diff --git a/src/main/java/com/ning/http/client/providers/apache/ApacheResponse.java b/src/main/java/com/ning/http/client/providers/apache/ApacheResponse.java
index 9516f89ee4..2cdf19f629 100644
--- a/src/main/java/com/ning/http/client/providers/apache/ApacheResponse.java
+++ b/src/main/java/com/ning/http/client/providers/apache/ApacheResponse.java
@@ -35,13 +35,12 @@
 
 public class ApacheResponse implements Response {
     private final static String DEFAULT_CHARSET = "ISO-8859-1";
-    private final static String HEADERS_NOT_COMPUTED = "Response's headers hasn't been computed by your AsyncHandler.";
 
     private final URI uri;
     private final Collection<HttpResponseBodyPart> bodyParts;
     private final HttpResponseHeaders headers;
     private final HttpResponseStatus status;
-    private final List<Cookie> cookies = new ArrayList<Cookie>();
+    private List<Cookie> cookies;
 
     public ApacheResponse(HttpResponseStatus status,
                           HttpResponseHeaders headers,
@@ -77,21 +76,12 @@ public String getResponseBody() throws IOException {
     }
 
     public String getResponseBody(String charset) throws IOException {
-        String contentType = getContentType();
-        if (contentType != null && charset == null) {
-            charset = AsyncHttpProviderUtils.parseCharset(contentType);
-        }
-
-        if (charset == null) {
-            charset = DEFAULT_CHARSET;
-        }
-
-        return AsyncHttpProviderUtils.contentToString(bodyParts, charset);
+        return AsyncHttpProviderUtils.contentToString(bodyParts, computeCharset(charset));
     }
-
+    
     /* @Override */
     public InputStream getResponseBodyAsStream() throws IOException {
-        if (bodyParts.size() > 0) {
+        if (!bodyParts.isEmpty()) {
             return new HttpResponseBodyPartsInputStream(bodyParts.toArray(new HttpResponseBodyPart[bodyParts.size()]));
         } else {
             return new ByteArrayInputStream("".getBytes());
@@ -107,18 +97,22 @@ public String getResponseBodyExcerpt(int maxLength) throws IOException {
     /* @Override */
 
     public String getResponseBodyExcerpt(int maxLength, String charset) throws IOException {
-        String contentType = getContentType();
-        if (contentType != null && charset == null) {
-            charset = AsyncHttpProviderUtils.parseCharset(contentType);
-        }
-
-        if (charset == null) {
-            charset = DEFAULT_CHARSET;
-        }
+        charset = computeCharset(charset);
 
         String response = AsyncHttpProviderUtils.contentToString(bodyParts, charset);
         return response.length() <= maxLength ? response : response.substring(0, maxLength);
     }
+    
+    private String computeCharset(String charset) {
+    	String contentType = getContentType();
+        if (charset == null) {
+        	if (contentType != null)
+        		charset = AsyncHttpProviderUtils.parseCharset(contentType);
+        	else
+        		charset = DEFAULT_CHARSET;
+        }
+        return charset;
+    }
 
     /* @Override */
 
@@ -129,37 +123,25 @@ public URI getUri() throws MalformedURLException {
     /* @Override */
 
     public String getContentType() {
-        if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
-        }
-        return headers.getHeaders().getFirstValue("Content-Type");
+        return getHeader("Content-Type");
     }
 
     /* @Override */
 
     public String getHeader(String name) {
-        if (headers == null) {
-            throw new IllegalStateException();
-        }
-        return headers.getHeaders().getFirstValue(name);
+        return headers != null? headers.getHeaders().getFirstValue(name): null;
     }
 
     /* @Override */
 
     public List<String> getHeaders(String name) {
-        if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
-        }
-        return headers.getHeaders().get(name);
+        return headers != null? headers.getHeaders().get(name): Collections.<String> emptyList();
     }
 
     /* @Override */
 
     public FluentCaseInsensitiveStringsMap getHeaders() {
-        if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
-        }
-        return headers.getHeaders();
+        return headers != null? headers.getHeaders(): new FluentCaseInsensitiveStringsMap();
     }
 
     /* @Override */
@@ -172,21 +154,23 @@ public boolean isRedirected() {
 
     public List<Cookie> getCookies() {
         if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
+            return Collections.emptyList();
         }
-        if (cookies.isEmpty()) {
+        if (cookies == null) {
+        	List<Cookie> localCookies = new ArrayList<Cookie>();
             for (Map.Entry<String, List<String>> header : headers.getHeaders().entrySet()) {
                 if (header.getKey().equalsIgnoreCase("Set-Cookie")) {
                     // TODO: ask for parsed header
                     List<String> v = header.getValue();
                     for (String value : v) {
                         Cookie cookie = AsyncHttpProviderUtils.parseCookie(value);
-                        cookies.add(cookie);
+                        localCookies.add(cookie);
                     }
                 }
             }
+            cookies = Collections.unmodifiableList(localCookies);
         }
-        return Collections.unmodifiableList(cookies);
+        return cookies;
     }
 
