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Java String.split alternative for better performance

In the process of adding import data from a split csv / tab file, my code takes a long time to load the data. Is there an alternative for this in a faster way? This is the code I am using to split the fields in an array.

 //Here -  lineString = fileReader.readLine()

public static String [] splitAndGetFieldNames(String lineString ,String fileType) 
{
    if(lineString==null || lineString.trim().equals("")){
        return null;
    }
    System.out.print("LINEEEE   " +  lineString);
    String pattern = "(?=(?:[^\"]*\"[^\"]*\")*(?![^\"]*\"))";
    if(fileType.equals("tab"))
        pattern = "\t" + pattern;
    else
        pattern = "," + pattern;

    String fieldNames[] = lineString.split(pattern);


    for(int i=0 ; i < fieldNames.length ; i++){
        //logger.info("Split Fields::"+fieldNames[i]);
        if (fieldNames[i].startsWith("\""))
            fieldNames[i] = fieldNames[i].substring(1);
        if (fieldNames[i].endsWith("\""))
            fieldNames[i] = fieldNames[i].substring(0, fieldNames[i].length()-1);
        fieldNames[i] = fieldNames[i].replaceAll("\"\"","\"").trim();
        //logger.info("Split Fields after manipulation::"+fieldNames[i]);
    }
    return fieldNames;
}
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2 answers


Use a CSV parser like super-csv .



Univocity provides a CSV parsers tag . It says univocity-parsers are fast, which isn't surprising. You may try.

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I would recommend you take a look at the opencsv library or try CSVParser fromApache Commons



In any case, reinventing the wheel is not a good idea. Using a third party library will be less of a headache than the writing itself :)

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