set some http headers in the response (fix #251)

src/main/java/com/commafeed/frontend/rest/JsonProvider.java

@@ -0,0 +1,34 @@
+package com.commafeed.frontend.rest;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.lang.annotation.Annotation;
+import java.lang.reflect.Type;
+
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.MultivaluedMap;
+import javax.ws.rs.ext.Provider;
+
+import org.apache.http.HttpHeaders;
+
+import com.fasterxml.jackson.jaxrs.json.JacksonJsonProvider;
+
+@Provider
+public class JsonProvider extends JacksonJsonProvider {
+
+	@Override
+	public void writeTo(Object value, Class<?> type, Type genericType,
+			Annotation[] annotations, MediaType mediaType,
+			MultivaluedMap<String, Object> httpHeaders,
+			OutputStream entityStream) throws IOException {
+
+		httpHeaders.putSingle(HttpHeaders.CONTENT_TYPE, mediaType.toString()
+				+ ";charset=UTF-8");
+		httpHeaders.putSingle(HttpHeaders.CACHE_CONTROL, "no-cache");
+		httpHeaders.putSingle(HttpHeaders.PRAGMA, "no-cache");
+
+		super.writeTo(value, type, genericType, annotations, mediaType,
+				httpHeaders, entityStream);
+	}
+
+}