ProgressHttpEntityWrapper.java

package communication;

import org.apache.http.HttpEntity;
import org.apache.http.entity.HttpEntityWrapper;

import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;

/**
 * Created by dv12csr on 2014-05-16.
 */

class ProgressHttpEntityWrapper extends HttpEntityWrapper {
    
    private final ProgressCallback progressCallback;
    
    public static interface ProgressCallback {
        public void progress(float progress);
    }
    
    public ProgressHttpEntityWrapper(final HttpEntity entity,
            final ProgressCallback progressCallback) {
        super(entity);
        this.progressCallback = progressCallback;
    }
    
    @Override
    public void writeTo(final OutputStream out) throws IOException {
        this.wrappedEntity.writeTo(out instanceof ProgressFilterOutputStream
                ? out : new ProgressFilterOutputStream(out,
                        this.progressCallback, getContentLength()));
    }
    
    static class ProgressFilterOutputStream extends FilterOutputStream {
        
        private long lastCheck;
        private final ProgressCallback progressCallback;
        private long transferred;
        private long totalBytes;
        
        ProgressFilterOutputStream(final OutputStream out,
                final ProgressCallback progressCallback, final long totalBytes) {
            super(out);
            this.progressCallback = progressCallback;
            this.transferred = 0;
            lastCheck = System.currentTimeMillis();
            this.totalBytes = totalBytes;
        }
        
        @Override
        public void write(final byte[] b, final int off, final int len)
                throws IOException {
            
            out.write(b, off, len);
            this.transferred += len;
            if (System.currentTimeMillis() - lastCheck > 1000) {
                this.progressCallback.progress(getCurrentProgress());
            }
        }
        
        @Override
        public void write(final int b) throws IOException {
            out.write(b);
            this.transferred++;
            this.progressCallback.progress(getCurrentProgress());
        }
        
        private float getCurrentProgress() {
            if (System.currentTimeMillis() - lastCheck > 1000) {
                return ((float) this.transferred / this.totalBytes) * 100;
            } else {
                return -1;
            }
        }
        
    }
    
}