[OLINGO-659] more API clean-up

Signed-off-by: Michael Bolz <michael.bolz@sap.com>

lib/commons-api/src/main/java/org/apache/olingo/commons/api/http/HttpHeader.java

@@ -18,271 +18,162 @@
  */
 package org.apache.olingo.commons.api.http;
 
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.List;
-import java.util.Locale;
-
 /**
  * HTTP header constants.
  */
-public class HttpHeader {
+public interface HttpHeader {
 
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.1">HTTP/1.1 documentation</a>}.
    */
-  public static final String ACCEPT = "Accept";
+  String ACCEPT = "Accept";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.2">HTTP/1.1 documentation</a>}.
    */
-  public static final String ACCEPT_CHARSET = "Accept-Charset";
+  String ACCEPT_CHARSET = "Accept-Charset";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.3">HTTP/1.1 documentation</a>}.
    */
-  public static final String ACCEPT_ENCODING = "Accept-Encoding";
+  String ACCEPT_ENCODING = "Accept-Encoding";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.4">HTTP/1.1 documentation</a>}.
    */
-  public static final String ACCEPT_LANGUAGE = "Accept-Language";
+  String ACCEPT_LANGUAGE = "Accept-Language";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.7">HTTP/1.1 documentation</a>}.
    */
-  public static final String ALLOW = "Allow";
+  String ALLOW = "Allow";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.8">HTTP/1.1 documentation</a>}.
    */
-  public static final String AUTHORIZATION = "Authorization";
+  String AUTHORIZATION = "Authorization";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.9">HTTP/1.1 documentation</a>}.
    */
-  public static final String CACHE_CONTROL = "Cache-Control";
+  String CACHE_CONTROL = "Cache-Control";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.11">HTTP/1.1 documentation</a>}.
    */
-  public static final String CONTENT_ENCODING = "Content-Encoding";
+  String CONTENT_ENCODING = "Content-Encoding";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.12">HTTP/1.1 documentation</a>}.
    */
-  public static final String CONTENT_LANGUAGE = "Content-Language";
+  String CONTENT_LANGUAGE = "Content-Language";
   /** See <a href="http://www.rfc-editor.org/rfc/rfc2392.txt">RFC 2392</a>. */
-  public static final String CONTENT_ID = "Content-ID";
+  String CONTENT_ID = "Content-ID";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.13">HTTP/1.1 documentation</a>}.
    */
-  public static final String CONTENT_LENGTH = "Content-Length";
+  String CONTENT_LENGTH = "Content-Length";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.14">HTTP/1.1 documentation</a>}.
    */
-  public static final String CONTENT_LOCATION = "Content-Location";
+  String CONTENT_LOCATION = "Content-Location";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.17">HTTP/1.1 documentation</a>}.
    */
-  public static final String CONTENT_TYPE = "Content-Type";
+  String CONTENT_TYPE = "Content-Type";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.18">HTTP/1.1 documentation</a>}.
    */
-  public static final String DATE = "Date";
+  String DATE = "Date";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.19">HTTP/1.1 documentation</a>}.
    */
-  public static final String ETAG = "ETag";
+  String ETAG = "ETag";
   /** See <a href="http://www.rfc-editor.org/rfc/rfc7231.txt">RFC 7231</a>. */
-  public static final String EXPECT = "Expect";
+  String EXPECT = "Expect";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.21">HTTP/1.1 documentation</a>}.
    */
-  public static final String EXPIRES = "Expires";
+  String EXPIRES = "Expires";
   /** See <a href="http://www.rfc-editor.org/rfc/rfc7231.txt">RFC 7231</a>. */
-  public static final String FROM = "From";
+  String FROM = "From";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.23">HTTP/1.1 documentation</a>}.
    */
-  public static final String HOST = "Host";
+  String HOST = "Host";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.24">HTTP/1.1 documentation</a>}.
    */
-  public static final String IF_MATCH = "If-Match";
+  String IF_MATCH = "If-Match";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.25">HTTP/1.1 documentation</a>}.
    */
-  public static final String IF_MODIFIED_SINCE = "If-Modified-Since";
+  String IF_MODIFIED_SINCE = "If-Modified-Since";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.26">HTTP/1.1 documentation</a>}.
    */
-  public static final String IF_NONE_MATCH = "If-None-Match";
+  String IF_NONE_MATCH = "If-None-Match";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.28">HTTP/1.1 documentation</a>}.
    */
-  public static final String IF_UNMODIFIED_SINCE = "If-Unmodified-Since";
+  String IF_UNMODIFIED_SINCE = "If-Unmodified-Since";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.29">HTTP/1.1 documentation</a>}.
    */
-  public static final String LAST_MODIFIED = "Last-Modified";
+  String LAST_MODIFIED = "Last-Modified";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.30">HTTP/1.1 documentation</a>}.
    */
-  public static final String LOCATION = "Location";
+  String LOCATION = "Location";
   /**
    * See {@link <a href="http://tools.ietf.org/html/rfc5988#page-6">Web Linking (IETF RFC-5988) documentation</a>}.
    */
-  public static final String LINK = "Link";
+  String LINK = "Link";
   /** See <a href="http://www.rfc-editor.org/rfc/rfc7231.txt">RFC 7231</a>. */
-  public static final String MAX_FORWARDS = "Max-Forwards";
+  String MAX_FORWARDS = "Max-Forwards";
   /**
    * OData Prefer Header.
    * See <a href="http://docs.oasis-open.org/odata/odata/v4.0/odata-v4.0-part1-protocol.html#_Toc406398233">
    * OData Version 4.0 Part 1: Protocol</a> and <a href="https://www.ietf.org/rfc/rfc7240.txt">RFC 7240</a>.
    */
-  public static final String PREFER = "Prefer";
+  String PREFER = "Prefer";
   /**
    * OData Preference-Applied Header.
    * See <a href="http://docs.oasis-open.org/odata/odata/v4.0/odata-v4.0-part1-protocol.html#_Toc406398247">
    * OData Version 4.0 Part 1: Protocol</a> and <a href="https://www.ietf.org/rfc/rfc7240.txt">RFC 7240</a>.
    */
-  public static final String PREFERENCE_APPLIED = "Preference-Applied";
+  String PREFERENCE_APPLIED = "Preference-Applied";
   /** See <a href="http://www.rfc-editor.org/rfc/rfc7233.txt">RFC 7233</a>. */
-  public static final String RANGE = "Range";
+  String RANGE = "Range";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.37">HTTP/1.1 documentation</a>}.
    */
-  public static final String RETRY_AFTER = "Retry-After";
+  String RETRY_AFTER = "Retry-After";
   /** See <a href="http://www.rfc-editor.org/rfc/rfc7230.txt">RFC 7230</a>. */
-  public static final String TE = "TE";
+  String TE = "TE";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.43">HTTP/1.1 documentation</a>}.
    */
-  public static final String USER_AGENT = "User-Agent";
+  String USER_AGENT = "User-Agent";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.44">HTTP/1.1 documentation</a>}.
    */
-  public static final String VARY = "Vary";
+  String VARY = "Vary";
   /**
    * See {@link <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.47">HTTP/1.1 documentation</a>}.
    */
-  public static final String WWW_AUTHENTICATE = "WWW-Authenticate";
+  String WWW_AUTHENTICATE = "WWW-Authenticate";
 
