I've run into a problem when trying to parse a JSON string that I grab from a file. My problem is that the Zero width no-break space character (unicode 0xfeff) is at the beginning of my string when I read it in, and I cannot get rid of it. I don't want to use regex because of the chance there may be other hidden characters with different unicodes.
Here's what I have:
StringBuilder content = new StringBuilder();
try {
BufferedReader br = new BufferedReader(new FileReader("src/test/resources/getStuff.json"));
String currentLine;
while((currentLine = br.readLine()) != null) {
content.append(currentLine);
}
br.close();
} catch(Exception e) {
Assert.fail();
}
And this is the the start of the JSON file (it's too long to copy paste the whole thing, but I have confirmed it is valid):
{"result":{"data":{"request":{"year":null,"timestamp":1413398641246,...
Here's what I've tried so far:
Copying the JSON file to notepad++ and showing all characters
Copying file to notepad++ and converting to UFT-8 without BOM, and ISO 8859-1
Opened JSON file in other text editors such as sublime and saved as UFT-8
Copied the JSON file to a txt file and read that in
Tried using Scanner instead of BufferedReader
In intellij I tried view -> active editor -> show whitespaces
How can I read this file in without having the Zero width no-break space character at the beginning of the string?
0xEF 0xBB 0xBF is the UTF-8 BOM, 0xFE 0xFF is the UTF-16BE BOM, and 0xFF 0xFE is the UTF-16LE BOM. If 0xFEFF exists at the front of your String, it means you created a UTF encoded text file with a BOM. A UTF-16 BOM could appear as-is as 0xFEFF, whereas a UTF-8 BOM would only appear as 0xFEFF if the BOM itself were being decoded from UTF-8 to UTF-16 (meaning the reader detected the BOM but did not skip it). In fact, it is known that Java does not handle UTF-8 BOMs (see bugs JDK-4508058 and JDK-6378911).
If you read the FileReader documentation, it says:
The constructors of this class assume that the default character encoding and the default byte-buffer size are appropriate. To specify these values yourself, construct an InputStreamReader on a FileInputStream.
You need to read the file content using a reader that recognizes charsets, preferably one that will read the BOM for you and adjust itself internally as needed. But worse case, you could just open the file yourself, read the first few bytes to detect if a BOM is present, and then construct a reader using an appropriate charset to read the rest of the file. Here is an example using org.apache.commons.io.input.BOMInputStream that does exactly that:
(from https://stackoverflow.com/a/13988345/65863)
String defaultEncoding = "UTF-8";
InputStream inputStream = new FileInputStream(someFileWithPossibleUtf8Bom);
try {
BOMInputStream bOMInputStream = new BOMInputStream(inputStream);
ByteOrderMark bom = bOMInputStream.getBOM();
String charsetName = bom == null ? defaultEncoding : bom.getCharsetName();
InputStreamReader reader = new InputStreamReader(new BufferedInputStream(bOMInputStream), charsetName);
//use reader
} finally {
inputStream.close();
}
Related
I have a problem with Java because I have a file with ASCII encoding and when I pass that value to the output file it changes special characters that I need to keep:
Original file:
Output file:
The code I use to read an ASCII file and pass it to a string that has a length of 7000 and the problem with that file where it reaches the special characters that within the frame or string that is the position 486 to 498 the FileRender does not bring the special characters correctly changes them for others and does not keep them (as I understand it is a binary):
fr = new FileReader(sourceFile);
//BufferedReader br = new BufferedReader(fr);
BufferedReader br = new BufferedReader(
new InputStreamReader(new FileInputStream(sourceFile), "UTF-8"));
String asciiString;
asciiString = br.readLine();
Edit:
I am doing a conversion from ASCII to EBCDIC. I am using CharFormatConverter.java
I really don't understand why the special characters are lost and not maintained. I found the UTF-8 code in another forum, but characters are still lost. Read file utf-8
Edit:
I was thinking about using FileReader for the ASCII data and FileInputStream to get the binary (but I can't figure out how to get it out with respect to the positions) that is in the ASCII file and thus have the two formats separated and then merge them after the conversion.
Regards.
If your info in the file is a binary info and not textual you can not read it as a String and no charset will help you. As charset is a schema that tells you how to interpret particular character into numeric code and vise-versa. If your info is not textual charset won't help you. You will need to read your info as binary - a sequence of bytes - and write them the same way. you will need to use InputStream implementation that reads info as binary. In your case a good candidate might be FileInputStream. But some other options may be used
Since your base code (CharFormatConverter) is byte-oriented, and it looks like your input files are binary, you should replace Readers by InputStreams, which produce bytes (not characters).
This is the ordinary way to read and process an InputStream:
private void convertFileToEbcdic(File sourceFile)
throws IOException
{
try (InputStream input=new FileInputStream(sourceFile))
{
byte[] buffer=new byte[4096];
int len;
do {
len=input.read(buffer);
if (len>0)
{
byte[] ebcdic=convertBufferFromAsciiToEbcdic(buffer, len);
// Now ebcdic contains the buffer converted to EBCDIC. You may use it.
}
} while (len>=0);
}
}
private byte[] convertBufferFromAsciiToEbcdic(byte[] ascii, int length)
{
// Create an array of same input as received
// and fill it with the input data converted to EBCDIC
}
I have a weird problem with files.
I intend to modify the timing of an .srt file, but writing the new file seems to be a weird task.
