We Keep Coding

How can I scope three different conditions using the same loop in Java?

I would like to count countX and countX using the same loop instead of creating three different loops. Is there any easy way approaching that?
public class Absence {
private static File file = new File("/Users/naplo.txt");
private static File file_out = new File("/Users/naplo_out.txt");
private static BufferedReader br = null;
private static BufferedWriter bw = null;
public static void main(String[] args) throws IOException {
int countSign = 0;
int countX = 0;
int countI = 0;
String sign = "#";
String absenceX = "X";
String absenceI = "I";
try {
br = new BufferedReader(new FileReader(file));
bw = new BufferedWriter(new FileWriter(file_out));
String st;
while ((st = br.readLine()) != null) {
for (String element : st.split(" ")) {
if (element.matches(sign)) {
countSign++;
continue;
}
if (element.matches(absenceX)) {
countX++;
continue;
}
if (element.matches(absenceI)) {
countI++;
}
}
}
System.out.println("2. exerc.: There are " + countSign + " rows int the file with that sign.");
System.out.println("3. exerc.: There are " + countX + " with sick note, and " + countI + " without sick note!");
} catch (FileNotFoundException ex) {
Logger.getLogger(Absence.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
text file example:
# 03 26
Jujuba Ibolya IXXXXXX
Maracuja Kolos XXXXXXX

I think you meant using less than 3 if statements. You can actually so it with no ifs.
In your for loop write this:
Countsign += (element.matches(sign)) ? 1 : 0;
CountX += (element.matches(absenceX)) ? 1 : 0;
CountI += (element.matches(absenceI)) ? 1 : 0;

Both answers check if the word (element) matches all regular expressions while this can (and should, if you ask me) be avoided since a word can match only one regex. I am referring to the continue part your original code has, which is good since you do not have to do any further checks.
So, I am leaving here one way to do it with Java 8 Streams in "one liner".
But let's assume the following regular expressions:
String absenceX = "X*";
String absenceI = "I.*";
and one more (for the sake of the example):
String onlyNumbers = "[0-9]*";
In order to have some matches on them.
The text is as you gave it.
public class Test {
public static void main(String[] args) throws IOException {
File desktop = new File(System.getProperty("user.home"), "Desktop");
File txtFile = new File(desktop, "test.txt");
String sign = "#";
String absenceX = "X*";
String absenceI = "I.*";
String onlyNumbers = "[0-9]*";
List<String> regexes = Arrays.asList(sign, absenceX, absenceI, onlyNumbers);
List<String> lines = Files.readAllLines(txtFile.toPath());
//#formatter:off
Map<String, Long> result = lines.stream()
.flatMap(line-> Stream.of(line.split(" "))) //map these lines to words
.map(word -> regexes.stream().filter(word::matches).findFirst()) //find the first regex this word matches
.filter(Optional::isPresent) //If it matches no regex, it will be ignored
.collect(Collectors.groupingBy(Optional::get, Collectors.counting())); //collect
System.out.println(result);
}
}
The result:
{X*=1, #=1, I.=2, [0-9]=2}
X*=1 came from word: XXXXXXX
#=1 came from word: #
I.*=2 came from words: IXXXXXX and Ibolya
[0-9]*=2 came from words: 03 and 06
Ignore the fact I load all lines in memory.

So I made it with the following lines to work. It escaped my attention that every character need to be separated from each other. Your ternary operation suggestion also nice so I will use it.
String myString;
while ((myString = br.readLine()) != null) {
String newString = myString.replaceAll("", " ").trim();
for (String element : newString.split(" ")) {
countSign += (element.matches(sign)) ? 1 : 0;
countX += (element.matches(absenceX)) ? 1 : 0;
countI += (element.matches(absenceI)) ? 1 : 0;

Reverse a string as per length of first word

I am new to Java Strings.
Actually I have the code to reverse words:
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class Test2 {
public static void main(String[] args) throws IOException
{
System.out.println("enter a sentence");
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String rev =br.readLine();
String [] bread = rev.split(" ");
for(int z =bread.length-1;z>=0;z--)
{
System.out.println(bread[z]);
}
}
}
For the above code I get:
Input :Bangalore is a city
Output: City is a Bangalore
But I want the output to be like below:
Input: Bangalore is a city
Output:cityaisba ng a lore
Another Example:
Input: Hello Iam New To Java.Java is object Oriented language.
Output: langu age Ori en tedo bjec ti sjava. javaToNe wIamolleH
Please help me out