   /**
    * See {@link <a href="http://www.ietf.org/rfc/rfc2109.txt">IETF RFC 2109</a>}.
    */
-  public static final String COOKIE = "Cookie";
+  String COOKIE = "Cookie";
   /**
    * See {@link <a href="http://www.ietf.org/rfc/rfc2109.txt">IETF RFC 2109</a>}.
    */
-  public static final String SET_COOKIE = "Set-Cookie";
+  String SET_COOKIE = "Set-Cookie";
 
   /** Non standard header. */
-  public static final String X_HTTP_METHOD = "X-HTTP-Method";
+  String X_HTTP_METHOD = "X-HTTP-Method";
   /** Non standard header. */
-  public static final String X_HTTP_METHOD_OVERRIDE = "X-HTTP-Method-Override";
+  String X_HTTP_METHOD_OVERRIDE = "X-HTTP-Method-Override";
 
   /** Custom Header defined in the OData standard. */
-  public static final String ODATA_VERSION = "OData-Version";
+  String ODATA_VERSION = "OData-Version";
   /** Custom Header defined in the OData standard. */
-  public static final String ODATA_MAX_VERSION = "OData-MaxVersion";
+  String ODATA_MAX_VERSION = "OData-MaxVersion";
   /** Custom Header defined in the OData standard. */
-  public static final String ODATA_ENTITY_ID = "OData-EntityID";
+  String ODATA_ENTITY_ID = "OData-EntityID";
-
-  private final String name;
-  private final List<String> values;
-
-  /**
-   * Create header for given name
-   * @param name of header
-   */
-  public HttpHeader(String name) {
-    this.name = name;
-    this.values = new ArrayList<String>();
-  }
-
-  /**
-   * Create header for given name and add given values
-   * @param name of header
-   * @param values values for header
-   */
-  public HttpHeader(String name, Collection<String> values) {
-    this(name);
-    this.values.addAll(values);
-  }
-
-  /**
-   * Get name of header (not the canonical name)
-   * @return name of header
-   */
-  public String getName() {
-    return name;
-  }
-
-  /**
-   * Get all values for this header
-   * @return all header values
-   */
-  public List<String> getValues() {
-    return Collections.unmodifiableList(values);
-  }
-
-  /**
-   * Add header value
-   *
-   * @param value value to be added
-   * @return this header object (fluent interface)
-   */
-  public HttpHeader addValue(String value) {
-    this.values.add(value);
-    return this;
-  }
-
-  /**
-   * Add header values
-   *
-   * @param values values to be added
-   * @return this header object (fluent interface)
-   */
-  public HttpHeader addValues(Collection<String> values) {
-    this.values.addAll(values);
-    return this;
-  }
-
-  /**
-   * Get the canonical name of header
-   * @return canonical name of header
-   */
-  public String getCanonicalName() {
-    return createCanonicalName(name);
-  }
-
-  /**
-   * Create the canonical name based on given name parameter
-   *
-   * @param name name which is canonicalised
-   * @return canonical name
-   */
-  public static String createCanonicalName(String name) {
-    return name.toLowerCase(Locale.ROOT);
-  }
-
-  @Override
-  public boolean equals(Object o) {
-    if (this == o) {
-      return true;
-    }
-    if (o == null || getClass() != o.getClass()) {
-      return false;
-    }
-
-    HttpHeader that = (HttpHeader) o;
-
-    if (!name.equals(that.name)) {
-      return false;
-    }
-    return values.equals(that.values);
-
-  }
-
-  @Override
-  public int hashCode() {
-    int result = name.hashCode();
-    result = 31 * result + values.hashCode();
-    return result;
-  }
 }

lib/server-api/src/main/java/org/apache/olingo/server/api/HttpHeaders.java

@@ -22,132 +22,111 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.LinkedHashMap;
-import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
-import org.apache.olingo.commons.api.http.HttpHeader;
-
 /**
- * HttpHeader container
+ * HttpHeader container.
  */
 public class HttpHeaders {
-  private final Map<String, HttpHeader> headers = new LinkedHashMap<String, HttpHeader>();
+  private final Map<String, List<String>> headers = new LinkedHashMap<String, List<String>>();
 
