriter pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(ostream, "GBK")));
for (int rowNum = 0; rowNum < arrayList.size(); rowNum++) {//arrayList contains data from db
ArrayList list = arrayList.get(rowNum);
for(int k = 0; k < list.size(); k++{
String[] data = new String[6];
for (int colNum = 0; colNum < 6; colNum++) {
data[colNum] = list.get(i).toString();
}
String outLine = composeLine(data, ctlInfo);
// write the line
pw.print(outLine);
pw.println();
}
}
}
private static String composeLine(String[] data, ControlInfo ctl) {
StringBuilder line = new StringBuilder();
String delim = ","
int elemCount = data.length;
for (int i = 0; i < elemCount; i++) {
if (i > 0)
line.append(delim);
if (data[i] != null && (data[i].contains("\n") || data[i].contains("\r") ||
data[i].contains("\r\n"))){
data[i] = data[i].replaceAll("(\\t|\\r?\\n)+", " ");
}
else {
line.append(data[i]);
}
}
return line.toString();
}
could you please let me know where I am wrong?
I found the issue, the code is good, the problem is in notepad++. If the character set in node pad ++ is Chinese(GB2312) then I am able to see the correct text. The note pad ++ is auto set GB2312 for two lines but for one line it is not doing auto set to GB2312.
I'm trying to code a program that given a file with the names and addresses of five or more people, creates one different file (letter) for each of them (the new files will be named as the person who will receive it).
The structure of the main file is something like this:
type1.0001 #n John Harrison #a Whatever Street, 490 - Liverpool
.... and so on
So "type1" is the type of letter this person has to be sent, the words after "#n" are the name, and the words after "#a" the address.
What I've been trying is this:
String datos = "main_file.txt";
String tipo1 = "type1.txt";
String tipo2 = "type2.txt";
String tipo3 = "type3.txt";
char[] type1 = {'t', 'i', 'p', 'o', '1'};
//all other types should be here
String line;
FileReader fr = new FileReader("mainfile.txt");
BufferedReader br = new BufferedReader(fr);
while ((line = br.readLine()) != null) {
while ((line = br.readLine()) != ".") {
char[] lineArray = line.toCharArray();
if (lineArray == type1) {
//code that creates file type1
}
}
}
fr.close();
So far this would just be the code that decides which letter to send, but it doesn't work.
I think it's something related to the "while" loop.
Please, I started Java 1 month ago, so if anyone could help me I'd be so grateful!
Thanks
Right now, I've got this:
FileReader fr = new FileReader("main_file.txt");
BufferedReader br = new BufferedReader(fr);
while ((line = br.readLine()) != null) {
String nameMark = "#n";
String addressMark = "#a";
int nameStart = line.indexOf(nameMark) + nameMark.length();
int addressStart = line.indexOf(addressMark) + addressMark.length();
String name = line.substring(nameStart, addressStart - addressMark.length());
String address = line.substring(addressStart, line.length());
if (line.startsWith("tipo1.")) {
FileWriter fw = new FileWriter("file1.txt");
char[] vector = name.toCharArray();
int index = 0;
while (index < vector.length) {
fw.write(vector[index]);
index++;
}
fw.close();
} else if (line.startsWith("tipo2.")) {
FileWriter fw = new FileWriter("file1.txt");
char[] vector = name.toCharArray();
int index = 0;
while (index < vector.length) {
fw.write(vector[index]);
index++;
}
fw.close();
}
}
fr.close();
But it doesn't work.
Can someone help me out?
As Marc B told you, don't read the lines twice.
Also, just comparing the start of the line, will be much less overkill than you char array stuff.
To retrieve name and address, you could use indexOf and substring methods of String.
