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combine two methods in Java together in this Java code

I want combine the two methods Just some error in my document parser, frequencyCounter and parseFiles thsi code.
I want all of frequencyCounter should be a function that should be executed from within parseFiles, and relevant information don't worry about the file's content should be passed to doSomething so that it knows what to print.
Right now I'm just keep messing up on how to put these two methods together, please give some advices
this is my main class:
public class Yolo {
public static void frodo() throws Exception {
int n; // number of keywords
Scanner sc = new Scanner(System.in);
System.out.println("number of keywords : ");
n = sc.nextInt();
for (int j = 0; j <= n; j++) {
Scanner scan = new Scanner(System.in);
System.out.println("give the testword : ");
String testWord = scan.next();
System.out.println(testWord);
File document = new File("path//to//doc1.txt");
boolean check = true;
try {
FileInputStream fstream = new FileInputStream(document);
BufferedReader br = new BufferedReader(new InputStreamReader(fstream));
String strLine;
strLine = br.readLine();
// Read File Line By Line
int count = 0;
while ((strLine = br.readLine()) != null) {
// check to see whether testWord occurs at least once in the
// line of text
check = strLine.toLowerCase().contains(testWord.toLowerCase());
if (check) {
// get the line
String[] lineWords = strLine.split("\\s+");
// System.out.println(strLine);
count++;
}
}
System.out.println(testWord + "frequency: " + count);
br.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}

The code below gives you this output:
Professor frequency: 54
engineering frequency: 188
data frequency: 2
mining frequency: 2
research frequency: 9
Though this is only for doc1, you've to add a loop to iterate on all the 5 documents.
public class yolo {
public static void frodo() throws Exception {
String[] keywords = { "Professor" , "engineering" , "data" , "mining" , "research"};
for(int i=0; i< keywords.length; i++){
String testWord = keywords[i];
File document = new File("path//to//doc1.txt");
boolean check = true;
try {
FileInputStream fstream = new FileInputStream(document);
BufferedReader br = new BufferedReader(new InputStreamReader(fstream));
String strLine;
strLine = br.readLine();
// Read File Line By Line
int count = 0;
while ((strLine = br.readLine()) != null) {
// check to see whether testWord occurs at least once in the
// line of text
check = strLine.toLowerCase().contains(testWord.toLowerCase());
if (check) {
// get the line
String[] lineWords = strLine.split("\\s+");
count++;
}
}
System.out.println(testWord + "frequency: " + count);
br.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
hope this helps!

java read only integers from file

If I have a file that contains for example:
results1: 2, 4, 5, 6, 7, 8, 9
results2: 5, 3, 7, 2, 8, 5, 2
I want to add the integers from each line to a array. One array
for each line. How can I do this with code that does only read the integers?
Here's what I got this far
String data = null;
try {
Scanner in = new Scanner(new File(myFile));
while (in.hasNextLine()) {
data = in.nextLine();
numbers.add(data);
}
in.close();
} catch (Exception e) {
}

Easy.
One line per array, not two as you have it. New line after each one.
Read each line as a String, discard the leading "resultsX:", and split what remains at a delimiter of your choosing (e.g. comma). Parse each into an integer and add it to a List.
I don't think that leading "results1: " is adding any value. Why do you have that?

public static void main(String[] args) throws IOException {
BufferedReader reader=null;
try {
reader = new BufferedReader(new FileReader(new File("PATH TO FILE")));
// Only works if File allways contains at least two lines ... all lines after the second
// will be ignored
System.out.println(String.format("Array 1 : %s", Arrays.toString(stringArray2IntArray(readNextLine(reader)))));
System.out.println(String.format("Array 2 : %s", Arrays.toString(stringArray2IntArray(readNextLine(reader)))));
} finally {
if (reader!=null) {
reader.close();
}
}
}
private static Integer[] stringArray2IntArray(String[] numStrings) {
List<Integer> result = new ArrayList<Integer>();
for (int i = 0; i < numStrings.length; i++) {
result.add(Integer.parseInt(numStrings[i].trim()));
}
return result.toArray(new Integer[numStrings.length]);
}
private static String[] readNextLine(BufferedReader reader) throws IOException {
return reader.readLine().split(":")[1].split(",");
}

