I have a problem with C# read(){} function. When I open and read my document it does not read the first line:
private static void read(string file, Konteineris butas)
{
using (StreamReader reader = new StreamReader(#file))
{
string line;
line = reader.ReadLine();
while (null != (line = reader.ReadLine()))
{
string[] values = line.Split(';');
int nr = Convert.ToInt16(values[0]);
double plotas = Convert.ToDouble(values[1]);
int kambariusk = Convert.ToInt16(values[2]);
int kaina = Convert.ToInt32(values[3]);
string tnr = values[4];
Apartaments apart = new Butas(nr,plotas,kambariusk,kaina,tnr); // array of apartaments
apartaments.addapartament(apart);
}
}
}
the text file:
1;25,4;1;25000;867467212 // skips this line...
2;26,4;2;100000;867467212
3;75,4;3;2100;867467212
4;65,4;4;15000;867467212
Remove the first call to line = reader.ReadLine(); You are calling ReadLine() your loop, so you don't need it there.
Because you do a line = reader.ReadLine(); then follow it up with the same code in the while loop, by the time it hits it's first iteration of the loop, it's already done a .ReadLine() twice, thus is on the second line of the file.
Remove the line = reader.ReadLine(); from the code and retry.
private static void read(string file, Konteineris butas)
{
using (StreamReader reader = new StreamReader(#file))
{
string line;
line = reader.ReadLine();
while (null != (line = reader.ReadLine()))
{
string[] values = line.Split(';');
int nr = Convert.ToInt16(values[0]);
double plotas = Convert.ToDouble(values[1]);
int kambariusk = Convert.ToInt16(values[2]);
int kaina = Convert.ToInt32(values[3]);
string tnr = values[4];
Apartaments apart = new Apartaments(nr,plotas,kambariusk,kaina,tnr); // array of apartaments
apartaments.addapartament(apart);
}
}
}
remove this. since your while condition does this already and you will jump over the first line based on this call.
line = reader.ReadLine(); gives you a new line every time you call it.
So in your while condition you get your second line without using your first.
way1:
private static void read(string file, Konteineris butas)
{
using (StreamReader reader = new StreamReader(#file))
{
string line;
while (null != (line = reader.ReadLine()))
{
string[] values = line.Split(';');
int nr = Convert.ToInt16(values[0]);
double plotas = Convert.ToDouble(values[1]);
int kambariusk = Convert.ToInt16(values[2]);
int kaina = Convert.ToInt32(values[3]);
string tnr = values[4];
Apartaments apart = new Apartaments(nr,plotas,kambariusk,kaina,tnr); // array of apartaments
apartaments.addapartament(apart);
}
}
}
way2:
private static void read(string file, Konteineris butas)
{
using (StreamReader reader = new StreamReader(#file))
{
string line;
while (line!=null)
{
line = reader.ReadLine();
string[] values = line.Split(';');
int nr = Convert.ToInt16(values[0]);
double plotas = Convert.ToDouble(values[1]);
int kambariusk = Convert.ToInt16(values[2]);
int kaina = Convert.ToInt32(values[3]);
string tnr = values[4];
Apartaments apart = new Apartaments(nr,plotas,kambariusk,kaina,tnr); // array of apartaments
apartaments.addapartament(apart);
}
}
}
Related
Write a program that shall calculate the vocabulary richness of a text in a file and the frequency of the most common word. The vocabulary richness is the number of words in the text divided by the number of distinct words. The frequency of a word is the number of times the word is mentioned in the text divided by the total number of words in the text.
Define and implement class WordCounter with two private fields String word and int count, constructor WordCounter(String word), and public methods String getName(), int getCount(), and void addToCounter().
Define and implement class Corpus (as in text corpus) with one private field ArrayList<WordCounter> words, constructor Corpus(BufferedReader infile), and public methods double getVocabularyRichness() and String getMostFrequentWord().
Implement a test program (as the public static void main method in Corpus) that reads all files in a specific folder, creates a Corpus object from each (previously opened) file, and saves the requested statistics into another file stats.csv. You can either create a new Corpus object for each file or define an ArrayList<Corpus> of the corpora.
Each line of the CSV file must consist of three fields separated by commas (but no spaces!): the file name, the vocabulary richness, and the most frequently used word. Run your program on all Shakespeare's plays. Submit the CSV file together with the Java file.
