Develop Reference

Search for multiline String in a text file

I have a text file from which i am trying to search for a String which has multiple lines. A single string i am able to search but i need multi line string to be searched.
I have tried to search for single line which is working fine.
public static void main(String[] args) throws IOException
{
File f1=new File("D:\\Test\\test.txt");
String[] words=null;
FileReader fr = new FileReader(f1);
BufferedReader br = new BufferedReader(fr);
String s;
String input="line one";
// here i want to search for multilines as single string like
// String input ="line one"+
// "line two";
int count=0;
while((s=br.readLine())!=null)
{
words=s.split("\n");
for (String word : words)
{
if (word.equals(input))
{
count++;
}
}
}
if(count!=0)
{
System.out.println("The given String "+input+ " is present for "+count+ " times ");
}
else
{
System.out.println("The given word is not present in the file");
}
fr.close();
}
And below are the file contents.
line one
line two
line three
line four

Use the StringBuilder for that, read every line from file and append them to StringBuilder with lineSeparator
StringBuilder lineInFile = new StringBuilder();
while((s=br.readLine()) != null){
lineInFile.append(s).append(System.lineSeparator());
}
Now check the searchString in lineInFile by using contains
StringBuilder searchString = new StringBuilder();
builder1.append("line one");
builder1.append(System.lineSeparator());
builder1.append("line two");
System.out.println(lineInFile.toString().contains(searchString));

More complicated solution from default C (code is based on code from book «The C programming language» )
final String searchFor = "Ich reiß der Puppe den Kopf ab\n" +
"Ja, ich reiß' ich der Puppe den Kopf ab";
int found = 0;
try {
String fileContent = new String(Files.readAllBytes(
new File("puppe-text").toPath()
));
int i, j, k;
for (i = 0; i < fileContent.length(); i++) {
for (k = i, j = 0; (fileContent.charAt(k++) == searchFor.charAt(j++)) && (j < searchFor.length());) {
// nothig
}
if (j == searchFor.length()) {
++found;
}
}
} catch (IOException ignore) {}
System.out.println(found);

Why don't you just normalize all the lines in the file to one string variable and then just count the number of occurrences of the input in the file. I have used Regex to count the occurrences but can be done in any custom way you find suitable.
public static void main(String[] args) throws IOException
{
File f1=new File("test.txt");
String[] words=null;
FileReader fr = new FileReader(f1);
BufferedReader br = new BufferedReader(fr);
String s;
String input="line one line two";
// here i want to search for multilines as single string like
// String input ="line one"+
// "line two";
int count=0;
String fileStr = "";
while((s=br.readLine())!=null)
{
// Normalizing the whole file to be stored in one single variable
fileStr += s + " ";
}
// Now count the occurences
Pattern p = Pattern.compile(input);
Matcher m = p.matcher(fileStr);
while (m.find()) {
count++;
}
System.out.println(count);
fr.close();
}
Use StringBuilder class for efficient string concatenation.

Try with Scanner.findWithinHorizon()
String pathToFile = "/home/user/lines.txt";
String s1 = "line two";
String s2 = "line three";
String pattern = String.join(System.lineSeparator(), s1, s2);
int count = 0;
try (Scanner scanner = new Scanner(new FileInputStream(pathToFile))) {
while (scanner.hasNext()) {
String withinHorizon = scanner.findWithinHorizon(pattern, pattern.length());
if (withinHorizon != null) {
count++;
} else {
scanner.nextLine();
}
}
} catch (FileNotFoundException e) {
e.printStackTrace();
}
System.out.println(count);

Try This,
public static void main(String[] args) throws IOException {
File f1 = new File("./src/test/test.txt");
FileReader fr = new FileReader(f1);
BufferedReader br = new BufferedReader(fr);
String input = "line one";
int count = 0;
String line;
while ((line = br.readLine()) != null) {
if (line.contains(input)) {
count++;
}
}
if (count != 0) {
System.out.println("The given String " + input + " is present for " + count + " times ");
} else {
System.out.println("The given word is not present in the file");
}
fr.close();
}

How to trim last 4 characters of each elements present in an arraylist in java?

