diff --git a/graphql-java-servlet/src/main/java/graphql/kickstart/servlet/BatchedQueryResponseWriter.java b/graphql-java-servlet/src/main/java/graphql/kickstart/servlet/BatchedQueryResponseWriter.java
index bfa669a4..0cfcb733 100644
--- a/graphql-java-servlet/src/main/java/graphql/kickstart/servlet/BatchedQueryResponseWriter.java
+++ b/graphql-java-servlet/src/main/java/graphql/kickstart/servlet/BatchedQueryResponseWriter.java
@@ -33,8 +33,9 @@ public void write(HttpServletRequest request, HttpServletResponse response) thro
     responseBuilder.append(']');
 
     String responseContent = responseBuilder.toString();
-    response.setContentLength(responseContent.getBytes(StandardCharsets.UTF_8).length);
-    response.getWriter().write(responseContent);
+    byte[] contentBytes = responseContent.getBytes(StandardCharsets.UTF_8);
+    response.setContentLength(contentBytes.length);
+    response.getOutputStream().write(contentBytes);
   }
 
 }
diff --git a/graphql-java-servlet/src/main/java/graphql/kickstart/servlet/SingleQueryResponseWriter.java b/graphql-java-servlet/src/main/java/graphql/kickstart/servlet/SingleQueryResponseWriter.java
index 417cad69..fa166d3e 100644
--- a/graphql-java-servlet/src/main/java/graphql/kickstart/servlet/SingleQueryResponseWriter.java
+++ b/graphql-java-servlet/src/main/java/graphql/kickstart/servlet/SingleQueryResponseWriter.java
@@ -21,8 +21,9 @@ public void write(HttpServletRequest request, HttpServletResponse response) thro
     response.setStatus(HttpRequestHandler.STATUS_OK);
     response.setCharacterEncoding(StandardCharsets.UTF_8.name());
     String responseContent = graphQLObjectMapper.serializeResultAsJson(result);
-    response.setContentLength(responseContent.getBytes(StandardCharsets.UTF_8).length);
-    response.getWriter().write(responseContent);
+    byte[] contentBytes = responseContent.getBytes(StandardCharsets.UTF_8);
+    response.setContentLength(contentBytes.length);
+    response.getOutputStream().write(contentBytes);
   }
 
 }
diff --git a/graphql-java-servlet/src/test/groovy/graphql/kickstart/servlet/SingleQueryResponseWriterTest.groovy b/graphql-java-servlet/src/test/groovy/graphql/kickstart/servlet/SingleQueryResponseWriterTest.groovy
index 4c7a6ca9..ae834c19 100644
--- a/graphql-java-servlet/src/test/groovy/graphql/kickstart/servlet/SingleQueryResponseWriterTest.groovy
+++ b/graphql-java-servlet/src/test/groovy/graphql/kickstart/servlet/SingleQueryResponseWriterTest.groovy
@@ -7,8 +7,10 @@ import org.codehaus.groovy.runtime.StringBufferWriter
 import spock.lang.Specification
 import spock.lang.Unroll
 
+import javax.servlet.ServletOutputStream
 import javax.servlet.http.HttpServletRequest
 import javax.servlet.http.HttpServletResponse
+import java.nio.charset.StandardCharsets
 
 class SingleQueryResponseWriterTest extends Specification {
 
@@ -20,18 +22,16 @@ class SingleQueryResponseWriterTest extends Specification {
 
       def requestMock = Mock(HttpServletRequest)
       def responseMock = Mock(HttpServletResponse)
+      responseMock.getOutputStream() >> Mock(ServletOutputStream)
 
-      def responseContentBuffer = new StringBuffer()
-      responseMock.getWriter() >> new PrintWriter(new StringBufferWriter(responseContentBuffer))
       1 * responseMock.setContentLength(expectedContentLenght)
-      1 * responseMock.setCharacterEncoding("UTF-8")
+      1 * responseMock.setCharacterEncoding(StandardCharsets.UTF_8.name())
+      1 * responseMock.getOutputStream().write(expectedResponseContent.getBytes(StandardCharsets.UTF_8))
 
     expect:
       def writer = new SingleQueryResponseWriter(new ExecutionResultImpl(result, []), graphQLObjectMapperMock)
       writer.write(requestMock, responseMock)
 
-      responseContentBuffer.toString() == expectedResponseContent
-
     where:
       result                || expectedContentLenght | expectedResponseContent
       [testValue: "abcde"]  || 30                    | """{"data":{"testValue":"abcde"}}"""