Java 去除文本文件多余的空格字符串

/**
     * 移除多余空行和空格
     */
    public static String dealRedundantSpaceAndBlankLine(String content) {
        if (content == null || content.length() == 0) {
            return "";
        }
        StringBuilder strAfterRemoveCRSB = new StringBuilder();
        for (int i = 0; i < content.length(); i++) {
            if (content.charAt(i) != '\r')
                strAfterRemoveCRSB.append(content.charAt(i));
        }
        String strAfterRemoveCR = strAfterRemoveCRSB.toString();
        if (strAfterRemoveCR == null || strAfterRemoveCR.length() == 0) {
            return "";
        }
        StringBuilder resultSB = new StringBuilder();
        String[] lines = strAfterRemoveCR.split("\n");
        int blankCount = 0;
        for (String line : lines) {
            if (line == null) {
                continue;
            }
            String lineTrim = line.trim();
            if ("".equals(lineTrim)) {
                blankCount++;
            } else {
                blankCount = 0;
                resultSB.append(dealSpace4OneLine(line));
            }
        }
        resultSB.deleteCharAt(resultSB.length() - 1);
        return resultSB.toString();
    }

    /**
     * 移除1行中的多余空格
     */
    public static String dealSpace4OneLine(String line) {
        if (line == null || "".equals(line)) {
            return "";
        }
        int spaceCount = 0;
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < line.length(); i++) {
            char curChar = line.charAt(i);
            if (curChar == ' ') {
                spaceCount++;
            } else {
                spaceCount = 0;
                sb.append(curChar);
            }
        }
        return sb.toString();
    }