自定義過濾器（Filter）, 獲取返回值
public class ResponseWrapper extends HttpServletResponseWrapper {
private ByteArrayOutputStream buffer;
private ServletOutputStream out;
public ResponseWrapper(HttpServletResponse httpServletResponse) {
super(httpServletResponse);
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);
}
@Override
public boolean isReady() {
return false;
}
@Override
public void setWriteListener(WriteListener arg0) {
}
}
自定義過濾器類CustomFilter實現Filter接口；
public class CustomFilter implements Filter {
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
ResponseWrapper wrapperResponse = new ResponseWrapper((HttpServletResponse)response);
chain.doFilter(request, wrapperResponse);
byte[] content = wrapperResponse.getContent();
if(content.length > 0) {
String str = new String(content, "UTF-8");
JsonObject fromJson = new Gson().fromJson(str, JsonObject.class);
if(fromJson.get("status").toString().equals("200")) {
//do something
}
}
}
@Override
public void destroy() {
}