I am out of ideas, I've been trying for the whole day to separate one file which has a format of :
AN Aixas
AN Aixirivall
AN Aixovall
AN Andorra la Vella
BR Salto do Mandira
BR Salto do Norte
BR Salto Dollman
BR Salto Grande
BR Salto Pilao
...
and so one, into different files by the name of the Country "AA.txt" and to include all the cities in these separate files. But my program only writes to a certain bunch of files and I cannot figure out why.
I've tried all the writing files classes - same result.
Here is the result, all worked but on a certain bunch of files only.
Here is the code :
package com.fileorganizer;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
public class File2 implements Cloneable {
static InputStream fis = null;
static BufferedReader br = null;
static String state = "";
static String tmp = "";
static File file = null;
static FileWriter fw = null;
static BufferedWriter bw = null;
public static void main(String[] args) {
int a = 0;
try {
fis = new FileInputStream(
new File(
"/Users/Mihail/Documents/WorkSpace/Parse-Starter-Project-1.8.2/ParseStarterProject/res/raw/cities.txt"));
br = new BufferedReader(new InputStreamReader(fis));
String line = null;
while ((line = br.readLine()) != null) {
state = line.substring(0, 2);
if (state.substring(0, 1).matches("^[A-Z]+$")
&& state.substring(1, 2).matches("^[A-Z]+$")
&& !tmp.equals(state)) {
file = new File(
"/Users/Mihail/Documents/WorkSpace/Parse-Starter-Project-1.8.2/ParseStarterProject/res/raw/countriesFolder/"
+ state + ".txt");
fw = new FileWriter(file.getAbsoluteFile());
bw = new BufferedWriter(fw);
tmp = state;
}
bw.write(line.substring(3) + "\n");
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (br != null)
br.close();
} catch (Exception ex) {
}
}
}
}
I am really sorry for such a dumb question. Please help
You don't close bw anywhere, so the contents in the BufferedWriter's buffer are lost.
Related
I'm trying to introduce a line break at every 100th character of the line from the existing file.But it doesn't write anything to it. below is the code written in java to read the existing file and write to it with a temporary file.
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
public class ReplaceFileContents {
public static void main(String[] args) {
new ReplaceFileContents().replace();
}
public void replace() {
String oldFileName = "Changed1.ldif";
String tmpFileName = "Changed2.ldif";
BufferedReader br = null;
BufferedWriter bw = null;
try {
br = new BufferedReader(new FileReader(oldFileName));
bw = new BufferedWriter(new FileWriter(tmpFileName));
String line;
while ((line = br.readLine()) != null) {
line.replaceAll("(.{100})", "$1\n");
}
} catch (Exception e) {
return;
} finally {
try {
if(br != null)
br.close();
} catch (IOException e) {
//
}
try {
if(bw != null)
bw.close();
} catch (IOException e) {
//
}
}
// Once everything is complete, delete old file..
File oldFile = new File(oldFileName);
oldFile.delete();
// And rename tmp file's name to old file name
File newFile = new File(tmpFileName);
newFile.renameTo(oldFile);
}
}
while ((line = br.readLine()) != null) {
line.replaceAll("(.{100})", "$1\n");
}
First off, line.replaceAll does not replace your line variable with the result. Because Strings are immutable, this method returns the new string, so your line should be line = line.replaceAll(....
Second, you're never writing the new String back into the file. Using replaceAll doesn't change the file itself in any way. Instead, try using your bw object to write the new String to the same line.
From what you've published here, you never try to write line back to bw. Try this:
package hello;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
public class Test {
public static void main(String[] args) {
new Test().replace();
}
public void replace() {
String oldFileName = "d:\\1.txt";
String tmpFileName = "d:\\2.txt";
BufferedReader br = null;
BufferedWriter bw = null;
try {
br = new BufferedReader(new FileReader(oldFileName));
bw = new BufferedWriter(new FileWriter(tmpFileName));
String line;
while ((line = br.readLine()) != null) {
line = line.replaceAll("(.{100})", "$1\n");
bw.write(line);
}
} catch (Exception e) {
return;
} finally {
try {
if(br != null)
br.close();
} catch (IOException e) {
//
}
try {
if(bw != null)
bw.close();
} catch (IOException e) {
//
}
}
// Once everything is complete, delete old file..