Here's a sample code I wrote:
import java.io.*;
import java.nio.charset.Charset;
public class ReaderWriter {
public static void main(String[] args) throws IOException {
InputStream inputStream = new FileInputStream("D:\\E\\Movies\\English\\1960's\\TheApartment1960.srt");
Reader reader = new InputStreamReader(inputStream,
Charset.forName("UTF-8"));
OutputStream outputStream = new FileOutputStream("output.srt");
Writer writer = new OutputStreamWriter(outputStream,
Charset.forName("UTF-8"));
int data = reader.read();
while (data != -1) {
char theChar = (char) data;
writer.write(theChar);
data = reader.read();
}
reader.close();
writer.close();
}
}
This is an image from the original file:
However, the resulted file seems like:
I searched a lot for a solution but in vain. Any help, please.
First a few points:
There is nothing wrong with your Java code. If I use it to read an input file containing Arabic text encoded in UTF-8 it creates the output file encoded in UTF-8 with no problems.
I don't think there is a font issue. Since you can successfully display the content of the input file there is no reason you cannot also successfully display the content of a valid output file.
Those black diamonds with question marks in the output file are replacement characters which are "used to replace an incoming character whose value is unknown or unrepresentable in Unicode". This indicates that the input file you are reading is not UTF-8 encoded, even though the code explicitly states that it is. I can reproduce similar results to yours if the input file is UTF-16 encoded, but specified as UTF-8 in the code.
Alternatively, if the input file truly is UTF-8 encoded, specify it as UTF-16 in the code. For example, here is a valid UTF-8 input file with some Arabic text where the code (incorrectly) stated Reader reader = new InputStreamReader(inputStream, Charset.forName("UTF-16"));:
يونكود في النظم القائمة وفيما يخص التطبيقات الحاسوبية، الخطوط، تصميم النصوص والحوسبة متعددة اللغات.
And here is the output file, containing the replacement characters because the input stream of the UTF-8 file was incorrectly processed as UTF-16:
���⃙臙訠���ꟙ蓙苘Ꟙꛙ藘ꤠ���諘께딠�����ꟙ蓘귘Ꟙ동裘꣙諘꧘谠����뗙藙諙蔠���⃙裘ꟙ蓘귙裘돘꣘ꤠ���⃘ꟙ蓙蓘뫘Ꟙꨮ�
Given all that, simply ensuring that the encoding of the input file is specified correctly in the InputStreamReader() constructor should solve your problem. To verify this, just create another input file and save it with UTF-8 character encoding, then run your code. If it works then you know that the problem was the that the encoding of input file was not UTF-8.
I have a file, when displayed with geanny * shows UTF-16BE. If I try to convert this file in Java to a different encoding (let's say ISO-8859-1), assuming it is UTF-16BE, a question mark (?) appears every time at the beginning of new created file. If instead I assume it is in UTF-16 (something that's not true), the converted file gets converted ok, without any question mark at the beginning.
Can anybody clarify why this behavior?
Bellow is a snippet from my used code:
StringBuilder sb = new StringBuilder();
BufferedReader buff = new BufferedReader(new InputStreamReader(inputStream, utf16beCharset));
String line = null;
while ( (line = buff.readLine()) != null) {
sb.append(line);
sb.append('\n');
}
String output = new String(sb.toString().getBytes(neededCharset), neededCharset);
System.out.println(output);
* geanny is a text editor
Your Problem is the BOM (Byte Order Mark).
If you define the character set as UTF-16 then Java recognises the BOM and removes it after reading. The BOM then tells Java that the character stream is (UTF-16)BE.
If you define UTF-16BE then you tell Java to ignore the BOM and Java ignores it and writes it to your target file.
I'm trying to read a file from the SD card and I've been told it's in unicode format. However, when I try to read the file I get the following:
This is the code I'm using to read the file:
InputStreamReader fw = new InputStreamReader(new FileInputStream(root.getAbsolutePath()+"/Drive/sdk/cmd.62.out"), "UTF-8");
char[] buf = new char[255];
fw.read(buf);
String readString = new String(buf);
Log.d("courierread",readString);
fw.close();
If I write that output to a file this is what I get when I open it in a hex editor:
Any thoughts on what I need to do to read the file correctly?
Does the file have a byte-order mark? In that case look at Reading UTF-8 - BOM marker
EDIT (from comment): That looks like little-endian UTF-16 to me. Try the charset "UTF-16LE".
The file you show in the hex editor is not UTF-8 encoded, it looks more like UTF-16. This means you must specify UTF-16 as the encoding in your code (probably the UTF-16LE variant).
If it were UTF-8 encoded, then it would represent all characters representable in ASCII using just a single byte.
I am using:
InputStreamReader isr = new InputStreamReader(fis, "UTF8");
to read in characters from a text file and converting them to UTF8 characters.
My question is, what if one of the characters being read cannot be converted to utf8, what happens? Will there be an exception? or will get the character get dropped off?
You are not converting from one charset to another. You are just indicating that the file is UTF 8 encoded so that you can read it correctly.
If you want to convert from 1 encoding to the other then you should do something like below
File infile = new File("x-utf8.txt");
File outfile = new File("x-utf16.txt");
String fromEncoding="UTF-8";
String toEncoding="UTF-16";
Reader in = new InputStreamReader(new FileInputStream(infile), fromEncoding);
Writer out = new OutputStreamWriter(new FileOutputStream(outfile), toEncoding);
After going through the David Gelhar's response, I feel this code can be improved a bit. If you doesn't know the encoding of the "inFile" then use the GuessEncoding library to detect the encoding and then construct the reader in the encoding detected.
If the input file contains bytes that are not valid utf-8, read() will by default replace the invalid characters with a value of U+FFFD (65533 decimal; the Unicode "replacement character").
If you need more control over this behavior, you can use:
InputStreamReader(InputStream in, CharsetDecoder dec)
and supply a CharsetDecoder configured to your liking.