bundles/org.simantics.scl.rest/src/org/simantics/scl/rest/ReadProgressInterceptor.java

   1 package org.simantics.scl.rest;
   2
   3 import java.io.FilterInputStream;
   4 import java.io.IOException;
   5 import java.io.InputStream;
   6
   7 import javax.ws.rs.WebApplicationException;
   8 import javax.ws.rs.ext.ReaderInterceptor;
   9 import javax.ws.rs.ext.ReaderInterceptorContext;
  10
  11 import org.simantics.scl.runtime.function.Function1;
  12 import org.simantics.scl.runtime.tuple.Tuple0;
  13
  14 public class ReadProgressInterceptor implements ReaderInterceptor {
  15
  16     private Function1<Long, Tuple0> callback;
  17
  18     public ReadProgressInterceptor(Function1<Long, Tuple0> callback) {
  19         this.callback = callback;
  20     }
  21
  22     @Override
  23     public Object aroundReadFrom(ReaderInterceptorContext context) throws IOException, WebApplicationException {
  24
  25         final InputStream is = context.getInputStream();
  26
  27         context.setInputStream(new FilterInputStream(is) {
  28
  29             private long count;
  30
  31             @Override
  32             public int read(byte b[], int off, int len) throws IOException {
  33                 int read = in.read(b, off, len);
  34                 if (read > 0) {
  35                     count += read;
  36                     callback.apply(count);
  37                 }
  38                 return read;
  39             }
  40
  41             @Override
  42             public int read() throws IOException {
  43                 int read = in.read();
  44                 if (read > 0) {
  45                     count++;
  46                     callback.apply(count);
  47                 }
  48                 return read;
  49             }
  50         });
  51
  52         return context.proceed();
  53     }
  54
  55 }