I have imported a set of values into an array list from a csv file. Now i need to remove the extension .tar from each element or allow only first 8 characters to be inserted into the array list while importing it from a csv file. This is my code and i want that change in array1 part
import java.io.*;
import java.util.*;
import java.util.ArrayList;
import java.lang.*;
public class compare
{
public static void main(String[] args)
{
ArrayList<String> array = new ArrayList<String>(); //Array for storing values
ArrayList<String> array1 = new ArrayList<String>(); //Array for storing values
try
{
String strFile = "D:\\Ramakanth\\PT2573\\ftp.csv"; //csv file containing data
BufferedReader br = new BufferedReader( new FileReader(strFile)); //create BufferedReader to
String strLine = "";
StringTokenizer st = null;
while( (strLine = br.readLine()) != null) //read comma separated file line by line
{
st = new StringTokenizer(strLine, ","); //break comma separated line using ","
while(st.hasMoreTokens())
{
array.add(st.nextToken()); //store csv values in array
}
}
}
catch(Exception e)
{
System.out.println("Exception while reading csv file: " + e);
}
try
{
String strFile1 = "D:\\Ramakanth\\PT2573\\target.csv"; //csv file containing data
BufferedReader br1 = new BufferedReader( new FileReader(strFile1)); //create BufferedReader
String strLine1 = "";
StringTokenizer st1 = null;
while( (strLine1 = br1.readLine()) != null) //read comma separated file line by line
{
st1 = new StringTokenizer(strLine1, ","); //break comma separated line using ","
while(st1.hasMoreTokens())
{
array1.add(st1.nextToken()); //store csv values in array
}
}
}
catch(Exception e)
{
System.out.println("Exception while reading csv file: " + e);
}
array.removeAll(array1);
System.out.println(array);
try
{
BufferedWriter br2 = new BufferedWriter(new FileWriter("D:\\Ramakanth\\PT2573\\output.csv"));
StringBuilder sb1 = new StringBuilder();
for (String element : array)
{
sb1.append(element);
sb1.append(" ");
}
br2.write(sb1.toString());
br2.close();
}
catch(Exception e)
{
System.out.println("Exception while writing csv file: " + e);
}
}
}

Try this,
String element = "extension.tar";
int index = element.lastIndexOf(".");
System.out.println("if Dot extension means : " + element.substring(0, index));
element = element.substring(0, 8);
System.out.println("if first 8 character means : " + element);
output:
if Dot extension means : extension
if first 8 character means : extensio

You can do by using StringUtils.substringBefore class by using
StringUtils.substringBefore(yourstring, ".tar" );
It will give you the desired output

Java Code check fields in duplicate, when value change start again

I want to write small java program to read data file first field and add seqcution number
Input file:
robert,190 vikign,...
robert,2401 windy,...
robert,1555 oakbrook,...
michell,2524 sprint,...
michell,1245 oakbrrok,...
xyz,2455 xyz drive,....
Output file should be:
robert,190 vikign,...,0
robert,2401 windy,...,1
robert,1555 oakbrook,...,2
michell,2524 sprint,...,0
michell,1245 oakbrrok,...,1
xyz,2455 xyz drive,....,0
Check first field when value change sequction number start back to 0 otherwise add sequction number by 1
here is my code:
public static void createseq(String str) {
try {
BufferedReader br = null;
BufferedWriter bfAllBWP = null;
File folderall = new File("Sort_Data_File_Out");
File[] BFFileall = folderall.listFiles();
for (File file : BFFileall) {
br = new BufferedReader(new FileReader(file));
String bwp = "FinalDataFileOut\\" + str;
bfAllBWP = new BufferedWriter(new FileWriter(bwp));
String line;
line = br.readLine();
String[] actionID = line.split("\\|");
String fullname = actionID[0].trim();
int seq = 0;
String fullnameb;
while ((line = br.readLine()) != null) {
actionID = line.split("\\|");
fullnameb = actionID[0].trim();
if(fullname.equals(fullnameb)) {
seq++;
}
else {
System.out.println(line + "======" + seq + "\n");
seq = 0;
fullname = fullnameb;
}
System.out.println("dshgfsdj "+line + "======" + seq + "\n");
}
}
}
catch(Exception letterproof) {
letterproof.printStackTrace();
}
}

The below code will fix the issue.I have updated the code if you face any pblm plz let me know :
Input :
robert,190 vikign,...
robert,2401 windy,...
robert,1555 oakbrook,...
michell,2524 sprint,...
michell,1245 oakbrrok,...
xyz,2455 xyz drive,....
Code :
public static void createseq() {
try {
File file = new File("d:\\words.txt"); //Hardcoded file for testing locally
BufferedReader br = new BufferedReader(new FileReader(file));
HashMap<String,Integer> counter = new HashMap<String, Integer>();
String line;
while((line = br.readLine())!= null)
{
String[] actionID = line.split(",");
String firstName = actionID[0];
if(counter.containsKey(firstName))
{
counter.put(firstName, counter.get(firstName) + 1);
}
else
{
counter.put(firstName,0);
}
System.out.println(line+" "+counter.get(firstName));
}
br.close();
} catch(Exception letterproof) {
letterproof.printStackTrace();
}
}
Ouput Come :
robert,190 vikign,... 0
robert,2401 windy,... 1
robert,1555 oakbrook,... 2
michell,2524 sprint,... 0
michell,1245 oakbrrok,... 1
xyz,2455 xyz drive,.... 0

Count the amount of times a string appears in a file

I'm trying to figure out how I would read a file, and then count the amount of times a certain string appears.
This is what my file looks like, it's a .txt:
Test
Test
Test
Test
I want the method to then return how many times it is in the file. Any idea's on how I could go about doing this? I mainly need help with the first part. So if I was searching for the string "Test" I would want it to return 4.
Thanks in advanced! Hope I gave enough info!

