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Why it is advisable to wrap a BufferedWriter around any Writer whose write() operations may be costly, such as FileWriters and OutputStreamWriters?

java,file,filewriter,bufferedwriter
My question is, whether it is direct use, as shown below; class Test{ public static void main(String args[]){ try{ FileWriter fo =new FileWriter("somex.txt"); int arr[] = {9}; for(int i =0; i <arr.length; i++){ fo .write(arr[i]); // this is very costly. } fo.write(b); fo.close(); System.out.println("...."); }catch(Exception e){system.out.println(e);} } } OR coding...

Using FileWriter Within a Function; File Should Already Exist

java,filewriter
Okay, so within the distributionA function, I want to open and write to the same file that I successfully have written to already in main, but it won't recognize writer as a variable. I tried using append, but it would sometimes write over the text that I wanted to keep....

Write JSON in a file in subpackage using Java in WIN7

java,json,filewriter
I have a Java class in a package called for example com.project.test and I want to write some JSON in a file called Output.json which is located in a subpackage called com.project.test.sources. This is the code I have tried : String gsonGraphe = gson.toJson(graphe); /* This is the JSON code...

Writing to file in java using BufferedWriter

java,filewriter,random-sample,bufferedwriter,file-writing
I'm trying to take some random samples from a file and do some operations and then write them to another file. But I'm having trouble writing to a file in the grepLine method which can be found below. Inside the while loop of the grepLine function, I get a blank...

Java FileWriter lost special characters [duplicate]

java,special-characters,filewriter
This question already has an answer here: Java BufferedWriter object with utf-8 3 answers I've this code //write a file in a specific directory public static void writeFile(String comment, String outputFileName) { FileWriter fWriter = null; BufferedWriter writer = null; try { fWriter = new FileWriter(outputFileName,true); writer = new...

How to overwrite a file in Chrome App?

javascript,google-chrome,filesystems,google-chrome-app,filewriter
I followed this example: chrome.fileSystem.chooseEntry({type:'openDirectory'}, function(entry) { chrome.fileSystem.getWritableEntry(entry, function(entry) { entry.getFile('file1.txt', {create:true}, function(entry) { entry.createWriter(function(writer) { writer.write(new Blob(['Lorem'], {type: 'text/plain'})); }); }); entry.getFile('file2.txt', {create:true}, function(entry) { entry.createWriter(function(writer) { writer.write(new Blob(['Ipsum'], {type: 'text/plain'})); }); }); }); }); to overwrite some existing file file1.txt and...

Java - Writing and Reading ArrayList to and from .txt file - BufferedWriter

java,bufferedreader,filereader,filewriter,bufferedwriter
Some Background: I'm making an RPG text based game for class, and I'm using an ArrayList for the inventory, since of course, it will constantly be changing whenever another item is added. I want to be able to save this ArrayList into a txt file and I want to be...

Buffered Writer unable to process from array [closed]

java,arrays,ascii,filewriter,bufferedwriter
I am using a bufferedwriter to write to a file from an array: int[] scores = new int[5]; for (int i = 0; i < 5; i++) { scores[i] = 2; //Array of twos } try { BufferedWriter output = new BufferedWriter(new FileWriter(new File("Scores.txt"))); output.flush(); for (int i = 0;...

FileWriter out of memory [duplicate]

java,out-of-memory,filewriter
This question already has an answer here: Java difference between FileWriter and BufferedWriter 5 answers I want to format and write the contents of a large Map (1.785.530 entries) to a text file. After about 85% of the entries are processed, it gets very slow and then I get...

Java: BufferedReader Keeps Writing Values 128-159 as 63 When Converting to Char

java,bufferedreader,filereader,filewriter,bufferedwriter
I am trying to write a hex editor. I'm trying to store values by writing a char to a text file. For some reason every decimal number 128-159 is being written or read (not sure which) as 63. I took measures to isolate the problem. Here's an example of it...

How to copy content of a file to another file but at the top of the file in Java [duplicate]

java,file,filereader,fileinputstream,filewriter
This question already has an answer here: Java. How to append text to top of file.txt [duplicate] 3 answers I would liked to copy the content of file "Convert.sql" to file "Entity.sql" without overriding the "Entity.sql" file. This part i've been able to do it but in addition to...

Size of file goes into GB's on writing some text in it

java,filewriter
For learning File read and write i have written a method in which i am writing some result into a file. On running the program the file size goes into GB's and i have to stop the program in between, which i was not expecting. I am not sure what...

Does Java's FileWriter object attempt to create a file if file does not exist?

java,io,filewriter,java-api
I am seeking to clarify what the Java API documentation states about the FileWriter class. The documentation states the following: constructor: Constructs a FileWriter object given a file name. public FileWriter(String fileName) throws IOException fileName - String The system-dependent filename. IOException - if the named file exists but is a...

How to append text to file in Java 8 using specified Charset

java,file,logging,java-8,filewriter
I'm looking for an easy and save solution to append text to a existing file in Java 8 using a specified Charset cs. The solution which I found here deals with the standard Charset which is a no-go in my situation.

Half file transferring in c# via socket?

sockets,c#-4.0,file-transfer,filewriter
I am developing the file transfer application via middle level greedy routing in which file sends to greedy and greedy sends file again to router but he problem is some time client receives complete file and some time it receive some part of file Here my code goes Server Side...

Reading a string below a string from a file

java,string,filewriter,printwriter
For example, I were to save contact details on a .txt file and after that is saved, I would want to view the contact details of the person only by entering the name. For example, if I were to have a .txt file containing these strings, Name: Shiroe Contact Number:...

Writing ArrayList of objects to textfile using filter

java,arraylist,filewriter
(Disclaimer: I am not done writing the coding, so I have been using lousy names to identify things.) I have an ArrayList of PersonObjects called PersonIndex. The parameters of the PersonObjects are as follows: Name, Age, Gender, Height. What I am trying to do is process the list and depending...

How to write data line by line from the two files into a common file in java

java,filewriter,separator
I am facing while merging two files in one (with common content) public class myFileReader { public static void main(String[] args) throws Exception { List<String> firstFileList = new ArrayList<String>(); List<String> secondFileList = new ArrayList<String>(); List<String> missingRecordsInFile2 = new ArrayList<String>(); Scanner firstFile = new Scanner(new FileReader(new File("C://write1.txt"))); Scanner secondFile = new...

Javascript and Cordova/Phonegap FileWriter gives Invalid_Modification_Error on a simple text file write

javascript,ios,cordova,text-files,filewriter
I am using Cordova File and FileTransfer plugins. I have the following permissions set in my config.xml <feature name="File"> <param name="ios-package" value="CDVFile" /> </feature> <feature name="FileTransfer"> <param name="ios-package" value="CDVFileTransfer" /> </feature> I am trying to write a plain text file using the following piece of code: this.writeFile = function (filename,...

log4j creates log file but does not write the messages that I am creating

java,logging,log4j,filewriter
Log file is getting created and logs are getting written into it.But , it doesn't write the things that i specify in LOG.trace("") and LOG.error("") etc. log4j.rootLogger=INFO,R # Direct log messages to stdout log4j.appender.stdout=org.apache.log4j.ConsoleAppender log4j.appender.stdout.Target=System.out log4j.appender.stdout.layout=org.apache.log4j.PatternLayout log4j.appender.stdout.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss}%-5p %c{1}:%L - %m%n log4j.appender.R=org.apache.log4j.RollingFileAppender...