   /**
-   * Add a header with given name and value.
+   * Adds a header with given name and value.
-   * If header with name already exists the value is added to this header.
+   * If a header with that name already exists the value is added to this header.
-   *
    * @param name name of header
    * @param value value for header
    * @return this container (fluent interface)
    */
-  public HttpHeaders addHeader(String name, String value) {
+  public HttpHeaders addHeader(final String name, final String value) {
-    HttpHeader eh = grantHeader(name);
+    final String canonicalName = getCanonicalName(name);
-    eh.addValue(value);
+    List<String> header = headers.get(canonicalName);
+    if (header == null) {
+      header = new ArrayList<String>();
+    }
+    header.add(value);
+    headers.put(canonicalName, header);
     return this;
   }
 
   /**
-   * Add a header with given name and values.
+   * Adds a header with the given name and values.
-   * If header with name already exists the values are added to this header.
+   * If a header with that name already exists the values are added to this header.
-   *
    * @param name name of header
    * @param values values for header
    * @return this container (fluent interface)
    */
-  public HttpHeaders addHeader(String name, Collection<String> values) {
+  public HttpHeaders addHeader(final String name, final List<String> values) {
-    HttpHeader eh = grantHeader(name);
+    final String canonicalName = getCanonicalName(name);
-    eh.addValues(values);
+    List<String> header = headers.get(canonicalName);
+    if (header == null) {
+      header = new ArrayList<String>();
+    }
+    header.addAll(values);
+    headers.put(canonicalName, header);
     return this;
   }
 
   /**
    * Set a header with given name and value.
-   * If header with name already exists the old header is replaced with the new one.
+   * If a header with that name already exists the old header is replaced with the new one.
-   *
    * @param name name of header
    * @param value value for header
    * @return this container (fluent interface)
    */
-  public HttpHeaders setHeader(String name, String value) {
+  public HttpHeaders setHeader(final String name, final String value) {
     removeHeader(name);
-
+    addHeader(name, value);
-    HttpHeader eh = grantHeader(name);
-    eh.addValue(value);
     return this;
   }
 
   /**
-   * Get header for given name.
+   * Gets header values for the given name.
-   *
    * @param name name of header requested
-   * @return corresponding header
+   * @return corresponding header values or null if no values have been found
    */
-  public HttpHeader getHeader(String name) {
+  public List<String> getHeader(final String name) {
-    return headers.get(HttpHeader.createCanonicalName(name));
+    final List<String> values = headers.get(getCanonicalName(name));
+    return values == null || values.isEmpty() ? null : Collections.unmodifiableList(values);
   }
 
   /**
-   * Remove header for given name.
+   * Removes header of the given name.
-   *
    * @param name name of header to be removed
-   * @return header which was removed or null if no header was known for this name
+   * @return removed header values or null if no header was known for this name
    */
-  public HttpHeader removeHeader(String name) {
+  public List<String> removeHeader(final String name) {
-    return headers.remove(HttpHeader.createCanonicalName(name));
+    return headers.remove(getCanonicalName(name));
   }
 
-
   /**
-   * Get all headers.
+   * Gets all headers with the according values.
-   *
+   * @return an unmodifiable Map of header names/values or an empty collection if no headers have been set
-   * @return all headers
-   */
-  public Collection<HttpHeader> getHeaders() {
-    return Collections.unmodifiableCollection(headers.values());
-  }
-
-
-  /**
-   * Get all headers with the according values.
-   *
-   * @return an unmodifiable Map of header names/values
    */
   public Map<String, List<String>> getHeaderToValues() {
-    Map<String, List<String>> result = new HashMap<String, List<String>>();
+    return headers.isEmpty() ? Collections.<String, List<String>> emptyMap() : Collections.unmodifiableMap(headers);
-    Collection<HttpHeader> allHeaders = headers.values();
-    for (HttpHeader header : allHeaders) {
-      result.put(header.getName(), header.getValues());
-    }
-    return Collections.unmodifiableMap(result);
   }
 
   /**
-   * Get all header names.
+   * Gets all header names.
-   *
+   * @return all header names or an empty collection if no headers have been set
-   * @return all header names
    */
   public Collection<String> getHeaderNames() {
-    Collection<String> headerNames = new ArrayList<String>();
+    return headers.isEmpty() ? Collections.<String> emptySet() : Collections.unmodifiableSet(headers.keySet());
-    for (HttpHeader header : headers.values()) {
-      headerNames.add(header.getName());
-    }
-    return headerNames;
   }
 