     /**
@@ -194,7 +178,7 @@ public List<Cookie> getCookies() {
      */
     /* @Override */
     public boolean hasResponseStatus() {
-        return (bodyParts != null ? true : false);
+        return bodyParts != null;
     }
 
     /**
@@ -202,7 +186,7 @@ public boolean hasResponseStatus() {
      */
     /* @Override */
     public boolean hasResponseHeaders() {
-        return (headers != null ? true : false);
+        return headers != null;
     }
 
     /**
@@ -210,6 +194,6 @@ public boolean hasResponseHeaders() {
      */
     /* @Override */
     public boolean hasResponseBody() {
-        return (bodyParts != null && bodyParts.size() > 0 ? true : false);
+        return bodyParts != null && !bodyParts.isEmpty();
     }
 }
diff --git a/src/main/java/com/ning/http/client/providers/grizzly/GrizzlyResponse.java b/src/main/java/com/ning/http/client/providers/grizzly/GrizzlyResponse.java
index 52f3fece36..1f0b52784d 100644
--- a/src/main/java/com/ning/http/client/providers/grizzly/GrizzlyResponse.java
+++ b/src/main/java/com/ning/http/client/providers/grizzly/GrizzlyResponse.java
@@ -257,7 +257,7 @@ public List<Cookie> getCookies() {
                 cookies = convertCookies(builder.build());
 
             } else {
-                cookies = Collections.unmodifiableList(Collections.<Cookie>emptyList());
+                cookies = Collections.emptyList();
             }
         }
         return cookies;
diff --git a/src/main/java/com/ning/http/client/providers/jdk/JDKResponse.java b/src/main/java/com/ning/http/client/providers/jdk/JDKResponse.java
index f1fd4d2ce1..36700fde8d 100644
--- a/src/main/java/com/ning/http/client/providers/jdk/JDKResponse.java
+++ b/src/main/java/com/ning/http/client/providers/jdk/JDKResponse.java
@@ -36,13 +36,12 @@
 
 public class JDKResponse implements Response {
     private final static String DEFAULT_CHARSET = "ISO-8859-1";
-    private final static String HEADERS_NOT_COMPUTED = "Response's headers hasn't been computed by your AsyncHandler.";
 
     private final URI uri;
     private final Collection<HttpResponseBodyPart> bodyParts;
     private final HttpResponseHeaders headers;
     private final HttpResponseStatus status;
-    private final List<Cookie> cookies = new ArrayList<Cookie>();
+    private List<Cookie> cookies;
     private AtomicBoolean contentComputed = new AtomicBoolean(false);
     private String content;
 
@@ -81,28 +80,20 @@ public byte[] getResponseBodyAsBytes() throws IOException {
     }
 
     public String getResponseBody(String charset) throws IOException {
-        String contentType = getContentType();
-        if (contentType != null && charset == null) {
-            charset = AsyncHttpProviderUtils.parseCharset(contentType);
-        }
-
-        if (charset == null) {
-            charset = DEFAULT_CHARSET;
-        }
 
-        if (!contentComputed.get()) {
-            content = AsyncHttpProviderUtils.contentToString(bodyParts, charset);
+    	if (!contentComputed.get()) {
+            content = AsyncHttpProviderUtils.contentToString(bodyParts, computeCharset(charset));
         }
         return content;
     }
-
+    
     /* @Override */
     public InputStream getResponseBodyAsStream() throws IOException {
         if (contentComputed.get()) {
             return new ByteArrayInputStream(content.getBytes(DEFAULT_CHARSET));
         }
 