File oldFile = new File(oldFileName);
oldFile.delete();
// And rename tmp file's name to old file name
File newFile = new File(tmpFileName);
newFile.renameTo(oldFile);
}
}
You never try to write line back to bw;
String#replaceAll will return the copy of the source not the original String;
In my below code I wanted to replace the text "DEMO" with "Demographics" but instead of replacing the text it deletes the entire content of the text file.
Contents inside the file:
DEMO
data
morning
PS: I'm a beginner in java
package com.replace.main;
import java.io.*;
public class FileEdit {
public static void main(String[] args) {
BufferedReader br = null;
BufferedWriter bw = null;
String readLine, replacedData;
try {
bw = new BufferedWriter(
new FileWriter(
"Demg.ctl"));
br = new BufferedReader(
new FileReader(
"Demg.ctl"));
System.out.println(br.readLine()); //I Get Null Printed Here
while ((readLine = br.readLine())!= null) {
System.out.println("Inside While Loop");
System.out.println(readLine);
if (readLine.equals("DEMO")) {
System.out.println("Inside if loop");
replacedData = readLine.replaceAll("DEMO","Demographics");
}
}
System.out.println("After While");
br.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
You open a Writer to your file, but you don't write anything. This means that your file is replaced with an empty file.
Besides this you also need to close your writer, not just the reader.
And last but not least, your if condition is wrong.
if (readLine.equals("DEMO")) {
should read
if (readLine.contains("DEMO")) {
Otherwise it would only return true if your line contained "DEMO" but nothing else.
I'm updating the answer to my own question.
package com.replace.main;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
public class FileEdit
{
public static void main(String args[])
{
try
{
BufferedReader reader = new BufferedReader(new FileReader("Demg.ctl"));
String readLine = "";
String oldtext = "";
while((readLine = reader.readLine()) != null)
{
oldtext += readLine + "\r\n";
}
reader.close();
// To replace the text
String newtext = oldtext.replaceAll("DEMO", "Demographics");
FileWriter writer = new FileWriter("Demg.ctl");
writer.write(newtext);
writer.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
}
I asked a similar question before regarding I/O using Java.
I'm trying to copy a list of strings into another file.
package file;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
public class File {
public static void main(String[] args) {
FileWrite fW = new FileWrite();
try (BufferedReader br = new BufferedReader(new FileReader("B:\\inLarge.dat")))
{
String stCurrent;
while ((stCurrent = br.readLine()) != null) {
System.out.println(stCurrent);
fW.serializeAddress(stCurrent, stCurrent);
}
} catch (IOException e) {
e.printStackTrace();
}
//fW.serializeAddress("Boston", "Canada");
}
}
And
package file;
import java.io.BufferedWriter;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.ObjectOutputStream;
import java.io.PrintStream;
import java.io.Serializable;
import java.io.File;
import java.io.IOException;
public class FileWrite {
public void serializeAddress(String city, String country){
try
{
File file = new File("B:\\outLarge.txt");
if (!file.exists())
{
file.createNewFile();
}
FileWriter fw = new FileWriter(file.getAbsoluteFile());
BufferedWriter bw = new BufferedWriter(fw);
bw.write(city + " " + country);
bw.close();
System.out.println("Done");
}
catch(Exception ex)
{
ex.printStackTrace();
}
}
}
But the ending output file has only one result, how do I make it copy everything?
I am thinking buffered-writer somehow needs to be in the loop to write new ones on top of existing ones? But not sure how to implement that.
Thanks a lot.
