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

   1 package org.simantics.scl.rest;
   2
   3 import java.io.FilterOutputStream;
   4 import java.io.IOException;
   5 import java.io.OutputStream;
   6
   7 import javax.ws.rs.WebApplicationException;
   8 import javax.ws.rs.ext.WriterInterceptor;
   9 import javax.ws.rs.ext.WriterInterceptorContext;
  10
  11 import org.simantics.scl.runtime.function.Function1;
  12 import org.simantics.scl.runtime.tuple.Tuple0;
  13
  14 public class WriteProgressInterceptor implements WriterInterceptor {
  15
  16     private Function1<Long, Tuple0> callback;
  17
  18     public WriteProgressInterceptor(Function1<Long, Tuple0> callback) {
  19         this.callback = callback;
  20     }
  21
  22     @Override
  23     public void aroundWriteTo(WriterInterceptorContext context) throws IOException, WebApplicationException {
  24
  25         final OutputStream os = context.getOutputStream();
  26
  27         context.setOutputStream(new FilterOutputStream(os) {
  28             private long count;
  29
  30             @Override public void write(byte[] b, int off, int len) throws IOException {
  31                 out.write(b, off, len);
  32                 count += len;
  33                 callback.apply(count);
  34             }
  35
  36             @Override
  37             public void write(int b) throws IOException {
  38                 out.write(b);
  39                 count++;
  40                 callback.apply(count);
  41             }
  42         });
  43
  44         context.proceed();
  45     }
  46
  47 }