將 Set 依指定分割符號轉回字串

//將  Set<String> 依指定分割符號轉回字串

public static String stringSetToStringWithSplitChar(Set<String> stringSet, String splitChar) throws Exception {

    String returnString = "";

    for (String key : stringSet) {

        if (returnString.length() > 0)

            returnString = returnString + splitChar + key;

        else {

            returnString = key;

        }

    }

    return returnString;

}

字串依分割符號轉為 Set

//將字串依分割符號轉成 Set<String>

public static Set<String> splitToStringSet(String sourceString, String splitChar) throws Exception {

    Set<String> stringSet = new HashSet<String>();

    String[] stringAry = sourceString.split(splitChar);

    for (int i = 0; i < stringAry.length; i++) {

        stringSet.add(stringAry[i]);

    }

    return stringSet;

}

字串陣列轉 Set

//String 陣列 --> Set<String>

public static Set<String> stringArrayToSet(String[] inputArray) throws Exception {

    Set<String> returnSet = new HashSet<String>();

    for (int i = 0; i < inputArray.length; i++) {

        returnSet.add(inputArray[i]);

    }

    return returnSet;

}

JAVA 讀檔並 return List

private static List<String> readFileToStringList(String filePath) {

    List<String> returnList = new ArrayList<String>();

    try {

        FileReader fr = new FileReader(filePath);

        BufferedReader br = new BufferedReader(fr);

        String line;

        while ((line = br.readLine()) != null) {

            System.out.println(line);

            returnList.add(line);

        }

    } catch (Exception e) {

        e.printStackTrace();

    }

    return returnList;

}

JAVA 遞迴走訪目錄

private void retrievalFolder(String path) throws Exception {

    try {

        File main = new File(path);

        if (main.isDirectory()) {

            String[] filename = main.list();

            for (int i = 0; i < filename.length; i++) {

                File sub = new File(main.getAbsoluteFile() + File.separator + filename[i]);

                if (sub.isDirectory()) {

                    this.retrievalFolder(main.getAbsoluteFile() + File.separator + filename[i]);

                } else {

                    //TODO

                }

            }

        } else {

            //TODO

        }

    } finally {

        //TODO

    }

}

可參考
列出目錄中(包含子目錄)之所有檔案