I wrote what I think is the correct implementation of the HW problem because it works properly for some of the text files, however only the words.get(i).getName() (I tested with words.get(i).getCount()) method will print a blank space for some of the files. I have tried everything, and can't seem to figure it out. Can you please give me a hint or some guidance as to how to fix this issue?
public class Corpus {
private ArrayList<WordCounter> words = new ArrayList <WordCounter>() ;
Corpus(BufferedReader infile){
String ln;
try {
while((ln = infile.readLine()) != null) {
for (String word : ln.toLowerCase().split("([,.\\s]+)")) {
int reference = 0;
for(int i = 0; i < words.size(); i++) {
if (word.equals(words.get(i).getName())) {
reference++;
words.get(i).addToCounter();
} }
if (reference==0) { words.add(new WordCounter(word)); }
}
}
} catch (IOException e) {
e.printStackTrace();
}
}
public double getVocabularyRichness() {
int word_count=0;
for(int i = 0; i < words.size(); i++) {
word_count=word_count+words.get(i).getCount();
}
return (double)word_count/(double)words.size();
}
public String getMostFrequentWord() {
String winner = "*AN ERROR OCCURRED*";
int max_count = 0;
for(int i = 0; i < words.size(); i++) {
if(words.get(i).getCount() > max_count){
max_count = words.get(i).getCount();
}
}
for(int i = 0; i < words.size(); i++) {
if(words.get(i).getCount() == max_count){
winner = words.get(i).getName();
}
}
//winner="Test " + String.valueOf(words.get(i).getName());;
//return String.valueOf(max_count);
return winner;
}
public static void main(String [] args) throws Exception{
BufferedWriter writer = null;
File folder_location = new File("/Users/joaquindelaguardia/Desktop/Shakespeare");
File[] file_array = folder_location.listFiles();
for(File iteration_file: file_array) {
FileReader current_file = new FileReader(iteration_file);
BufferedReader infile = new BufferedReader(current_file);
Corpus obj1 = new Corpus(infile);
String file_name = iteration_file.getName();
String frequent_word = obj1.getMostFrequentWord();
String vocabulary_richness = String.valueOf(obj1.getVocabularyRichness());
System.out.println(file_name);
System.out.println(frequent_word);
System.out.println(vocabulary_richness);
System.out.println("-----------------------------");
//FileWriter file_writer = new FileWriter("/Users/joaquindelaguardia/Desktop/stats.csv");
//writer = new BufferedWriter(file_writer);
//String output = file_name+", "+frequent_word+", "+vocabulary_richness + "\n";
//writer.append(output);
}
//writer.close();
}
}
public class WordCounter {
private String word;
private int count=1;
WordCounter(String word){
this.word=word;
}
public String getName() {
return word;
}
public int getCount() {
return count;
}
public void addToCounter() {
count++;
}
}
Im testing the information by printing before appending to file, and as you can see with the small fragment of the output included below, for some cases it prints the most common word (and) while in the second case it doesn't print anything.
shakespeare-lovers-62.txt
and
2.2409948542024014
shakespeare-julius-26.txt
6.413205537806177
so that later i can parse the array and if the line contains 3 doubles store it into an array of object type? ill later have to store the lines with 3 doubles into another array.
here's an example of my code so far
public static void readFile(){
Scanner scnr = null;
File info = new File("info.txt");
try {
scnr = new Scanner(info);
} catch (FileNotFoundException e) {
System.out.println("file not found");
e.printStackTrace();
}
int counterLines = 0;
String nextLine = "";
while(scnr.hasNextLine()){
nextLine = scnr.nextLine();
counterLines ++;
}
System.out.println(counterLines);
String[] infoArray = new String[counterLines];
for(int i = 0; i < counterLines; i++){
infoArray[i] = scnr.nextLine();
System.out.println(infoArray[i]);
You can probably spilt the text of the file into individual words using String.split() which gives you a String array.
I am parsing big text files and it's working fine for some time but after few minutes it give me exception (An unhandled exception of type 'System.UnauthorizedAccessException' occurred in System.Core.dll
Additional information: Access to the path is denied.)
I get exception on below mention line.