Assuming you have an input file, like this:
2,4,5,6,7,8,9
5,3,7,2,8,5,2
here is a code snippet to load it:
String firstLine = "";
String secondLine = "";
File file = new File("path/to/file");
try {
BufferedReader br = new BufferedReader(new FileReader(file));
firstLine = br.readLine();
secondLine = br.readLine();
} catch(Exception e){
e.printStackTrace();
}
String[] firstResult = firstLine.split(",");
String[] secondResult = secondLine.split(",");
int[] firstIntegers = new int[firstResult.length];
for(int i = 0; i <= firstResult.length ; i++){
firstIntegers[i] = Integer.parseInt(firstResult[i]);
}
int[] secondIntegers = new int[secondResult.length];
for(int i = 0; i <= secondResult.length ; i++){
firstIntegers[i] = Integer.parseInt(secondResult[i]);
}

Open the file with a BufferedReader br and then read it line by line.
Store each line in an int array and add all those int arrays to a list. At the end, this list will contain all the int arrays that we wanted, so iterate this list to do whatever you want to do next.
String filePath = "/path/to/file";
BufferedReader br = null;
List<Integer[]> arrays = new ArrayList<>(); //this contains all the arrays that you want
try {
br = new BufferedReader(new FileReader(filePath));
String line = null;
while ((line = br.readLine()) != null) {
line = line.substring(line.indexOf(":")+2); //this starts the line from the first number
String[] stringArray = line.split(", ");
Integer[] array = new Integer[stringArray.length];
for (int i = 0; i < stringArray.length; ++i) {
array[i] = Integer.parseInt(stringArray[i]);
}
arrays.add(array);
}
} catch (FileNotFoundException ex) {
System.err.println(ex);
} catch (IOException ex) {
System.err.println(ex);
} finally {
try {
br.close();
} catch (Exception ex) {
System.err.println(ex);
}
}
Since ArrayLists keep insertion order, then, e.g., arrays.get(3) will give you the array of the fourth line (if there is such a line) and arrays.size() will give you the number of lines (i.e., int arrays) that are stored.

java bufferedReader. how to read parts of a line

Ok now, here's my question. I wrote an algorithm to do specific things. Currently I create my processes myself in the class constructor and store them in a priority queue. However I want to be able to write a .txt file with multiple lines. Each line will represent a process with its different attributes separated by space. Here's what my .txt will look like:
P1 0 8
P2 1 4
P3 2 9
P4 3 3
END 4 9999
p1, p2... etc are the names of each process. Then the second column is the first attribute and the third column is the second attribute.
I need to be able to read each column at a time and store the value in my processes. How can I read those values and distinguish between them? (treat them as separate things)

So you want to read the file line-by-line and separate each line?
BufferReader in=new BufferedReader...
String line;
while ((line=in.readLine())!=null) {
String[] data=line.split(" ");
//now, data will be a array which contains the data
//data[0] = the first item in the line
//data[1] = the first number
//data[2] = the second number
}

Have a look at the java.util.Scanner class, it can help to read separate tokens from a Reader.
It has methods to read the next token as an integer, as a string or many other types. There are also some examples in the class Javadoc...

You got both whitespace (seperating the attributes) and new line (seperates the whole process information) as seperators.
Using a BufferedReader, you could either read a whole line (reader.readLine()) to parse one whole process information and use String.split() to seperate the attributes (edit: see answer from dyslabs).
An obviously more performant (but less intuitive) approach is to read single characters (reader.read()) and check if you either read a whitespace- or a new-line-character:
// caution: code is not tested but shows the general approach
List<ProcessInformation> processInfo = new ArrayList<>();
String pInfoStr = new String[3];
int processInfoIndex = 0;
String[] processInfoHolder = new String[3];
String processInfo = "";
int c;
while( (c = reader.read()) != -1 ) {
if (Character.isWhitespace(c)) {
processInfoHolder[processInfoIndex++] = processInfo;
processInfoStr = "";
}
else if (c == 10) { // not sure if correct codepoint for whitespace
processInfo.add(new ProcessInfo(processInfoHolder));
processInfoIndex = 0;
}
else {
processInfoStr += c;
}
}
You could even more optimize this method by using StringBuilder.

