一、HttpServletRequestWrapper
在攔截器或springMvc等流的方式讀取Request的參數,由於只能使用一次,所以我這裏記錄了對Request的代理類,以便多次使用。
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.nio.charset.Charset;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
public class HttpServletRequestWrapper extends HttpServletRequestWrapper
{
private final byte[] body;
public HttpServletRequestWrapper(HttpServletRequest request) throws IOException
{
super(request);
ServletInputStream stream = request.getInputStream();
String requestBody = StreamUtils.copyToString(stream, Charset.forName("UTF-8"));
body = requestBody.getBytes("UTF-8");
}
@Override
public ServletInputStream getInputStream() throws IOException
{
final ByteArrayInputStream bais = new ByteArrayInputStream(body);
return new ServletInputStream()
{
@Override
public int read() throws IOException
{
return bais.read();
}
};
}
}
使用該代理類
// 解決Controller中RequestBody流的二次讀取
ServletRequest requestWrapper = new HttpServletRequestWrapper(httpRequest);
// 獲取流中的請求參數
Object params = getBodyString(requestWrapper);
getBodyString讀取數據流
private 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();
}
二、 ResponseWrapper
實現對Response的代理,能在響應結果中加入自己想其他返回的內容。
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpServletResponseWrapper;
public class ResponseWrapper extends HttpServletResponseWrapper
{
private ByteArrayOutputStream buffer;
private ServletOutputStream out;
public ResponseWrapper(HttpServletResponse response)
{
super(response);
buffer = new ByteArrayOutputStream();
out = new WrapperOutputStream(buffer);
}
@Override
public ServletOutputStream getOutputStream() throws IOException
{
return out;
}
@Override
public void flushBuffer() throws IOException
{
if (out != null)
{
out.flush();
}
}
public byte[] getContent() throws IOException
{
flushBuffer();
return buffer.toByteArray();
}
class WrapperOutputStream extends ServletOutputStream
{
private ByteArrayOutputStream bos;
public WrapperOutputStream(ByteArrayOutputStream bos)
{
this.bos = bos;
}
@Override
public void write(int b) throws IOException
{
bos.write(b);
}
}
}
使用response代理類
// 轉換成代理類
ResponseWrapper wrapperResponse = new ResponseWrapper((HttpServletResponse)servletResponse);
// 這裏只攔截返回,直接讓請求過去,如果在請求前有處理,可以在這裏處理
chain.doFilter(requestWrapper, wrapperResponse);
byte[] content = wrapperResponse.getContent();// 獲取返回值
String result = null;
// 判斷是否有值
if (null != content)
{
result = new String(content, "UTF-8");
// 把返回值輸出到客戶端
ServletOutputStream out = servletResponse.getOutputStream();
out.write(result.getBytes());
out.flush();
}