accessor = MemoryMapped.CreateViewAccessor(offset, length, MemoryMappedFileAccess.Read);
Below is my function
public static void CityStateZipAndZip4(string FilePath,long offset,long length,string spName)
{
try
{
long indexBreak = offset;
string fileName = Path.GetFileName(FilePath);
if (fileName.Contains(".txt"))
fileName = fileName.Replace(".txt", "");
System.IO.FileStream file = new System.IO.FileStream(#FilePath, FileMode.Open,FileAccess.Read, FileShare.Read );
Int64 b = file.Length;
MemoryMappedFile MemoryMapped = MemoryMappedFile.CreateFromFile(file, fileName, b, MemoryMappedFileAccess.Read, null, HandleInheritability.Inheritable, false);
using (MemoryMapped)
{
//long offset = 182; // 256 megabytes
//long length = 364; // 512 megabytes
MemoryMappedViewAccessor accessor = MemoryMapped.CreateViewAccessor(offset, length, MemoryMappedFileAccess.Read);
byte byteValue;
int index = 0;
int count = 0;
StringBuilder message = new StringBuilder();
do
{
if (indexBreak == index)
{
count = count + 1;
accessor.Dispose();
string NewRecord = message.ToString();
offset = offset + indexBreak;
length = length + indexBreak;
if (NewRecord.IndexOf("'") != -1)
{ NewRecord = NewRecord.Replace("'", "''"); }
// string Sql = "insert into " + DBTableName + " (ID, DataString) values( " + count + ",'" + NewRecord + "')";
string Code = "";
if (spName == AppConfig.sp_CityStateZip)
{
Code = NewRecord.Trim().Substring(0, 1);
}
InsertUpdateAndDeleteDB(spName, NewRecord.Trim (), Code);
accessor = MemoryMapped.CreateViewAccessor(offset, length, MemoryMappedFileAccess.Read);
message = new StringBuilder();
index = 0;
//break;
}
byteValue = accessor.ReadByte(index);
if (byteValue != 0)
{
char asciiChar = (char)byteValue;
message.Append(asciiChar);
}
index++;
} while (byteValue != 0);
}
MemoryMapped.Dispose();
}
catch (FileNotFoundException)
{
Console.WriteLine("Memory-mapped file does not exist. Run Process A first.");
}
}
Somewhere deep in resource processing code we have something like this:
try {
// Try loading some strings here.
} catch {
// Oops, could not load strings, try another way.
}
Exception is thrown and handled already, it would never show up in your application. The only way to see it is to attach debugger and observe this message.
As you could see from the code, it has nothing to do with your problem. The real problem here is what debugger shows you something you should not see.
Run the solution without debugging mode and it works fine.
This exception means that your program does not get Read access to the file from Windows.
Have you made sure that this file is not locked when your program tries to read it ?
For example, it could be a file that your own program is currently using.
If not, try to run your program as an Administrator and see if it makes a difference.
If I use the File.getText() method in groovy
newFile().text or newFile().getText()
do I have to execute some closure statements to close the used file reader or will the method do it by itself?
It will do it by itself.
Calling new File( 'a.txt' ).text will call ResourceGroovyMethods.getText( File )
public static String getText(File file, String charset) throws IOException {
return IOGroovyMethods.getText(newReader(file, charset));
}
Which as you can see calls IOGroovyMethods.getText( BufferedReader ):
public static String getText(BufferedReader reader) throws IOException {
StringBuilder answer = new StringBuilder();
// reading the content of the file within a char buffer
// allow to keep the correct line endings
char[] charBuffer = new char[8192];
int nbCharRead /* = 0*/;
try {
while ((nbCharRead = reader.read(charBuffer)) != -1) {
// appends buffer
answer.append(charBuffer, 0, nbCharRead);
}
Reader temp = reader;
reader = null;
temp.close();
} finally {
closeWithWarning(reader);
}
return answer.toString();
}
Which as you can see, closes the Reader when done
Basically I'm creating an indoor navigation system in J2ME. I've put the location details in a .txt file i.e.
Locations names and their coordinates.
Edges with respective start node and end node as well as the weight (length of the node).
I put both details in the same file so users dont have to download multiple files to get their map working (it could become time consuming and seem complex).
So what i did is to seperate the deferent details by typing out location Names and coordinates first, After that I seperated that section from the next section which is the edges by drawing a line with multiple underscores.
Now the problem I'm having is parsing the different details into seperate arrays by setting up a command (while manually tokenizing the input stream) to check wether the the next token is an underscore.
If it is, (in pseudocode terms), move to the next line in the stream, create a new array and fill it up with the next set of details.
I found a some explanation/code HERE that does something similar but still parses into one array, although it manually tokenizes the input. Any ideas on what to do? Thanks
Text File Explanation
The text has the following format...
<--1stSection-->
/**
* Section one has the following format
* xCoordinate;yCoordinate;LocationName
*/
12;13;New York City
40;12;Washington D.C.
...e.t.c
_________________________ <--(underscore divider)
<--2ndSection-->
/**
* Its actually an adjacency list but indirectly provides "edge" details.