   /**
-   * Get or create a header for given name.
+   * The canonical form of a header name is the already-used form regarding case,
-   *
+   * enabling applications to have pretty-looking headers instead of getting them
-   * @return new or known header
+   * converted to all lowercase.
+   * @param name HTTP header name
    */
-  private HttpHeader grantHeader(String name) {
+  private String getCanonicalName(final String name) {
-    String key = HttpHeader.createCanonicalName(name);
+    for (final String headerName : headers.keySet()) {
-    HttpHeader eh = headers.get(key);
+      if (headerName.equalsIgnoreCase(name)) {
-    if(eh == null) {
+        return headerName;
-      eh = new HttpHeader(name);
+      }
-      headers.put(key, eh);
     }
-    return eh;
+    return name;
   }
 }

lib/server-api/src/main/java/org/apache/olingo/server/api/OData.java

@@ -125,7 +125,7 @@ public abstract class OData {
 
   /**
    * Creates a new deserializer object for reading content in the specified format.
-   * Deserializer are used in Processor implementations.
+   * Deserializers are used in Processor implementations.
    *
    * @param contentType any content type supported by Olingo (XML, JSON ...)
    */
@@ -151,10 +151,11 @@ public abstract class OData {
   public abstract Preferences createPreferences(Collection<String> preferHeaders);
 
   /**
-   * This method creates a DebugResponseHelper for the given debugFormat. If the format is not supported no
+   * Creates a DebugResponseHelper for the given debugFormat.
-   * exception is thrown. Instead we give back the implementation for the json format.
+   * If the format is not supported no exception is thrown.
-   * @param debugFormat to be used.
+   * Instead we give back the implementation for the JSON format.
-   * @return a debug response serializer
+   * @param debugFormat format to be used
+   * @return a debug-response helper
    */
   public abstract DebugResponseHelper createDebugResponseHelper(String debugFormat);
 }

lib/server-api/src/main/java/org/apache/olingo/server/api/ODataHttpHandler.java

@@ -62,13 +62,13 @@ public interface ODataHttpHandler {
   void setSplit(int split);
 
   /**
-   * Register this interface to support concurrency control for certain entity sets.
+   * Registers support for concurrency control for certain entity sets.
    * @param customETagSupport
    */
   void register(CustomETagSupport customConcurrencyControlSupport);
 
   /**
-   * Register the debug support handler
+   * Registers the debug support handler.
    * @param debugSupport
    */
   void register(DebugSupport debugSupport);

lib/server-api/src/main/java/org/apache/olingo/server/api/ODataRequest.java

@@ -19,11 +19,9 @@
 package org.apache.olingo.server.api;
 
 import java.io.InputStream;
-import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 
-import org.apache.olingo.commons.api.http.HttpHeader;
 import org.apache.olingo.commons.api.http.HttpMethod;
 
 /**
@@ -93,26 +91,22 @@ public class ODataRequest {
   }
 
   /**
-   * Get header values for a given name.
+   * Gets header values for a given name.
    * @param name the header name as a case-insensitive key
    * @return the header value(s) or null if not found
    */
   public List<String> getHeaders(final String name) {
-    HttpHeader h = headers.getHeader(name);
+    return headers.getHeader(name);
-    if(h == null) {
-      return null;
-    }
-    return new ArrayList<String>(h.getValues());
   }
 
   /**
-   * Get first header value for a given name.
+   * Gets first header value for a given name.
    * @param name the header name as a case-insensitive key
    * @return the first header value or null if not found
    */
   public String getHeader(final String name) {
     final List<String> values = getHeaders(name);
-    return values == null ? null : values.get(0);
+    return values == null || values.isEmpty() ? null : values.get(0);
   }
 
   /**
@@ -123,7 +117,6 @@ public class ODataRequest {
     return headers.getHeaderToValues();
   }
 
-
   /**
    * Gets the body of the request.
    * @return the request payload as {@link InputStream} or null

lib/server-api/src/main/java/org/apache/olingo/server/api/ODataResponse.java

@@ -19,11 +19,9 @@
 package org.apache.olingo.server.api;
 
 import java.io.InputStream;
-import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 
-import org.apache.olingo.commons.api.http.HttpHeader;
 import org.apache.olingo.commons.api.http.HttpStatusCode;
 
 /**
@@ -102,11 +100,7 @@ public class ODataResponse {
    * @return the header value(s) or null if not found
    */
   public List<String> getHeaders(final String name) {
-    HttpHeader h = headers.getHeader(name);
+    return headers.getHeader(name);
-    if(h == null) {
-      return null;
-    }
-    return new ArrayList<String>(h.getValues());
   }
 
   /**
@@ -118,7 +112,7 @@ public class ODataResponse {
    */
   public String getHeader(final String name) {
     final List<String> values = getHeaders(name);
-    return values == null ? null : values.get(0);
+    return values == null || values.isEmpty() ? null : values.get(0);
   }
 
 

lib/server-api/src/main/java/org/apache/olingo/server/api/batch/BatchFacade.java

@@ -25,50 +25,49 @@ import org.apache.olingo.server.api.deserializer.batch.BatchRequestPart;
 import org.apache.olingo.server.api.deserializer.batch.ODataResponsePart;
 
