Refactoring: moved FacebookErrorMessage in its own file/class

[facebook-utils] / src / main / java / de / juplo / facebook / client / GraphApiErrorHandler.java

diff --git a/src/main/java/de/juplo/facebook/client/GraphApiErrorHandler.java b/src/main/java/de/juplo/facebook/client/GraphApiErrorHandler.java
index 2b73e49..6b1ab97 100644 (file)
--- a/src/main/java/de/juplo/facebook/client/GraphApiErrorHandler.java
+++ b/src/main/java/de/juplo/facebook/client/GraphApiErrorHandler.java
@@ -4,6 +4,9 @@ import de.juplo.facebook.exceptions.GraphApiException;
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.nio.charset.Charset;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.client.ClientHttpResponse;
@@ -16,12 +19,12 @@ import org.springframework.web.client.ResponseErrorHandler;
  * Error-Handler for error-messages from the Facebook Graph-API.
  * <p>
  * This error-handler handels responses withe the HTTP-status code
- * {@code 4xx}. It tries to extract and parse the error-message
+ * {@code 400 BAD REQUEST}. It tries to extract and parse the error-message
  * from the HTTP-body. Successfully extracted and parsed messages are mapped
  * to a hierarchy of exceptions, that reflects the hierarchy of the error-
  * codes and -types.
  * <p>
- * If the HTTP-status-code of the response is not {@code 4xx} or
+ * If the HTTP-status-code of the response is not {@code 400 BAD REQUEST} or
  * the HTTP-body could not be extracted or parsed, this error-handler
  * delegates the handling to its parent.
  *
@@ -31,6 +34,9 @@ import org.springframework.web.client.ResponseErrorHandler;
  */
 public class GraphApiErrorHandler implements ResponseErrorHandler
 {
+  private final static Logger LOG =
+      LoggerFactory.getLogger(GraphApiErrorHandler.class);
+
   private final ResponseErrorHandler parent;
 
 
@@ -51,10 +57,10 @@ public class GraphApiErrorHandler implements ResponseErrorHandler
   @Override
   public void handleError(final ClientHttpResponse response) throws IOException
   {
-    if (!HttpStatus.Series.CLIENT_ERROR.equals(response.getStatusCode().series()))
+    if (!HttpStatus.BAD_REQUEST.equals(response.getStatusCode()))
     {
-      // Let the parent-error-handler handle all errors, that are no client
-      // errors (4xx).
+      // We will only handle 400 BAD REQUEST
+      LOG.debug("ignoring response with status-code {}.", response.getStatusCode());
       parent.handleError(response);
       return;
     }
@@ -63,6 +69,7 @@ public class GraphApiErrorHandler implements ResponseErrorHandler
     if (response.getBody() == null)
     {
       // There is no body to interpret in the HTTP-message
+      LOG.warn("Could not convert the response into an exception, because there is no message-body.");
       parent.handleError(response);
       return;
     }
@@ -73,12 +80,16 @@ public class GraphApiErrorHandler implements ResponseErrorHandler
     try
     {
       error = GraphApiException.create(body);
+      if (LOG.isInfoEnabled())
+        LOG.info("error-response: {}", new String(body, Charset.forName("UTF-8")));
     }
     catch (Exception e)
     {
       // The body of the HTTP-message could not be parsed.
       // Let the parent error-handler try to handle the response.
 
+      LOG.warn("Could not convert the response into an exception, because the body is unparsable: {}", body);
+
       // To do so, we have to wrap the original response to fill in
       // the buffered body, if needed
       ClientHttpResponse buffered = new ClientHttpResponse()