Java using \034 as delimiter in a string

Question

I am trying to use '\034' field separator character as a delimiter in a string. The issue is when I hardcode "\034"+opField and write it to a file it works, but if the "\034" character is read from a file, it writes the output as string "col1\034col2'. I tried using StringBuilder but it escapes the \034 to "\\034". I am using the following code to read the character from the file:

try (BufferedReader br = new BufferedReader(new FileReader(fConfig))){
                int lc = 1;
                for(String line;(line = br.readLine())!=null;){
                    String[] rowList = line.split(delim); 
                    int row_len = rowList.length;
                    if (row_len<2){
                        System.out.println("Incorrect dictionary file row:"+fConfig.getAbsolutePath()+"\nNot enough values found at row:"+line);
                    }else{
                        String key = rowList[0];
                        String value = rowList[1];
                        dictKV.put(key, value);
                    }
                    lc++;
                }
            }catch(Exception e){
                throw e;
            }

Any help is welcome...

[update]: The same thing is happening with '\t' character, if harcoded fine, but if read from a file its getting appended as characters. "col0\tcol1"

if(colAl.toLowerCase().contains(" as ")){
                    String temp = colAl.replaceAll("[ ]+as[ ]+"," | ");
                    ArrayList<String> tempA = this.brittle_delim(temp,'|');
                    colAl = tempA.get(tempA.size()-1);
                    colAl = colAl.trim();
                }else {
                    ArrayList<String> tempA = this.brittle_delim(colAl,' ');
                    colAl = tempA.get(tempA.size()-1);
                    colAl = colAl.trim();
                }
                if(i==0){
                    sb.append(colAl);
                    headerCols+=colAl.trim();
                }else{
                    headerCols+= this.output_field_delim + colAl;
                    sb.append(this.output_field_delim);
                    sb.append(colAl);
                }

            }
        }

        System.out.println("SB Header Cols:"+sb.toString());
        System.out.println("Header Cols:"+headerCols);

Output:

SB Header Cols: SPRN_CO_ID\034FISC_YR_MTH_DSPLY_CD\034CST_OBJ_CD\034PRFT_CTR_CD\034LEGL_CO_CD\034HEAD_CT_TYPE_ID\034FIN_OWN_CD\034FUNC_AREA_CD\034HEAD_CT_NR

Header Cols: SPRN_CO_ID\034FISC_YR_MTH_DSPLY_CD\034CST_OBJ_CD\034PRFT_CTR_CD\034LEGL_CO_CD\034HEAD_CT_TYPE_ID\034FIN_OWN_CD\034FUNC_AREA_CD\034HEAD_CT_NR

In the above code if I do the following I am getting correct results:

headerCols+= "\034"+ colAl;

output: SPRN_CO_IDFISC_YR_MTH_DSPLY_CDCST_OBJ_CDPRFT_CTR_CDLEGL_CO_CDHEAD_CT_TYPE_IDFIN_OWN_CDFUNC_AREA_CDHEAD_CT_NR The FS characters are there even if they are geting removed here

You haven't posted the relevant code. You say "it writes the output as string "col1\034col2'." but you haven't included the code *that writes the output*! That code is most likely were the problem is (but it's probably not a problem, it's just a result of the way in which you write the output to the screen) — Erwin Bolwidt, Feb 24 '17 at 15:07
Can you give an example? I'm quite sure where that `col0\tcol1` would happen and what `col0` and `col1` are meant to be. — Thomas, Feb 24 '17 at 15:07
output_field_delim is coming from the above function and is being set in the constriuctor of this object. Its just a string assignment. — vhora, Feb 24 '17 at 15:17
You should replace `line.split(delim)` with `line.split(Pattern.quote(delim))` to avoid any surprises from split actually taking a regex. — David Ehrmann, Feb 24 '17 at 15:20
That doesnt seem to be the issue here as the delim will always be ";", but noted. Also the output_field_delim is correctly read as \034 which is what is stored in the file. — vhora, Feb 24 '17 at 15:23

score 0 · Answer 1 · answered Feb 24 '17 at 15:28

You should provide an example demonstrating your problem. Not just incomplete code snippets.

Following runable snippet does what you explained.

// create a file one line
byte[] bytes = "foo bar".getBytes(StandardCharsets.ISO_8859_1);
String fileName = "/tmp/foobar";
Files.write(Paths.get(fileName), bytes);

String headerCols = "";
String outputFieldDelim = "\034";
try (BufferedReader br = new BufferedReader(new FileReader(fileName))) {
    // read the line from the file and split by blank character
    String[] cols = br.readLine().split(" ");

    // contcatenate the values with "\034"
    // but ... for your code ...
    // don't concatenate String objects in a loop like below
    // use a StringBuilder or StringJoiner instead
    headerCols += outputFieldDelim + cols[0];
    headerCols += outputFieldDelim + cols[1];
}
// output with the "\034" character
System.out.println(headerCols);

Sorry if I wasn't clear. In my scenario I am reading the \034 from the file too, and that is where i am encountering the above problem. — vhora, Feb 24 '17 at 15:34
@vhora Then provide a small example which demonstrates the problem. Otherwise we can only guess what you actually do and what is in the file you read. — SubOptimal, Feb 24 '17 at 15:54
Thanks @SubOptimal , but the question was asked in a haphazard disarray at the end of a very long day. Thanks for your help anyways.. — vhora, Feb 24 '17 at 15:56

score 0 · Answer 2 · edited May 23 '17 at 12:09

0

I guess this is where I found my solution and the actual words for my Question.

How to unescape string literals in java

edited May 23 '17 at 12:09

Community

1
1

answered Feb 24 '17 at 15:52

vhora

320
2
16

Java using \034 as delimiter in a string

2 Answers2