You are overwriting the file contents every time you call your serialize method, because you didn't open the file in append mode. To prevent overwriting, open the file in append mode:
FileWriter fw = new FileWriter(file.getAbsoluteFile(), true);
However, this is one case where the solution is probably over-engineered. For efficiency you really should be opening your file just once. Here's an example:
public static void main(final String[] args) {
try {
final BufferedReader reader = new BufferedReader(new FileReader("infile.txt"));
final PrintWriter writer = new PrintWriter(new File("outfile.txt"));
String inputLine;
while((inputLine = reader.readLine()) != null) {
writer.println(inputLine);
}
reader.close();
writer.close();
} catch(final Exception e) {
e.printStackTrace();
}
}
You're overwriting the existing file every time you open it. Instead append to it.
Change
FileWriter fw = new FileWriter(file.getAbsoluteFile());
to
FileWriter fw = new FileWriter(file.getAbsoluteFile(), true);
When trying to create two methods for counting the no. of rows and reading the values of a file, only one of these methods got executed and another is not executed showing the following error :Exception in thread "main" java.lang.RuntimeException: java.io.IOException: Read error
Please look at the following code:
package com.ibm.csvreader;
import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;
import java.io.*;
public class CsvFileReader2 {
public static class opencsvfile {
HashMap <String , String> map= new HashMap <String, String> ();
//csv file containing data
// FileReader strFile = new FileReader("C:/Users/vmuser/Desktop/SampleUpload.csv");
//create BufferedReader to read csv file
// BufferedReader br = new BufferedReader((strFile));
String strLine = "";
int lineNumber ;
public void countrows(FileInputStream fstream) throws Exception{
DataInputStream strFile = new DataInputStream(fstream);
BufferedReader br = new BufferedReader( new InputStreamReader (strFile));
lineNumber =0;
while( (strLine = br.readLine()) != null) {
lineNumber++;
}
System.out.println("no.of rows are :" +lineNumber);
br.close();
}
public void readfile(FileInputStream fstream) throws Exception{
DataInputStream strFile = new DataInputStream(fstream);
BufferedReader br = new BufferedReader( new InputStreamReader (strFile));
lineNumber =0;
while( (strLine = br.readLine()) != null) {
lineNumber++;
String[] tokens = strLine.split(",");
String key = tokens[0].trim();
String nodes = tokens[1].trim();
map.put(key, nodes);
}
System.out.println("map is" + map );
br.close();
System.out.println("File is Closed");
}
}
public static void main(String[] args) throws IOException {
File fl = new File ("C:/Users/vmuser/Desktop/SampleUpload.csv");
FileInputStream fstream = new FileInputStream(fl);
opencsvfile f=new opencsvfile();
try {
f.countrows(fstream);
f.readfile(fstream);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
Just a small modification will do the work:
package com.ibm.csvreader;
import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;
import java.io.*;
public class CsvFileReader2 {
public static class opencsvfile {
HashMap <String , String> map= new HashMap <String, String> ();
//csv file containing data
// FileReader strFile = new FileReader("C:/Users/vmuser/Desktop/SampleUpload.csv");
//create BufferedReader to read csv file
// BufferedReader br = new BufferedReader((strFile));
String strLine = "";
int lineNumber ;
public void countrows(FileInputStream fstream) throws Exception{
DataInputStream strFile = new DataInputStream(fstream);
BufferedReader br = new BufferedReader( new InputStreamReader (strFile));
lineNumber =0;
while( (strLine = br.readLine()) != null) {
lineNumber++;
}
System.out.println("no.of rows are :" +lineNumber);
br.close();
}
public void readfile(FileInputStream fstream) throws Exception{
DataInputStream strFile = new DataInputStream(fstream);
BufferedReader br = new BufferedReader( new InputStreamReader (strFile));
lineNumber =0;
while( (strLine = br.readLine()) != null) {
lineNumber++;
String[] tokens = strLine.split(",");
String key = tokens[0].trim();
String nodes = tokens[1].trim();
map.put(key, nodes);
}
System.out.println("map is" + map );
br.close();
System.out.println("File is Closed");
}
}
public static void main(String[] args) throws IOException {
File fl = new File ("C:/Users/vmuser/Desktop/SampleUpload.csv");
FileInputStream fstream = new FileInputStream(fl);
opencsvfile f=new opencsvfile();
try {
f.countrows(fstream);
fstream = new FileInputStream(fl);//include this line
f.readfile(fstream);
} catch (Exception e) {
throw new RuntimeException(e);
}
finally{
if(fstream!=null)
fstream.close();//be sure to close all streams at last
}
}
}
Close all other streams as well. Above code will work for you.Cheers.
