StringBuffer不能完全读取

Question

我有一个简单的函数，用于连接到服务器并以字符串形式返回响应。当返回的数据量很小，但响应量很大时，它工作得很好。它不会完全存储服务器返回的响应字符串，并以...结尾。令人惊讶的是，system.out.println返回正确的响应。请帮帮我。我真的卡住了。

protected String getResponseFromServer(String URLaddress) {

    HttpURLConnection connection = null;
    URL serverAddress = null;
    BufferedReader rd = null;
    StringBuffer sb = new StringBuffer();
    try {
        serverAddress = new URL(URLaddress);
        // set up out communications stuff
        connection = null;
        connection = (HttpURLConnection) serverAddress.openConnection();
        connection.setReadTimeout(20000);
        connection.connect();
        // read the result from the server
        rd = new BufferedReader(new InputStreamReader(
                connection.getInputStream()));
        String line;
        while ((line = rd.readLine()) != null) {
            System.out.print(line.trim());
            sb.append(line.trim());
        }

    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        // close the connection, set all objects to null
        connection.disconnect();
        connection = null;
    }
    return sb.toString();
}

Answer 1

您是否获得了被截断的字符串(以...结尾)当你调试的时候？在返回之前尝试System.out.println(sb.toString())；。

Answer 2

(编辑:此答案基于OP最初发布的代码。此后，OP已对该问题进行了编辑，以更改违规代码。)

这里有一个bug：

sb.append(line.trim(), 0, line.length());

如果line有任何前导空格或尾随空格，则line.length()将大于line.trim().length()。在本例中为sb.append() would throw IndexOutOfBoundsException

IndexOutOfBoundsException -如果start或end为负，或者start大于end，或者s.length()

大于