Here is one way you could do it:
String rev = br.readLine();
String [] bread = rev.split(" ");
int revCounter = 0;
for(int z = bread.length - 1; z >= 0; z--)
{
String word = bread[z];
for(int i = 0; i < word.length(); i++)
{
// If char at current position in 'rev' was a space then
// just print space. Otherwise, print char from current word.
if(rev.charAt(revCounter) == ' ')
{
System.out.print(' ');
i--;
}
else
System.out.print(word.charAt(i));
revCounter++;
}
}

When I run your code I get following result:
city
a
is
Bangalore
So to have it in a single line, why don't you add a space and print a single line?
System.out.println("enter a sentence");
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String rev = br.readLine();
String[] bread = rev.split(" ");
for (int z = bread.length - 1; z >= 0; z--) {
System.out.print(bread[z] + " ");
}

I didn't check the validity of your code like GHajba did. But if you want spaces to remain on specific places it might be an option to remove all spaces and put them back according to their index in the original String.
Remove all
newBread = newBread.replace(" ", "");
Put them back
StringBuilder str = new StringBuilder(newBread);
for (int index = oldBread.indexOf(" ") ;
index >= 0 ;
index = oldBread.indexOf(" ", index + 1))
{
str.insert(index, ' ');
}
newBread = str.toString();
I came up with this quick and there might be better ways to do this, maybe without StringBuilder, but this might help you until you find a better way.

Try with this (i've used a string as input):
String original = "Bangalore is a city";
System.out.println("Original : "+original);
StringBuilder inverted = new StringBuilder();
StringBuilder output = new StringBuilder();
String temp = "";
String[] split = original.split("\\s+");
for (int i = split.length - 1; i >= 0; i--) {
inverted.append(split[i]);
}
temp = inverted.toString();
for (String string : split) {
int currLenght = string.length();
String substring = temp.substring(0,currLenght);
temp = temp.replaceAll(substring, "");
output.append(substring).append(" ");
}
System.out.println("Converted : "+output.toString());

Append the reversed words without the spaces into a StringBuffer.
StringBuffer b = new StringBuffer();
for (int i = bread.length-1; i >= 0 ; i--) {
b.append(bread[i]);
}
Then insert the spaces of the original String into the StringBuffer.
int spaceIndex, prevIndex = 0;
while ((spaceIndex = rev.indexOf(" ", prevIndex + 1)) != -1) {
b.insert(spaceIndex, ' ');
prevIndex = spaceIndex;
}

store 1d array from text file java

Am I reading the following input correctly?
Here is my code so far:
while ((line = br.readLine()) != null) {
line = line.substring(line.indexOf('[')+1, line.indexOf(']'));
String[] parts = line.split(",");
for (int i = 0; i< parts.length; i++) {
rangeNo[i]= Integer.parseInt(parts[i]);
System.out.println("{" + rangeNo[i] + "}");
}
}
and this is my input
[2,9], [3,11]
Also, when I try to print the value of rangeNo[3] it return 0 instead of 3
can someone help me out with this?

Do you expect [2,9], [3,11] to be in one line or two separate lines?
If its supposed to be one line then you might want to try something like this
Integer rangeNo[] = new Integer[10];
String line = "[2,9], [3,11]";
line = line.replace('[', ' ');
line = line.replace(']', ' ');
String[] parts = line.split(",");
for (int i = 0; i < parts.length; i++) {
rangeNo[i] = Integer.parseInt(parts[i].trim());
System.out.println("{" + rangeNo[i] + "}");
}

when you check here
line = line.substring(line.indexOf('[')+1, line.indexOf(']'));
it's matching first condition. i.e works fine for [2,9] not after that thus only 2 and 9 are getting stored here.
String[] parts = line.split(",");
so
parts[0]=2
parts[1]=9
parts[2]=0

Unable to find string in Java File

I have a Java program that works without issue for searching most strings but for some reason I am unable to have it find the below ina file which I know appears in the file. I am obviously trying to locate a certain element that has the value of 999 but i am unable to do so. Again this works for other strings just not the one below.
for(int i=0;i< inputFile.length;i++)
try {
br = new BufferedReader(new FileReader(inputFile[i]));
try {
while((line = br.readLine()) != null)
{
countLine++;
//System.out.println(line);
String[] words = line.split(" ");
for (String word : words) {
if (word.equals(inputSearch)) {
count++;
countBuffer++;
}
}
if(countBuffer > 0)
{
countBuffer = 0;
lineNumber += countLine + ",";
}
}
br.close();

If I understand your question, you could use a Pattern and Matcher and something like -
String toMatch = "<element>999</element>";
Pattern pattern = Pattern.compile(">\\s*999\\s*<");
Matcher match = pattern.matcher(toMatch);
int count = 0;
int start = 0;
while (start < toMatch.length() && match.find(start)) {
// Pattern found.
start = match.regionEnd() + 1;
count++;
}

How to read data from a specific column from csv file using jsp/java?

