Java中csv文件的正则表达式

Question

我必须从 CSV 文件中找出符合特定搜索条件的行。 CSV 文件中的数据如下所示：

Wilbur Smith,Elephant Song,McMillain,1992,1
Wilbur Smith,Birds of Prey,McMillain,1992,1
George Orwell,Animal Farm,Secker & Warburg,1945,1
George Orwell,1984,Secker & Warburg,1949,1

搜索条件是这样的：

Orwell,,,,
,Elephant,,,

第一行标识 2 行，第二行标识 1 行。我目前正在按如下方式读取文件，但未使用上述标准。

br = new BufferedReader(new FileReader(csvFile));
while ((line = br.readLine()) != null) {
    String[] dataItems = line.split(cvsSplitBy);

    if (dataItems[0].contains(title) && dataItems[1].contains(author) && dataItems[2].contains(publisher)) {
        bk[i++] = line;
        if (bk.length > 4) {break;}
    }
}

我正在添加一个固定大小的数组。如何使用条件作为正则表达式来识别行？

Answer 1

似乎我在这里是少数 :) 但如果您有兴趣，这里有一个使用正则表达式的版本。

BufferedReader br = null;

String[] searches = new String[]{
            ",Animal Farm,Secker & Warburg,,",
            ",,Secker & Warburg,,",
            "George Orwell,,,,1",
            "Wilbur Smith,,,,",
            ",,,,1",
            "random,,,,1",
            "WILBUR SMITH,Birds of PREY,mcmillain,1992,1",
            ",,,,"
};

try {
    br = new BufferedReader(new FileReader("file.txt"));
    String line = null;

    // to store results of matches for easier output
    String[] matchResult = new String[searches.length];

    while ((line = br.readLine()) != null) {
        // go through all searches
        for (int i = 0; i < searches.length; i++) {

            /*
             *  replace all commas that don't have letters or numbers on both 
             *  sides with a new regex to match all characters
             */
            String searchPattern = searches[i].replaceAll("(?<![a-zA-z0-9])\\,|\\,(?![a-zA-z0-9\\,])", ".*,.*");

            // do the match on the line
            Matcher m = Pattern.compile("^" + searchPattern + "$", Pattern.CASE_INSENSITIVE).matcher(line);

            // store the result
            matchResult[i] = m.matches() == true ? "matches" : "no match";
        }

        System.out.println(String.format("%-50s %-10s %-10s %-10s %-10s %-10s %-10s %-10s", line, 
                    matchResult[0], matchResult[1], matchResult[2], matchResult[3], matchResult[4], matchResult[5], matchResult[6], matchResult[7]));
    }
} catch (Exception e) {
        e.printStackTrace();
} finally {
    try {
        br.close();
    } catch (IOException e) {}
}

输出

Wilbur Smith,Elephant Song,McMillain,1992,1        no match   no match   no match   matches    matches    no match   no match  
Wilbur Smith,Birds of Prey,McMillain,1992,1        no match   no match   no match   matches    matches    no match   matches   
George Orwell,Animal Farm,Secker & Warburg,1945,1  matches    matches    matches    no match   matches    no match   no match  
George Orwell,1984,Secker & Warburg,1949,1         no match   matches    matches    no match   matches    no match   no match