When you close your BufferedReader, it also closes the nested classes, including the FileInputStream.
Instead of closing it, you should try and reset() it to restart reading it from the start.
Or you must re-open the FileInputStream.
I am trying to read in a technical paper, separate all the sentences, use a filter to find key terms and phrases in the sentences, and then create my own abstract.
What I have so far is two BufferedReaders reading a text file with a paragraph in it, and my filter being read in. Each line is then being stored into an ArrayList and printed to the console to test if they are being read correctly.
I want to know if I am approaching this the correct way by using a BufferedReader instead of a Scanner. I just want to be able to print out all the sentences after a '.' (dot), a '!' (exclamation-point), or a '?' (question-mark) for right now, so I know that the file is being read correctly.
This is my code so far:
import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;
import java.io.*;
import java.util.Scanner;
public class Filtering {
public static void main(String[] args) throws IOException {
ArrayList<String> lines1 = new ArrayList<String>();
ArrayList<String> lines2 = new ArrayList<String>();
try {
FileInputStream fstream1 = new FileInputStream("paper.txt");
FileInputStream fstream2 = new FileInputStream("filter2.txt");
DataInputStream inStream1 = new DataInputStream (fstream1);
DataInputStream inStream2 = new DataInputStream (fstream2);
BufferedReader br1 = new BufferedReader(
new InputStreamReader(inStream1));
BufferedReader br2 = new BufferedReader(
new InputStreamReader(inStream2));
String strLine1;
String strLine2;
while ((strLine1 = br1.readLine()) != null) {
lines1.add(strLine1);
}
while ((strLine2 = br2.readLine()) != null) {
lines2.add(strLine2);
}
inStream1.close();
inStream2.close();
}
catch (Exception e) {
System.err.println("Error: " + e.getMessage());
}
System.out.println(lines1);
System.out.println(lines2);
}
}
It is a good practice to use a BufferedReader to read any File as it will buffer the File instead of accessing each bytes one by one
The DataInputStream is not needed
You should specify a character encoding in your InputStreamReader
You could accumulate all your string in a StringBuilder so that you have the whole text in a single reference
You may want to look into BreakIterator to split your text into sentences. Have a look at getSentenceInstance().
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.text.BreakIterator;
public class Filtering {
public static void main(String[] args) throws IOException {
File paperFile = new File("paper.txt");
File filterFile = new File("filter2.txt");
// If you want you could roughly initiate the stringbuilders to their
// approximate future size
StringBuilder paper = new StringBuilder();
StringBuilder filter2 = new StringBuilder();
FileInputStream fstream1 = null;
FileInputStream fstream2 = null;
try {
fstream1 = new FileInputStream(paperFile);
fstream2 = new FileInputStream(filterFile);
BufferedReader br1 = new BufferedReader(new InputStreamReader(fstream1, "UTF-8"));
BufferedReader br2 = new BufferedReader(new InputStreamReader(fstream2, "UTF-8"));
String strLine1;
String strLine2;
while ((strLine1 = br1.readLine()) != null) {
paper.append(strLine1).append('\n');
}
while ((strLine2 = br2.readLine()) != null) {
filter2.append(strLine2).append('\n');
}
}
catch (Exception e) {
System.err.println("Error: " + e.getMessage());
} finally {
if (fstream1 != null) {
fstream1.close();
}
if (fstream2 != null) {
fstream2.close();
}
}
String paperString = paper.toString();
String filterString = filter2.toString();
System.out.println(paperString);
System.out.println(filterString);
// To break it into sentences
BreakIterator boundary = BreakIterator.getSentenceInstance();
boundary.setText(paperString);
int start = boundary.first();
for (int end = boundary.next(); end != BreakIterator.DONE; start = end, end = boundary.next()) {
System.out.println(paper.substring(start, end));
}
}
}