-        if (bodyParts.size() > 0) {
+        if (!bodyParts.isEmpty()) {
             return new HttpResponseBodyPartsInputStream(bodyParts.toArray(new HttpResponseBodyPart[bodyParts.size()]));
         } else {
             return new ByteArrayInputStream("".getBytes());
@@ -116,14 +107,7 @@ public String getResponseBodyExcerpt(int maxLength) throws IOException {
     }
 
     public String getResponseBodyExcerpt(int maxLength, String charset) throws IOException {
-        String contentType = getContentType();
-        if (contentType != null && charset == null) {
-            charset = AsyncHttpProviderUtils.parseCharset(contentType);
-        }
-
-        if (charset == null) {
-            charset = DEFAULT_CHARSET;
-        }
+        charset = computeCharset(charset);
 
         if (!contentComputed.get()) {
             content = AsyncHttpProviderUtils.contentToString(bodyParts, charset == null ? DEFAULT_CHARSET : charset);
@@ -131,6 +115,17 @@ public String getResponseBodyExcerpt(int maxLength, String charset) throws IOExc
 
         return content.length() <= maxLength ? content : content.substring(0, maxLength);
     }
+    
+    private String computeCharset(String charset) {
+    	String contentType = getContentType();
+        if (charset == null) {
+        	if (contentType != null)
+        		charset = AsyncHttpProviderUtils.parseCharset(contentType);
+        	else
+        		charset = DEFAULT_CHARSET;
+        }
+        return charset;
+    }
 
     /* @Override */
 
@@ -141,37 +136,25 @@ public URI getUri() throws MalformedURLException {
     /* @Override */
 
     public String getContentType() {
-        if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
-        }
-        return headers.getHeaders().getFirstValue("Content-Type");
+        return getHeader("Content-Type");
     }
 
     /* @Override */
 
     public String getHeader(String name) {
-        if (headers == null) {
-            throw new IllegalStateException();
-        }
-        return headers.getHeaders().getFirstValue(name);
+        return headers != null? headers.getHeaders().getFirstValue(name): null;
     }
 
     /* @Override */
 
     public List<String> getHeaders(String name) {
-        if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
-        }
-        return headers.getHeaders().get(name);
+        return headers != null? headers.getHeaders().get(name): Collections.<String> emptyList();
     }
 
     /* @Override */
 
     public FluentCaseInsensitiveStringsMap getHeaders() {
-        if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
-        }
-        return headers.getHeaders();
+        return headers != null? headers.getHeaders(): new FluentCaseInsensitiveStringsMap();
     }
 
     /* @Override */
@@ -184,21 +167,23 @@ public boolean isRedirected() {
 
     public List<Cookie> getCookies() {
         if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
+            return Collections.emptyList();
         }
         if (cookies.isEmpty()) {
+        	List<Cookie> localCookies = new ArrayList<Cookie>();
             for (Map.Entry<String, List<String>> header : headers.getHeaders().entrySet()) {
                 if (header.getKey().equalsIgnoreCase("Set-Cookie")) {
                     // TODO: ask for parsed header
                     List<String> v = header.getValue();
                     for (String value : v) {
                         Cookie cookie = AsyncHttpProviderUtils.parseCookie(value);
-                        cookies.add(cookie);
+                        localCookies.add(cookie);
                     }
                 }
             }
+            cookies = Collections.unmodifiableList(localCookies);
         }
-        return Collections.unmodifiableList(cookies);
+        return cookies;
     }
 
     /**
@@ -206,7 +191,7 @@ public List<Cookie> getCookies() {
      */
     /* @Override */
     public boolean hasResponseStatus() {
-        return (bodyParts != null ? true : false);
+        return bodyParts != null;
     }
 
     /**
@@ -214,7 +199,7 @@ public boolean hasResponseStatus() {
      */
     /* @Override */
     public boolean hasResponseHeaders() {
-        return (headers != null ? true : false);
+        return headers != null;
     }
 
     /**
@@ -222,6 +207,6 @@ public boolean hasResponseHeaders() {
      */
     /* @Override */
     public boolean hasResponseBody() {
-        return (bodyParts != null && bodyParts.size() > 0 ? true : false);
+        return bodyParts != null && !bodyParts.isEmpty();
     }
 }
diff --git a/src/main/java/com/ning/http/client/providers/netty/NettyResponse.java b/src/main/java/com/ning/http/client/providers/netty/NettyResponse.java
index 5af231d626..01c61d0165 100644
--- a/src/main/java/com/ning/http/client/providers/netty/NettyResponse.java
+++ b/src/main/java/com/ning/http/client/providers/netty/NettyResponse.java
@@ -41,13 +41,12 @@
  */
 public class NettyResponse implements Response {
     private final static String DEFAULT_CHARSET = "ISO-8859-1";
-    private final static String HEADERS_NOT_COMPUTED = "Response's headers hasn't been computed by your AsyncHandler.";
 
     private final URI uri;
     private final Collection<HttpResponseBodyPart> bodyParts;
     private final HttpResponseHeaders headers;
     private final HttpResponseStatus status;
-    private final List<Cookie> cookies = new ArrayList<Cookie>();
+    private List<Cookie> cookies;
 