In order to be able to read a file line by line I use readLine() != null while in order to retrieve the values separated by whitespace, use the split method and store each value of a single line in an array,
here's how I implemented your example:
public static void main(String[] args) {
// TODO Auto-generated method stub
BufferedReader buffer;
FileReader fileReader;
String p1[] = new String[4];
String p2[] = new String[4];
String p3[] = new String[4];
String p4[] = new String[4];
String end[] = new String[4];
try {
fileReader = new FileReader(new File("file.txt"));
buffer = new BufferedReader(fileReader);
String line;
line = buffer.readLine();
// ============= Read the fist line =============
p1 = line.split("\\s+");
while((line = buffer.readLine()) != null) {
// ============= Read the second line =============
p2 = line.split("\\s+");
// ============= Read the third line =============
if((line = buffer.readLine()) != null) {
p3 = line.split("\\s+");
}
// ============= Read the forth line =============
if((line = buffer.readLine()) != null) {
p4 = line.split("\\s+");
}
// ============= Read the last line =============
if((line = buffer.readLine()) != null) {
end = line.split("\\s+");
}
}
fileReader.close();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
int v1[] = new int[3];
int v2[] = new int[3];
int v3[] = new int[3];
int v4[] = new int[3];
int v_end[] = new int[3];
for (int i = 0 ; i < p1.length; i++)
System.out.print(p1[i]+ " ");
System.out.println();
for (int i = 0 ; i < p2.length; i++)
System.out.print(p2[i]+ " ");
System.out.println();
for (int i = 0 ; i < p3.length; i++)
System.out.print(p3[i]+ " ");
System.out.println();
for (int i = 0 ; i < p4.length; i++)
System.out.print(p4[i]+ " ");
System.out.println();
for (int i = 0 ; i < end.length; i++)
System.out.print(end[i]+ " ");
}

How to read N amount of lines from a file?

I am trying to practice reading text from a file in java. I am little stuck on how I can read N amount of lines, say the first 10 lines in a file and then add the lines in an ArrayList.
Say for example, the file contains 1-100 numbers, like so;
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- ....
I want to read the first 5 numbers, so 1,2,3,4,5 and add it to an array list. So far, this is what I have managed to do but I am stuck and have no clue what to do now.
ArrayList<Double> array = new ArrayList<Double>();
InputStream list = new BufferedInputStream(new FileInputStream("numbers.txt"));
for (double i = 0; i <= 5; ++i) {
// I know I need to add something here so the for loop read through
// the file but I have no idea how I can do this
array.add(i); // This is saying read 1 line and add it to arraylist,
// then read read second and so on
}

You could try using a Scanner and a counter:
ArrayList<Double> array = new ArrayList<Double>();
Scanner input = new Scanner(new File("numbers.txt"));
int counter = 0;
while(input.hasNextLine() && counter < 10)
{
array.add(Double.parseDouble(input.nextLine()));
counter++;
}
This should loop through 10 lines adding each to the arraylist as long as there is more inputs in the file.

See this How to read a large text file line by line using Java?
I think this will work:
BufferedReader br = new BufferedReader(new FileReader(file));
String line;
int i = 0;
while ((line = br.readLine()) != null)
{
if (i < 5)
{
// process the line.
i++;
}
}
br.close();

ArrayList<String> array = new ArrayList<String>();
//ArrayList of String (because you will read strings)
BufferedReader reader = null;
try {
reader = new BufferedReader(new FileReader("numbers.txt")); //to read the file
} catch (FileNotFoundException ex) { //file numbers.txt does not exists
System.err.println(ex.toString());
//here you should stop your program, or find another way to open some file
}
String line; //to store a read line
int N = 5; //max number of lines to read
int counter = 0; //current number of lines already read
try {
//read line by line with the readLine() method
while ((line = reader.readLine()) != null && counter < N) {
//check also the counter if it is smaller then desired amount of lines to read
array.add(line); //add the line to the ArrayList of strings
counter++; //update the counter of the read lines (increment by one)
}
//the while loop will exit if:
// there is no more line to read (i.e. line==null, i.e. N>#lines in the file)
// OR the desired amount of line was correctly read
reader.close(); //close the reader and related streams
} catch (IOException ex) { //if there is some input/output problem
System.err.println(ex.toString());
}

List<Integer> array = new ArrayList<>();
try (BufferedReader in = new BufferedReader(
new InputStreamReader(new FileInputStream("numbers.txt")))) {
for (int i = 0; i < 5; ++i) { // Loops 5 times
String line = in.readLine();
if (line == null) [ // End of file?
break;
}
// line does not contain line-ending.
int num = Integer.parseInt(line);
array.add(i);
}
} // Closes in.
System.out.println(array);

