Java8重写拼接文件除去文件头尾的各行

gistfile1.txt

    public static String loadPemKey(String fileName) throws Exception {
        // TODO： 可以考虑用Java8重写
        BufferedReader br = new BufferedReader(new FileReader(PATH + fileName));
        String s = br.readLine();
        String str = "";
        s = br.readLine();
        while (s.charAt(0) != '-') {
            //str += s + "\r";
            str+=s;
            s = br.readLine();
        }

        return str;
    }
    
        List<String> lines = Files.readAllLines(Paths.get("src/main/resources/privateKey/foo.pem"));
        String reduce = lines.stream().filter(line->!line.startsWith("-")).reduce("", (line1, line2) -> line1 + line2);

        String pemKey = TnGetSignUtil.loadPemKey("foo.pem");
        assertEquals(pemKey,reduce);
        
        // 更简洁
        String reduce = Files.lines(Paths.get(path)).filter(line->!line.startsWith("-")).collect(joining());