 /**
- * Provides methods to process {@link ODataRequest} and {@link BatchRequestPart}.
+ * <p>Provides methods to process {@link ODataRequest}s and {@link BatchRequestPart}s
+ * in the context of a batch request.</p>
  *
- * Within a {@link org.apache.olingo.server.api.processor.BatchProcessor} implementation BatchRequestsParts
+ * <p>Within a {@link org.apache.olingo.server.api.processor.BatchProcessor BatchProcessor}
- * should be passed to {@link BatchFacade#handleBatchRequest(BatchRequestPart)}.
+ * implementation BatchRequestParts should be passed to {@link #handleBatchRequest(BatchRequestPart)}.
- * If only if the BatchRequests part represents a change set, the request will be delegated to
+ * Only if the BatchRequestPart represents a change set, the request will be delegated to
  * {@link org.apache.olingo.server.api.processor.BatchProcessor#processChangeSet(BatchFacade, java.util.List)}.
- * Otherwise the requests will be directly executed.
+ * Otherwise the requests will be directly executed.</p>
  *
- * The processor implementation could use {@link BatchFacade#handleODataRequest(ODataRequest)} to processes
+ * <p>The processor implementation could use {@link #handleODataRequest(ODataRequest)} to process
- * requests in a change set.
+ * requests in a change set.</p>
  */
 public interface BatchFacade {
   /**
-   * Executes a ODataRequest, which must be a part of a change set.
+   * Executes an ODataRequest, which must be a part of a change set.
-   * Each requests must have a Content-Id header field, which holds an id that is unique in the whole batch request.
+   * Each request must have a Content-Id header field, which holds an identifier
-   *
+   * that is unique in the whole batch request.
    * @param request ODataRequest to process
-   * @return Corresponding ODataResult to the given request
+   * @return corresponding ODataResponse to the given request
    * @throws ODataApplicationException
    * @throws ODataLibraryException
    */
-  public ODataResponse handleODataRequest(ODataRequest request) throws ODataApplicationException,
+  public ODataResponse handleODataRequest(ODataRequest request)
-      ODataLibraryException;
+      throws ODataApplicationException, ODataLibraryException;
 
   /**
    * Handles a BatchRequestPart.
-   *
    * @param request Request to process
-   * @return Corresponding {@link ODataResponsePart}
+   * @return corresponding {@link ODataResponsePart}
    * @throws ODataApplicationException
    * @throws ODataLibraryException
    */
-  public ODataResponsePart handleBatchRequest(BatchRequestPart request) throws ODataApplicationException,
+  public ODataResponsePart handleBatchRequest(BatchRequestPart request)
-      ODataLibraryException;
+      throws ODataApplicationException, ODataLibraryException;
 
   /**
    * Extracts the boundary of a multipart/mixed header.
    * See RFC 2046#5.1
-   *
    * @param contentType Content Type
-   * @return Boundary
+   * @return boundary
    * @throws ODataApplicationException
    * @throws ODataLibraryException
    */
-  public String extractBoundaryFromContentType(String contentType) throws ODataApplicationException,
+  public String extractBoundaryFromContentType(String contentType)
-      ODataLibraryException;
+      throws ODataApplicationException, ODataLibraryException;
 }

lib/server-api/src/main/java/org/apache/olingo/server/api/debug/DebugResponseHelper.java

@@ -21,18 +21,14 @@ package org.apache.olingo.server.api.debug;
 import org.apache.olingo.server.api.ODataResponse;
 
 /**
- * This class supports applications in creating debug responses.
+ * Support for applications creating debug responses.
  */
 public interface DebugResponseHelper {
 
   /**
    * Creates a debug response based on the given parameters. Will never throw an exception.
-   * @param request
+   * @param debugInfo debug information
-   * @param applicationResponse
+   * @return the debug response or the raw application response in case an exception occurred
-   * @param exception
-   * @param serverEnvironmentVaribles
-   * @param runtimeInformation
-   * @return the debug response or the raw application response in case an exception occurred.
    */
   ODataResponse createDebugResponse(DebugInformation debugInfo);
 }

lib/server-api/src/main/java/org/apache/olingo/server/api/deserializer/ODataDeserializer.java

@@ -30,10 +30,10 @@ import org.apache.olingo.commons.api.edm.EdmProperty;
 public interface ODataDeserializer {
 
   /**
-   * Deserializes an entity stream into an {@link org.apache.olingo.commons.api.data.Entity} object.
+   * Deserializes an entity stream into an {@link org.apache.olingo.commons.api.data.Entity Entity} object.
-   * Validates: property types, no double properties, correct json types
+   * Validates: property types, no double properties, correct json types.
-   * Returns a deserialized {@link org.apache.olingo.commons.api.data.Entity} object and an 
+   * Returns a deserialized {@link org.apache.olingo.commons.api.data.Entity Entity} object and an 
-   * {@link org.apache.olingo.server.api.uri.queryoption.ExpandOption} object
+   * {@link org.apache.olingo.server.api.uri.queryoption.ExpandOption ExpandOption} object.
    * @param stream
    * @param edmEntityType
    * @return {@link DeserializerResult#getEntity()} and {@link DeserializerResult#getExpandTree()}
@@ -42,7 +42,8 @@ public interface ODataDeserializer {
   DeserializerResult entity(InputStream stream, EdmEntityType edmEntityType) throws DeserializerException;
 
   /**
-   * Deserializes an entity collection stream into an {@link org.apache.olingo.commons.api.data.EntityCollection} object
+   * Deserializes an entity collection stream into an
+   * {@link org.apache.olingo.commons.api.data.EntityCollection EntityCollection} object.
    * @param stream
    * @param edmEntityType
    * @return {@link DeserializerResult#getEntityCollection()}
@@ -51,7 +52,7 @@ public interface ODataDeserializer {
   DeserializerResult entityCollection(InputStream stream, EdmEntityType edmEntityType) throws DeserializerException;
 