     public NettyResponse(HttpResponseStatus status,
                          HttpResponseHeaders headers,
@@ -82,16 +81,7 @@ public String getResponseBody() throws IOException {
     }
 
     public String getResponseBody(String charset) throws IOException {
-        String contentType = getContentType();
-        if (contentType != null && charset == null) {
-            charset = AsyncHttpProviderUtils.parseCharset(contentType);
-        }
-
-        if (charset == null) {
-            charset = DEFAULT_CHARSET;
-        }
-
-        return AsyncHttpProviderUtils.contentToString(bodyParts, charset);
+        return AsyncHttpProviderUtils.contentToString(bodyParts, computeCharset(charset));
     }
 
     /* @Override */
@@ -116,17 +106,19 @@ public String getResponseBodyExcerpt(int maxLength) throws IOException {
     }
 
     public String getResponseBodyExcerpt(int maxLength, String charset) throws IOException {
-        String contentType = getContentType();
-        if (contentType != null && charset == null) {
-            charset = AsyncHttpProviderUtils.parseCharset(contentType);
-        }
-
+        String response = AsyncHttpProviderUtils.contentToString(bodyParts, computeCharset(charset));
+        return response.length() <= maxLength ? response : response.substring(0, maxLength);
+    }
+    
+    private String computeCharset(String charset) {
+    	String contentType = getContentType();
         if (charset == null) {
-            charset = DEFAULT_CHARSET;
+        	if (contentType != null)
+        		charset = AsyncHttpProviderUtils.parseCharset(contentType);
+        	else
+        		charset = DEFAULT_CHARSET;
         }
-
-        String response = AsyncHttpProviderUtils.contentToString(bodyParts, charset);
-        return response.length() <= maxLength ? response : response.substring(0, maxLength);
+        return charset;
     }
 
     /* @Override */
@@ -138,37 +130,25 @@ public URI getUri() throws MalformedURLException {
     /* @Override */
 
     public String getContentType() {
-        if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
-        }
-        return headers.getHeaders().getFirstValue("Content-Type");
+        return getHeader("Content-Type");
     }
 
     /* @Override */
 
     public String getHeader(String name) {
-        if (headers == null) {
-            throw new IllegalStateException();
-        }
-        return headers.getHeaders().getFirstValue(name);
+        return headers != null? headers.getHeaders().getFirstValue(name): null;
     }
 
     /* @Override */
 
     public List<String> getHeaders(String name) {
-        if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
-        }
-        return headers.getHeaders().get(name);
+        return headers != null? headers.getHeaders().get(name): Collections.<String> emptyList();
     }
 
     /* @Override */
 
     public FluentCaseInsensitiveStringsMap getHeaders() {
-        if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
-        }
-        return headers.getHeaders();
+        return headers != null? headers.getHeaders(): new FluentCaseInsensitiveStringsMap();
     }
 
     /* @Override */
@@ -181,21 +161,23 @@ public boolean isRedirected() {
 
     public List<Cookie> getCookies() {
         if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
+            return Collections.emptyList();
         }
-        if (cookies.isEmpty()) {
+        if (cookies == null) {
+        	List<Cookie> localCookies = new ArrayList<Cookie>();
             for (Map.Entry<String, List<String>> header : headers.getHeaders().entrySet()) {
                 if (header.getKey().equalsIgnoreCase("Set-Cookie")) {
                     // TODO: ask for parsed header
                     List<String> v = header.getValue();
                     for (String value : v) {
                         Cookie cookie = AsyncHttpProviderUtils.parseCookie(value);
-                        cookies.add(cookie);
+                        localCookies.add(cookie);
                     }
                 }
             }
+            cookies = Collections.unmodifiableList(localCookies);
         }
-        return Collections.unmodifiableList(cookies);
+        return cookies;
     }
 
     /**
@@ -203,7 +185,7 @@ public List<Cookie> getCookies() {
      */
     /* @Override */
     public boolean hasResponseStatus() {
-        return (status != null ? true : false);
+        return status != null;
     }
 
     /**
@@ -211,7 +193,7 @@ public boolean hasResponseStatus() {
      */
     /* @Override */
     public boolean hasResponseHeaders() {
-        return (headers != null ? true : false);
+        return headers != null;
     }
 
     /**
@@ -219,7 +201,7 @@ public boolean hasResponseHeaders() {
      */
     /* @Override */
     public boolean hasResponseBody() {
-        return (bodyParts != null && bodyParts.size() > 0 ? true : false);
+        return bodyParts != null && !bodyParts.isEmpty();
     }
 
 }