Here is a whole example :
while ((line = br.readLine()) != null) {
// get the name and the address of this line
String nameMark = "#n";
String addressMark = "#a";
int nameStart = line.indexOf(nameMark) + nameMark.length();
int addressStart = line.indexOf(addressMark) + addressMark.length();
String name = line.substring(nameStart, addressStart - addressMark.length());
String address = line.substring(addressStart, line.length());
// get the line type
if (line.startsWith("tipo1")) {
//code that creates file type1 with name and address
}
else if(line.startsWith("tipo2")) {
//code that creates file type2 with name and address
}
...
...
}
You can't use == with arrays. (Well, you can, but it doesn't do what you expect.) That is, this line is wrong:
if (lineArray == type1)
Try Arrays.equals instead:
if (Arrays.equals(lineArray, type1))
Try this for starters.
String line;
FileReader fr = new FileReader("mainfile.txt");
BufferedReader br = new BufferedReader(fr);
while ((line = br.readLine()) != null) { // finish when line is null not "."
String [] parts = line.split("#");
String name, address;
if (parts.length > 2) {
name = parts[1].substring(2);
address = parts[2].substring(2);
}
if (line.startsWith("tipo1")) {
// save to tipo1 file
} else if (line.startsWith("tipo2")) {
// save to tipo2 file
} else if (line.startsWith("tipo2")) {
// save to tipo2 file
} else if (line.startsWith("tipo3")) {
// save to tipo2 file
} else if (line.startsWith("tipo4")) {
// save to tipo2 file
} else if (line.startsWith("tipo2")) {
// save to tipo2 file
}
}
fr.close();
I want to transform a csv file. My file looks like that:
I am using the opencsv libary to parse my csv. That is my run method to parse the file:
public void run() throws Exception {
CSVReader reader = new CSVReader(new FileReader(csvFile), ';');
String [] nextLine;
int i = -1;
String fileName = "";
String companyName = "";
String currency = "";
String writerPath;
List<String> returnList = null;
List<String> dateList = null;
while ((nextLine = reader.readNext()) != null && i < 10) {
String[] line = nextLine;
System.out.println(line[0]);
System.out.println(line);
i++;
//fileName of the String
if(!line[0].contains("NULL")) {
fileName = line[0];
}
writerPath = "C:\\Users\\Desktop\\CSVOutput\\" + fileName + ".csv";
//write csv file
CSVWriter writer = new CSVWriter(new FileWriter(writerPath), ';');
//write Header
String[] entries = "Name;Date;TotalReturn;Currency".split(";");
writer.writeNext(entries);
//create Content
//companyName of the String
if(!line[1].contains("Name")) {
companyName = line[1];
System.out.println(companyName);
}
//currency
if(!line[2].contains("CURRENCY")) {
currency = line[2];
}
//total returns
returnList = new ArrayList<String>();
if(line[0].contains("NULL")) {
for(int j = 3; j <= line.length; j++) {
returnList.add(line[j]); // EXCPETION COMES HERE!
}
}
//"Name;Date;TotalReturn;Currency"
List<String[]> data = new ArrayList<String[]>();
for(int m = 0; m <= line.length; m++) {
data.add(new String[] {companyName, "lolo", "hereComesTheDateLater", currency});
}
writer.writeAll(data);
//close Writer
writer.close();
}
System.out.println("Done");
}
}
I am getting an
java.lang.ArrayIndexOutOfBoundsException: 3039
at com.TransformCSV.main.ParseCSV.run(ParseCSV.java:78)
at com.TransformCSV.main.ParseCSV.main(ParseCSV.java:20)
at this line: returnList.add(line[j]);?
Why? What are possible ways to fix that?
I really appreciate your answer!
You want j < line.length and not <=. If there are 10 elements in an Array then there is not an item at index 10 - you only have 0-9.
Further using loads of variables and assigning them is not the preferred way to parse CSV. Java is an Object Orientated language.
Use an Object to represent each line and bind the line using the opencsv javabean API
You are parsing the file till length of file <= instead you have to use <. It will access the file till line.length - 1
Replace with this
for(int j = 3; j <line.length; j++) {
returnList.add(line[j]);
}