   /**
-   * Deserializes an action-parameters stream into an {@link org.apache.olingo.commons.api.data.Entity} object.
+   * Deserializes an action-parameters stream into a map of key/value pairs.
    * Validates: parameter types, no double parameters, correct json types.
    * @param stream
    * @param edmAction
@@ -61,7 +62,7 @@ public interface ODataDeserializer {
   DeserializerResult actionParameters(InputStream stream, EdmAction edmAction) throws DeserializerException;
 
   /**
-   * Deserializes the Property or collections of properties (primitive & complex)
+   * Deserializes the Property or collections of properties (primitive & complex).
    * @param stream
    * @param edmProperty
    * @return {@link DeserializerResult#getProperty()}
@@ -70,7 +71,7 @@ public interface ODataDeserializer {
   DeserializerResult property(InputStream stream, EdmProperty edmProperty) throws DeserializerException;
 
   /**
-   * Read entity references from the provided document
+   * Reads entity references from the provided document.
    * @param stream
    * @param keys
    * @return {@link DeserializerResult#getEntityReferences()}

lib/server-api/src/main/java/org/apache/olingo/server/api/deserializer/batch/BatchDeserializerException.java

@@ -22,26 +22,49 @@ import org.apache.olingo.server.api.deserializer.DeserializerException;
 
 public class BatchDeserializerException extends DeserializerException {
   public static enum MessageKeys implements MessageKey {
+    /** parameter: line */
     INVALID_BOUNDARY,
+    /** parameter: line */
     INVALID_CHANGESET_METHOD,
+    /** parameter: line */
     INVALID_CONTENT,
+    /** parameter: line */
     INVALID_CONTENT_LENGTH,
+    /** parameter: line */
     INVALID_CONTENT_TRANSFER_ENCODING,
+    /** parameter: line */
     INVALID_CONTENT_TYPE,
-    INVALID_HEADER,
+    /** parameters: line, expected content type, actual content type */
+    UNEXPECTED_CONTENT_TYPE,
+    /** parameter: line */
+    INVALID_CONTENT_ID,
+    /** parameter: line */
     INVALID_HTTP_VERSION,
+    /** parameter: line */
     INVALID_METHOD,
+    /** parameter: line */
     INVALID_QUERY_OPERATION_METHOD,
+    /** parameter: line */
     INVALID_STATUS_LINE,
+    /** parameter: line */
     INVALID_URI,
+    /** parameter: line */
     MISSING_BLANK_LINE,
+    /** parameter: line */
     MISSING_BOUNDARY_DELIMITER,
+    /** parameter: line */
     MISSING_CLOSE_DELIMITER,
+    /** parameter: line */
     MISSING_CONTENT_ID,
+    /** parameter: line */
     MISSING_CONTENT_TRANSFER_ENCODING,
+    /** parameter: line */
     MISSING_CONTENT_TYPE,
+    /** parameter: line */
     MISSING_MANDATORY_HEADER,
+    /** parameter: line */
     FORBIDDEN_HEADER,
+    /** parameter: line */
     INVALID_BASE_URI;
 
     @Override

lib/server-api/src/main/java/org/apache/olingo/server/api/deserializer/batch/BatchOptions.java

@@ -20,9 +20,8 @@ package org.apache.olingo.server.api.deserializer.batch;
 
 /**
  * Options for the batch deserializer.
- * See
+ * @see org.apache.olingo.server.api.deserializer.FixedFormatDeserializer
- * {@link org.apache.olingo.server.api.deserializer.FixedFormatDeserializer
+ * #parseBatchRequest(java.io.InputStream, String, BatchOptions)
- *  #parseBatchRequest(java.io.InputStream, String, BatchOptions)}
  */
 public final class BatchOptions {
   private boolean isStrict = true;
@@ -33,8 +32,7 @@ public final class BatchOptions {
 
   /**
    * Returns if the batch parsing is strict.
-   * Default is true
+   * Default is true.
-   *
    * @return true if parsing is strict
    */
   public boolean isStrict() {
@@ -42,22 +40,23 @@ public final class BatchOptions {
   }
 
   /**
-   * See {@link org.apache.olingo.server.api.ODataRequest#getRawBaseUri()}
+   * Gets raw base URI.
+   * @see org.apache.olingo.server.api.ODataRequest#getRawBaseUri()
    */
   public String getRawBaseUri() {
     return rawBaseUri;
   }
 
   /**
-   * See {@link org.apache.olingo.server.api.ODataRequest#getRawServiceResolutionUri()}
+   * Gets raw service resolution URI.
+   * @see org.apache.olingo.server.api.ODataRequest#getRawServiceResolutionUri()
    */
   public String getRawServiceResolutionUri() {
     return rawServiceResolutionUri;
   }
 
   /**
-   * Creates a new BatchOptions builder
+   * Creates a new BatchOptions builder.
-   *
    * @return new BatchOptions builder instance
    */
   public static Builder with() {
@@ -76,7 +75,7 @@ public final class BatchOptions {
     }
 
     /**
-     * See {@link BatchOptions#isStrict()}
+     * @see BatchOptions#isStrict()
      */
     public Builder isStrict(final boolean isStrict) {
       options.isStrict = isStrict;
@@ -84,7 +83,7 @@ public final class BatchOptions {
     }
 