Add this method to your class, pass your FileInputStream to it, and it should return the number of words in a file. Keep in mind, this is case sensitive.
public int countWord(String word, FileInputStream fis) {
BufferedReader in = new BufferedReader(new InputStreamReader(fis));
String readLine = "";
int count = 0;
while((readLine = in.readLine()) != null) {
String words = readLine.split(" ");
for(String s : words) {
if(s.equals(word)) count++;
}
return count;
}
Just wrote that now, and it's untested, so let me know if it works. Also, make sure that you understand what I did if this is a homework question.

Here you are:
public int countStringInFile(String stringToLookFor, String fileName){
int count = 0;
try{
FileInputStream fstream = new FileInputStream(fileName);
DataInputStream in = new DataInputStream(fstream);
BufferedReader br = new BufferedReader(new InputStreamReader(in));
String strLine;
while ((strLine = br.readLine()) != null) {
int startIndex = strLine.indexOf(stringToLookFor);
while (startIndex != -1) {
count++;
startIndex = base.indexOf(stringToLookFor,
startIndex +stringToLookFor.length());
}
}
in.close();
}catch (Exception e){//Catch exception if any
System.err.println("Error: " + e.getMessage());
}
return count;
}
Usage: int count = countStringInFile("SomeWordToLookFor", "FileName");

If you have got to the point of reading in each file into a string I would suggest looking at the String method split.
Give it the string code 'Test' and it will return an array of type string - count the number of elements per line. Sum them up to get your total occurrence.
import java.io.*;
public class StringCount {
public static void main(String args[]) throws Exception{
String testString = "Test";
String filePath = "Test.txt";
String strLine;
int numRead=0;
try {
FileInputStream fstream = new FileInputStream(filePath);
DataInputStream in = new DataInputStream(fstream);
BufferedReader br = new BufferedReader(new InputStreamReader(in));
while ((strLine = br.readLine()) != null) {
strLine = strLine + " ";
String [] strArry = strLine.split(testString);
if (strArry.length > 1) {
numRead = numRead + strArry.length - 1;
}
else {
if (strLine == testString) {
numRead++;
}
}
}
in.close();
System.out.println(testString + " was found " + numRead + " times.");
}catch (Exception e){
}
}
}

I would do this:
open and read the file line by line,
check how oft a line contains the given word...
increase a global counter for that..
public static void main(String[] args) throws IOException {
BufferedReader in = new BufferedReader(new FileReader("Test.txt"));
Scanner sc = new Scanner(System.in);
System.out.print("Enter the subtring to look for: ");
String word = sc.next();
String line = in.readLine();
int count = 0;
do {
count += (line.length() - line.replace(word, "").length()) / word.length();
line = in.readLine();
} while (line != null);
System.out.print("There are " + count + " occurrences of " + word + " in ");
}

skip inserting first line of csv file

I have a method that takes data from a .csv file and puts it into an array backwards
(first row goes in last array slot) however I would like the first row in the .csv file to not be in the array. How would I accomplish this? Here is my code thus far:
public static String[][] parse(String symbol) throws Exception{
String destination = "C:/"+symbol+"_table.csv";
LineNumberReader lnr = new LineNumberReader(new FileReader(new File(destination)));
lnr.skip(Long.MAX_VALUE);
String[][] stock_array = new String[lnr.getLineNumber()][3];
try{
BufferedReader br = new BufferedReader(new FileReader(destination));
String strLine = "";
StringTokenizer st = null;
int line = lnr.getLineNumber()-1;
while((strLine = br.readLine()) != null){
st = new StringTokenizer(strLine, ",");
while(st.hasMoreTokens()){
stock_array[line][0] = st.nextToken();
st.nextToken();
stock_array[line][1] = st.nextToken();
stock_array[line][2] = st.nextToken();
st.nextToken();
st.nextToken();
st.nextToken();
}
line--;
}
}
catch(Exception e){
System.out.println("Error while reading csv file: " + e);
}
return stock_array;
}

You can skip the first line by just reading it in and doing nothing. Do this just before your while loop:
br.readLine();
To make sure that your array is the right size and lines get stored in the right places, you should also make these changes:
String[][] stock_array = new String[lnr.getLineNumber()-1][3];
...
int line = lnr.getLineNumber()-2;

Your code is not efficient, as far as my knowledge goes. Also, you are using linenumberreader.skip(long.max_value), which is not a correct/confirmed way to find the line count of the file. StringTokenizer is kind of deprecated way of splitting tokens. I would code it, in the following way:
public static List<String[]> parse(String symbol) throws Exception {
String destination = "C:/"+symbol+"_table.csv";
List<String[]> lines = new ArrayList<String[]>();
try{
BufferedReader br = new BufferedReader(new FileReader(destination));
int index = 0;
while((line = br.readLine()) != null){
if(index == 0) {
index++;
continue; //skip first line
}
lines.add(line.split(","));
}
if(lines != null && !lines.isEmpty()) {
Collections.reverse(lines);
}
} catch(IOException ioe){
//IOException Handling
} catch(Exception e){
//Exception Handling
}
return lines;
}