You can do this with:
try (BufferedReader reader = Files.newBufferedReader(Paths.get("numbers.txt"))) {
List<String> first10Numbers = reader.lines().limit(10).collect(Collectors.toList());
// do something with the list here
}
As complete example as JUnit test:
public class ReadFirstLinesOfFileTest {
#Test
public void shouldReadFirstTenNumbers() throws Exception {
Path p = Paths.get("numbers.txt");
Files.write(p, "0\n1\n2\n3\n4\n5\n6\n7\n8\n9\n10\n11\n12\n".getBytes());
try (BufferedReader reader = Files.newBufferedReader(Paths.get("numbers.txt"))) {
List<String> first10Numbers = reader.lines().limit(10).collect(Collectors.toList());
List<String> expected = Arrays.asList("0", "1", "2", "3", "4", "5", "6", "7", "8", "9");
Assert.assertArrayEquals(expected.toArray(), first10Numbers.toArray());
}
}
}

ArrayList<Double> myList = new ArrayList<Double>();
int numberOfLinesToRead = 5;
File f = new File("number.txt");
Scanner fileScanner = new Scanner(f);
for(int i=0; i<numberOfLinesToRead; i++){
myList.add(fileScanner.nextDouble());
}
Make sure you have "numberOfLinesToRead" lines in your file.

BufferedReader br = new BufferedReader(new FileReader(file));
List<String> nlines = IntStream.range(0, hlines)
.mapToObj(i -> readLine(br)).collect(Collectors.toList());
String readLine(BufferedReader reader) {
try {
return reader.readLine();
} catch (IOException e) {
throw new UncheckedIOException(e);
}
}

How to assign a text file's lines of integers into 2D tables in Java?

I have the sample.txt which contains 100 Integers (range 0-9) in every line formatted like this:
9 2 0 3 4 1 0 7 5 3 7 8 6 2 0 1 4 4 5 9 0 3 2 1 7 (etc... 100 numbers)
I want to scan the file and put every line into a 10x10 table. So:
public void loadTableFromFile(String filepath){
try (Scanner s = new Scanner(new BufferedReader(new FileReader(filepath)))) {
String line;
while (s.hasNextLine()) {
// WHAT HERE? THIS BLOCK DOES NOT WORK
/* if (s.hasNextInt()) {
//take int and put it in the table in the right position procedure
} else {
s.next();
} */
// END OF NOT WORKING BLOCK
}
} catch (FileNotFoundException e){
}
}

How about something like this?
public void loadTableFromFile(String filepath) {
Scanner s = null; // Our scanner.
try {
s = new Scanner(new BufferedReader(
new FileReader(filepath))); // get it from the file.
String line;
while (s.hasNextLine()) { // while we have lines.
line = s.nextLine(); // get a line.
StringTokenizer st = new StringTokenizer(line, " ");
int i = 0;
while (st.hasMoreTokens()) {
if (i != 0) {
System.out.print(' '); // add a space between elements.
}
System.out.print(st.nextToken().trim()); // print the next element.
i++;
if (i % 10 == 0) { // Add a new line every ten elements.
System.out.println();
}
}
System.out.println(); // between lines.
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} finally {
if (s != null)
s.close();
}
}

Here is a solution that reads the line of the file into an array of strings using the split by whitespace method, and then reads them in using a for loop. I threw any exceptions that might have occurred in the method declaration, alternatively, use the try catch loop as above (might be better design, not sure about that.)
public void loadTableFromFile(String filePath) throws IOException {
BufferedReader br = new BufferedReader(new FileReader(filePath));
String[] line = br.readLine().split(" ");
br.close(); // file only has 1 line with 100 integers
int[][] mydata = new int[10][10];
for(int i = 0; i < line.length; i++) {
mydata[i % 10][(int) (i / 10)] = Integer.parseInt(line[i]);
}
}
Now, if the file has more than one line, you could instead read the entire file line by line, and then use the above idea like this:
BufferedReader br = new BufferedReader(new FileReader(filePath));
String line1;
while((line1 = br.readLine()) != null) {
String[] line = line1.split(" ");
... // do above stuff of reading in 1 line here
}
br.close();

Try,
try (Scanner s = new Scanner(new BufferedReader(new FileReader(filepath)))) {
String line;
while (s.hasNextLine()) {
String[] strArr=line.split(" ");
for(int i=0;i<strArr.length;i++){
System.out.print(" "+strArr[i]);
if((i+1)%10==0){
System.out.println();
}
}
}
} catch (FileNotFoundException e){
}