     /**
-     * See {@link org.apache.olingo.server.api.ODataRequest#getRawBaseUri()}
+     * @see org.apache.olingo.server.api.ODataRequest#getRawBaseUri()
      */
     public Builder rawBaseUri(final String baseUri) {
       options.rawBaseUri = baseUri;
@@ -92,7 +91,7 @@ public final class BatchOptions {
     }
 
     /**
-     * See {@link org.apache.olingo.server.api.ODataRequest#getRawServiceResolutionUri()}
+     * @see org.apache.olingo.server.api.ODataRequest#getRawServiceResolutionUri()
      */
     public Builder rawServiceResolutionUri(final String serviceResolutionUri) {
       options.rawServiceResolutionUri = serviceResolutionUri;
@@ -100,8 +99,7 @@ public final class BatchOptions {
     }
 
     /**
-     * Creates a new BatchOptions instance
+     * Creates a new BatchOptions instance.
-     *
      * @return new BatchOptions instance
      */
     public BatchOptions build() {

lib/server-api/src/main/java/org/apache/olingo/server/api/deserializer/batch/BatchRequestPart.java

@@ -25,16 +25,14 @@ import java.util.List;
 import org.apache.olingo.server.api.ODataRequest;
 
 /**
- * A BatchPart
+ * Represents a distinct MIME part of a Batch Request body - either a Change Set or a Query Operation
- * <p> BatchPart represents a distinct MIME part of a Batch Request body. It can be a ChangeSet or a Query Operation
  */
 public class BatchRequestPart {
   private List<ODataRequest> requests = new ArrayList<ODataRequest>();
   private boolean isChangeSet;
 
   /**
-   * Creates a new instance of BachRequestPart
+   * Creates a new instance of BachRequestPart.
-   *
    * @param isChangeSet True, if this instance represents a change set
    * @param requests A list of {@link ODataRequest}
    */
@@ -44,8 +42,7 @@ public class BatchRequestPart {
   }
 
   /**
-   * Creates a new instance of BachRequestPart
+   * Creates a new instance of BachRequestPart.
-   *
    * @param isChangeSet True, if this instance represents a change set
    * @param request A single {@link ODataRequest}
    */
@@ -56,7 +53,7 @@ public class BatchRequestPart {
   }
 
   /**
-   * Get the info if a BatchPart is a ChangeSet
+   * Gets the info if a BatchPart is a ChangeSet.
    * @return true or false
    */
   public boolean isChangeSet() {
@@ -64,7 +61,7 @@ public class BatchRequestPart {
   }
 
   /**
-   * Get requests. If a BatchPart is a Query Operation, the list contains one request.
+   * Gets all requests of this part. If a BatchPart is a Query Operation, the list contains one request.
    * @return a list of {@link ODataRequest}
    */
   public List<ODataRequest> getRequests() {

lib/server-api/src/main/java/org/apache/olingo/server/api/serializer/ReferenceCollectionSerializerOptions.java

@@ -21,7 +21,7 @@ package org.apache.olingo.server.api.serializer;
 import org.apache.olingo.commons.api.data.ContextURL;
 import org.apache.olingo.server.api.uri.queryoption.CountOption;
 
-/** Options for the OData serializer. */
+/** Options to pass as additional information to the reference-collection serializer. */
 public final class ReferenceCollectionSerializerOptions {
   private ContextURL contextURL;
   private CountOption count;

lib/server-api/src/main/java/org/apache/olingo/server/api/serializer/ReferenceSerializerOptions.java

@@ -21,7 +21,7 @@ package org.apache.olingo.server.api.serializer;
 import org.apache.olingo.commons.api.data.ContextURL;
 
 /**
- * Use this options calls to pass additional information to the reference serializer.
+ * Options to pass as additional information to the reference serializer.
  */
 public final class ReferenceSerializerOptions {
   private ContextURL contextURL;

lib/server-core/src/main/java/org/apache/olingo/server/core/deserializer/batch/BatchParserCommon.java

@@ -93,7 +93,8 @@ public class BatchParserCommon {
       return type;
     } else {
       throw new BatchDeserializerException("Content type is not the expected content type",
-          BatchDeserializerException.MessageKeys.INVALID_CONTENT_TYPE, expected.toContentTypeString());
+          BatchDeserializerException.MessageKeys.UNEXPECTED_CONTENT_TYPE,
+          Integer.toString(line), expected.toContentTypeString(), type.toContentTypeString());
     }
   }
 

lib/server-core/src/main/java/org/apache/olingo/server/core/deserializer/batch/BatchRequestTransformator.java

@@ -84,14 +84,14 @@ public class BatchRequestTransformator {
   }
 
   private HeaderField getContentId(final BatchQueryOperation queryOperation) throws BatchDeserializerException {
-    final HeaderField contentTypeHeader = queryOperation.getHeaders().getHeaderField(HttpHeader.CONTENT_ID);
+    final HeaderField contentIdHeader = queryOperation.getHeaders().getHeaderField(HttpHeader.CONTENT_ID);
 
