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解決request.getInputStream()只能讀取一次的問題

參考文章:http://dditblog.com/itshare_529.html

程式碼需要獲取入參裡面URL後面的引數,還有POST請求裡面BODY的資料;

1、直接獲取URL後面的資料

直接使用request.getParameter("appKey");就可以完成

2、獲取BODY裡面的JSON資料

無法直接獲取request,直接獲取getInputStream()裡面入參情況,遍歷的時候會提示streamclose()的錯誤;

造成原因:

request在Spring裡面已經獲取了一次,流只能讀一次、 讀了就沒有了、為了後面的程式碼還能夠取得流;

解決辦法:

/**
 * 獲取請求Body
 *
 * 
@param request * @return */ public static String getBodyString(ServletRequest request) { StringBuilder sb = new StringBuilder(); InputStream inputStream = null; BufferedReader reader = null; try { inputStream = request.getInputStream(); reader = new BufferedReader(new
InputStreamReader(inputStream, Charset.forName("UTF-8"))); String line = ""; while ((line = reader.readLine()) != null) { sb.append(line); } } catch (IOException e) { e.printStackTrace(); } finally { if (inputStream != null) {
try { inputStream.close(); } catch (IOException e) { e.printStackTrace(); } } if (reader != null) { try { reader.close(); } catch (IOException e) { e.printStackTrace(); } } } return sb.toString(); }
HttpHelper.java
@Override
protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
        throws ServletException, IOException {
            
    // 防止流讀取一次後就沒有了, 所以需要將流繼續寫出去
    ServletRequest requestWrapper = new BodyReaderHttpServletRequestWrapper(request);
    String json = HttpHelper.getBodyString(requestWrapper);
            
    System.out.println(json);

    filterChain.doFilter(requestWrapper, response);
}
Filter.Java
public class BodyReaderHttpServletRequestWrapper extends HttpServletRequestWrapper {

    private final byte[] body;

    public BodyReaderHttpServletRequestWrapper(HttpServletRequest request) throws IOException {
        super(request);
        body = HttpHelper.getBodyString(request).getBytes(Charset.forName("UTF-8"));
    }

    @Override
    public BufferedReader getReader() throws IOException {
        return new BufferedReader(new InputStreamReader(getInputStream()));
    }

    @Override
    public ServletInputStream getInputStream() throws IOException {

        final ByteArrayInputStream bais = new ByteArrayInputStream(body);

        return new ServletInputStream() {

            @Override
            public int read() throws IOException {
                return bais.read();
            }

            @Override
            public boolean isFinished() {
                return false;
            }

            @Override
            public boolean isReady() {
                return false;
            }

            @Override
            public void setReadListener(ReadListener readListener) {

            }
        };
    }

}
BodyReaderHttpServletRequestWrapper.java