In my application I need to read a specific column of tab separated csv file using jsp. But I can read the data of full row not a specific column.
I need help this regard. Please help me
Thanks
mycode:
<%# page import="java.io.*"%>
<html>
<body>
<%
String fName = "c:\\csv\\myfile.csv";
String thisLine;
int count=0;
FileInputStream fis = new FileInputStream(fName);
DataInputStream myInput = new DataInputStream(fis);
int i=0;
%>
<table>
<%
while ((thisLine = myInput.readLine()) != null)
{
String strar[] = thisLine.split(",");
for(int j=0;j<strar.length;j++)
{
if(i!=0)
{
out.print(" " +strar[j]+ " ");
}
else
{
out.print(" <b>" +strar[j]+ "</b> ");
}
}
out.println("<br>");
i++;
}
%>
</table>
</body>
</html>

I don't think you can read specific column.Better to read entire row using CSVParser or you can read CSV line by line and split it and get String array then you can get specific column but yes you need to read whole row gain.
Try it.
String fName = "C:\\Amit\\abc.csv";
String thisLine;
int count = 0;
FileInputStream fis = new FileInputStream(fName);
DataInputStream myInput = new DataInputStream(fis);
int i = 0;
while ((thisLine = myInput.readLine()) != null) {
String strar[] = thisLine.split(",");
System.out.println(strar[3]);
// Here column 2
}
}
By this way you can read specific column.

I had a similar problem in Objective C the other day, but this is how I solved it.
This method assumes you know the column number of the data you want. (I.E. if you want column 1 of 6)
Read all the rows into strings and append them into one.
Data sample: (columns 1 to 6)
1,2,3,4,5,6
13,45,63,29,10,8
11,62,5,20,13,2
String 1 = 1,2,3,4,5,6
String 2 = 13,45,63,29,10,8
String 3 = 11,62,5,20,13,2
Then you should get this:
String combined = 1,2,3,4,5,6,13,45,63,29,10,8,11,62,5,20,13,2 //add in the missing "," when you concatenate strings
Next you need to split the string into an array of all values.
Use code somewhat like this: (written off the top of my head so may be off.)
String[] values = combined.split(",");
Now you should have something like this:
Values = `"1", "2", "3", ... etc`
The last step is to loop through the entire array and modulo for whatever column you need:
//Remember that java numbers arrays starting with 0.
//The key here is that all remainder 0 items fall into the first column. All remainder 1 items fall into the second column. And so on.
for(int i = 0; i < values.length(); i++)
{
//Column1 - Column6 -> array lists of size values.length/number of columns
//In this case they need to be size values.length/6
if(i % 6 == 0)
column1.add(values[i]);
else if(i % 6 == 1)
column2.add(values[i]);
else if(i % 6 == 2)
column3.add(values[i]);
else if(i % 6 == 3)
column4.add(values[i]);
else if(i % 6 == 4)
column5.add(values[i]);
else if(i % 6 == 5)
column6.add(values[i]);
}
~~~~~~~~~~~~~~~~
Edit:
You added code to your question. Above I was saving them into memory. You just loop through and print them out. In your while loop, split each line separately into an array and then either hardcode the column number or modulo the length of the array as the index.

public class ParseCSVs {
public static void main(String[] args) {
try {
// csv file containing data
String strFile = "./input//SIMNumbers.csv";
String line = "";
System.out.println("Enter line number to configure");
Scanner sc = new Scanner(System.in);
int lineNumber = sc.nextInt();
BufferedReader br = new BufferedReader(new FileReader(strFile));
if ((line = br.readLine()) != null) {
String cvsSplitBy = ",";
String blankCell = null;
// use comma as separator
String[] cols = line.split(cvsSplitBy);
for (int i = 0; i < cols.length; i++)
System.out.println("Coulmns = " + cols[i]);
// System.exit(0);
} else
System.out.println("No data found in csv");
} catch (IOException e) {
e.printStackTrace();
}
}