BufferedWriter not writing everything to its output file
bufferedwriter, file-io, java
Solution
You need to close your `OutputStream` which will flush the remainder of your data:
out.close();
The default buffer size for `BufferedWriter` is 8192 characters, large enough to easily hold hundreds of lines of unwritten data.
Problem
I have a Java program that reads some text from a file, line by line, and writes new text to an output file. But not all the text I write to my `BufferedWriter` appears in the output file after the program has finished. Why is that? The details: the program takes a CSV text document and converts it into SQL commands to insert the data into a table. The text file has more than 10000 lines which look similar to following: ``` 2007,10,9,1,1,1006134,19423882 ``` The program seems to work fine except it just stops in the file randomly half way through creating a new SQL statement having printed it into the SQL file. It looks something like: ``` insert into nyccrash values (2007, 1, 2, 1, 4, 1033092, 259916); insert into nyccrash values (2007, 1, 1, 1, 1, 1020246, 197687); insert into nyccrash values (2007, 10, 9, 1 ``` This happens after about 10000 lines but several hundred lines before the end of the file. Where the break happens is between a `1` and a `,`. However, the characters doesn't seem important because if I change the `1` to a `42` the last thing written to the new file is `4`, which is cutting off the 2 from that integer. So it seems like the reader or writer must just be dying after writing/reading a certain amount. My Java code is as follows: ``` import java.io.*; public class InsertCrashData { public static void main (String args[]) { try { //Open the input file. FileReader istream = new FileReader("nyccrash.txt"); BufferedReader in = new BufferedReader(istream); //Open the output file. FileWriter ostream = new FileWriter("nyccrash.sql"); BufferedWriter out = new BufferedWriter(ostream); String line, sqlstr; sqlstr = "CREATE TABLE nyccrash (crash_year integer, accident_type integer, collision_type integer, weather_condition integer, light_condition integer, x_coordinate integer, y_coordinate integer);\n\n"; out.write(sqlstr); while((line = in.readLine())!= null) { String[] esa = line.split(","); sqlstr = "insert into nyccrash values ("+esa[0]+", "+esa[1]+", "+esa[2]+", "+esa[3]+", "+esa[4]+", "+esa[5]+", "+esa[6]+");\n"; out.write(sqlstr); } } catch(Exception e) { System.out.println(e); } } } ```