* Its in this form
* StartNode/MainReferencePoint;Endnode1;distance2endNode1;Endnode2;distance2endNode2;...e.t.c
*/
philadelphia;Washington D.C.;7;New York City;2
New York City;Florida;24;Illinois;71
...e.t.c
package filereader;
import java.io.IOException;
import java.io.InputStream;
import java.util.Hashtable;
import java.util.Vector;
public class FileReader {
String locationSection;
String edgeSection;
Vector locations;
Vector edges;
public FileReader(String fileName) {
// read the contents into the string
InputStream is = getClass().getResourceAsStream(fileName);
StringBuffer sb = new StringBuffer();
int ch;
try {
while ((ch = is.read()) != -1) {
sb.append((char) ch);
}
} catch (IOException e2) {
e2.printStackTrace();
}
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
String text = sb.toString();
// separate locations and edges
String separator = "_________________________";
// read location section, without last end-of-line char
int endLocationSection = text.indexOf(separator) - 1;
locationSection = text.substring(0, endLocationSection);
// read edges section, without end-of-line char after separator
int startEdgeSection = endLocationSection + separator.length() + 3;
edgeSection = text.substring(startEdgeSection, text.length());
// parse locations and edges
locations = getLocationsVector(locationSection);
edges = getEdgesVector(edgeSection);
}
// parse locations section
public Vector getLocationsVector(String section) {
Vector result = new Vector();
int startLine = 0;
int endLine = section.indexOf('\n');
while (endLine != -1) {
String line = section.substring(startLine, endLine);
result.addElement(parseLocationsLine(line, ';'));
startLine = endLine + 1;
if (endLine == section.length() - 1)
break;
endLine = section.indexOf('\n', startLine);
// if no new line found, read to the end of string
endLine = (-1 == endLine) ? section.length() - 1 : endLine;
}
return result;
}
// parse edges section
public Vector getEdgesVector(String section) {
Vector result = new Vector();
int startLine = 0;
int endLine = section.indexOf('\n');
while (endLine != -1) {
String line = section.substring(startLine, endLine - 1);
result.addElement(parseEdgesLine(line, ';'));
startLine = endLine + 1;
if (endLine == section.length() + 1)
break;
endLine = section.indexOf('\n', startLine);
// if no new line found, read to the end of string
endLine = (-1 == endLine) ? section.length() + 1 : endLine;
}
return result;
}
// parse locations line
public Hashtable parseLocationsLine(String value, char splitBy) {
Hashtable result = new Hashtable();
int xCEnd = value.indexOf(splitBy);
int yCEnd = value.indexOf(splitBy, xCEnd + 1);
result.put("x", value.substring(0, xCEnd));
result.put("y", value.substring(xCEnd + 1, yCEnd));
result.put("location", value.substring(yCEnd + 1,
value.length() - 1));
return result;
}
// parse edges line
public Hashtable parseEdgesLine(String value, char splitBy) {
Hashtable result = new Hashtable();
int snEnd = value.indexOf(splitBy);
result.put("startnode", value.substring(0, snEnd));
int n = 1;
int start = snEnd + 1;
int enEnd = value.indexOf(splitBy, snEnd + 1);
int dstEnd = value.indexOf(splitBy, enEnd + 1);
while (enEnd != -1 && dstEnd != -1) {
result.put("endnode" + String.valueOf(n),
value.substring(start, enEnd));
result.put("distance" + String.valueOf(n), value.substring(
enEnd + 1, dstEnd));
start = dstEnd + 1;
enEnd = value.indexOf(splitBy, start);
if (dstEnd == value.length())
break;
dstEnd = value.indexOf(splitBy, enEnd + 1);
// if last endnode-distance pair, read to the end of line
dstEnd = (-1 == dstEnd) ? value.length() : dstEnd;
n++;
}
return result;
}
// getters for locations and edges
public Vector getLocations() {
return locations;
}
public Vector getEdges() {
return edges;
}
}
and somewhere in application screen:
fr = new FileReader("/map.txt");
Vector vct1 = fr.getLocations();
for (int i = 0; i < vct1.size(); i++) {
Hashtable location = (Hashtable) vct1.elementAt(i);
Enumeration en = location.keys();
String fv = "";
while (en.hasMoreElements()) {
String key = (String) en.nextElement();
String value = (String)location.get(key);
fv = fv + value + "-";
}
this.add(new LabelField(fv));
}
Vector vct2 = fr.getEdges();
for (int i = 0; i < vct2.size(); i++) {
Hashtable location = (Hashtable) vct2.elementAt(i);
Enumeration en = location.keys();
String fv = "";
while (en.hasMoreElements()) {
String key = (String) en.nextElement();
String value = (String)location.get(key);
fv = fv + value + "-";
}
this.add(new LabelField(fv));
}
it will be easy to get values from hashtable by keys:
(String)location.get("x")
(String)location.get("y")
(String)location.get("location")
(String)edge.get("startnode")
(String)edge.get("endnode1")
(String)edge.get("distance1")
(String)edge.get("endnode2")
(String)edge.get("distance2")
...