Fix proposal for AsyncHttpClient#182 against master

Author: Stephane Landelle

api/src/main/java/com/ning/http/client/providers/ResponseBase.java

@@ -15,7 +15,6 @@
 public abstract class ResponseBase implements Response
 {
     protected final static String DEFAULT_CHARSET = "ISO-8859-1";
-    protected final static String HEADERS_NOT_COMPUTED = "Response's headers hasn't been computed by your AsyncHandler.";
 
     protected final List<HttpResponseBodyPart> bodyParts;
     protected final HttpResponseHeaders headers;
@@ -48,25 +47,22 @@ public final URI getUri() /*throws MalformedURLException*/ {
 
     /* @Override */
     public final String getContentType() {
-        return getHeader("Content-Type");
+        return headers != null? getHeader("Content-Type"): null;
     }
 
     /* @Override */
     public final String getHeader(String name) {
-        return getHeaders().getFirstValue(name);
+        return headers != null? getHeaders().getFirstValue(name): null;
     }
 
     /* @Override */
     public final List<String> getHeaders(String name) {
-        return getHeaders().get(name);
+        return headers != null? getHeaders().get(name): null;
     }
 
     /* @Override */
     public final FluentCaseInsensitiveStringsMap getHeaders() {
-        if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
-        }
-        return headers.getHeaders();
+        return headers != null? headers.getHeaders(): new FluentCaseInsensitiveStringsMap();
     }
 
     /* @Override */

api/src/main/java/com/ning/http/client/providers/jdk/JDKResponse.java

@@ -13,7 +13,6 @@
 package com.ning.http.client.providers.jdk;
 
 import com.ning.http.client.Cookie;
-import com.ning.http.client.FluentCaseInsensitiveStringsMap;
 import com.ning.http.client.HttpResponseBodyPart;
 import com.ning.http.client.HttpResponseHeaders;
 import com.ning.http.client.HttpResponseStatus;
@@ -50,7 +49,7 @@ public String getResponseBodyExcerpt(int maxLength, String charset) throws IOExc
     /* @Override */
     public List<Cookie> getCookies() {
         if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
+            return Collections.emptyList();
         }
         if (cookies.isEmpty()) {
             for (Map.Entry<String, List<String>> header : headers.getHeaders().entrySet()) {

providers/apache/src/main/java/com/ning/http/client/providers/apache/ApacheResponse.java

@@ -26,7 +26,6 @@
 import java.util.Map;
 
 public class ApacheResponse extends ResponseBase {
-    private final static String HEADERS_NOT_COMPUTED = "Response's headers hasn't been computed by your AsyncHandler.";
 
     private final List<Cookie> cookies = new ArrayList<Cookie>();
 
@@ -61,7 +60,7 @@ public String getResponseBodyExcerpt(int maxLength, String charset) throws IOExc
     /* @Override */
     public List<Cookie> getCookies() {
         if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
+            return Collections.emptyList();
         }
         if (cookies.isEmpty()) {
             for (Map.Entry<String, List<String>> header : headers.getHeaders().entrySet()) {

providers/netty/src/main/java/com/ning/http/client/providers/netty/NettyResponse.java

@@ -58,7 +58,7 @@ public String getResponseBodyExcerpt(int maxLength, String charset) throws IOExc
 
     public List<Cookie> getCookies() {
         if (headers == null) {
-            throw new IllegalStateException(HEADERS_NOT_COMPUTED);
+            return Collections.emptyList();
         }
         if (cookies.isEmpty()) {
             for (Map.Entry<String, List<String>> header : headers.getHeaders().entrySet()) {