-    if (contentTypeHeader != null) {
+    if (contentIdHeader != null) {
-      if (contentTypeHeader.getValues().size() == 1) {
+      if (contentIdHeader.getValues().size() == 1) {
-        return contentTypeHeader;
+        return contentIdHeader;
       } else {
-        throw new BatchDeserializerException("Invalid header", MessageKeys.INVALID_HEADER,
+        throw new BatchDeserializerException("Invalid Content-ID header", MessageKeys.INVALID_CONTENT_ID,
-            Integer.toString(contentTypeHeader.getLineNumber()));
+            Integer.toString(contentIdHeader.getLineNumber()));
       }
     }
 

lib/server-core/src/main/java/org/apache/olingo/server/core/deserializer/batch/BatchTransformatorCommon.java

@@ -56,7 +56,8 @@ public class BatchTransformatorCommon {
               Integer.toString(headers.getLineNumber()));
         }
       } else {
-        throw new BatchDeserializerException("Invalid header", MessageKeys.INVALID_HEADER,
+        throw new BatchDeserializerException("Invalid Content-Transfer-Encoding header",
+            MessageKeys.INVALID_CONTENT_TRANSFER_ENCODING,
             Integer.toString(headers.getLineNumber()));
       }
     } else {
@@ -82,7 +83,7 @@ public class BatchTransformatorCommon {
 
         return contentLength;
       } catch (NumberFormatException e) {
-        throw new BatchDeserializerException("Invalid header", e, MessageKeys.INVALID_HEADER,
+        throw new BatchDeserializerException("Invalid content length", e, MessageKeys.INVALID_CONTENT_LENGTH,
             Integer.toString(contentLengthField.getLineNumber()));
       }
     }

lib/server-core/src/main/java/org/apache/olingo/server/core/serializer/BatchResponseSerializer.java

@@ -138,13 +138,13 @@ public class BatchResponseSerializer {
     final Map<String, List<String>> header = response.getAllHeaders();
 
     for (final Map.Entry<String, List<String>> entry : header.entrySet()) {
-      // Requests do never has a content id header
+      // Requests never have a content id header.
       if (!entry.getKey().equalsIgnoreCase(HttpHeader.CONTENT_ID)) {
         appendHeader(entry.getKey(), entry.getValue().get(0), builder);
       }
     }
 
-    appendHeader(HttpHeader.CONTENT_LENGTH, "" + contentLength, builder);
+    appendHeader(HttpHeader.CONTENT_LENGTH, Integer.toString(contentLength), builder);
   }
 
   private void appendBodyPartHeader(final ODataResponse response, final BodyBuilder builder,
@@ -153,7 +153,7 @@ public class BatchResponseSerializer {
     appendHeader(BatchParserCommon.CONTENT_TRANSFER_ENCODING, BatchParserCommon.BINARY_ENCODING, builder);
 
     if (isChangeSet) {
-      if (response.getAllHeaders().get(HttpHeader.CONTENT_ID) != null) {
+      if (response.getHeader(HttpHeader.CONTENT_ID) != null) {
         appendHeader(HttpHeader.CONTENT_ID, response.getHeader(HttpHeader.CONTENT_ID), builder);
       } else {
         throw new BatchSerializerException("Missing content id", MessageKeys.MISSING_CONTENT_ID);

lib/server-core/src/main/resources/server-core-exceptions-i18n.properties

@@ -126,14 +126,15 @@ DeserializerException.INVALID_NULL_PARAMETER=The parameter '%1$s' must not be nu
 
 BatchDeserializerException.INVALID_BOUNDARY=Invalid boundary at line '%1$s'.
 BatchDeserializerException.INVALID_CHANGESET_METHOD=Invalid method: a ChangeSet cannot contain retrieve requests at line '%1$s'.
-BatchDeserializerException.INVALID_CONTENT=Retrieve requests must not contain any body content '%1$s'.
+BatchDeserializerException.INVALID_CONTENT=The retrieve request at line '%1$s' must not contain any body content.
-BatchDeserializerException.INVALID_CONTENT_LENGTH=Invalid content length: content length have to be an integer and positive at line '%1$s'.
+BatchDeserializerException.INVALID_CONTENT_LENGTH=The value of the Content-Length HTTP header at line '%1$s' must be a positive integer.
-BatchDeserializerException.INVALID_CONTENT_TRANSFER_ENCODING=The Content-Transfer-Encoding should be binary: line '%1$s'.
+BatchDeserializerException.INVALID_CONTENT_TRANSFER_ENCODING=The Content-Transfer-Encoding at line '%1$s' must be binary.
-BatchDeserializerException.INVALID_CONTENT_TYPE=Content-Type should be '%1$s'.
+BatchDeserializerException.INVALID_CONTENT_TYPE=Invalid Content-Type HTTP header at line '%1$s'.
-BatchDeserializerException.INVALID_HEADER=Invalid header: '%1$s' at line '%2$s'.
+BatchDeserializerException.UNEXPECTED_CONTENT_TYPE=Content-Type at line '%1$s' should be '%2$s' but is '%3$s'.
-BatchDeserializerException.INVALID_HTTP_VERSION=Invalid HTTP version: The version have to be HTTP/1.1 at line '%1$s'.
+BatchDeserializerException.INVALID_CONTENT_ID=Invalid Content-ID HTTP header at line '%1$s'.
+BatchDeserializerException.INVALID_HTTP_VERSION=The HTTP version must be HTTP/1.1 at line '%1$s'.
 BatchDeserializerException.INVALID_METHOD=Invalid HTTP method at line '%1$s'.
-BatchDeserializerException.INVALID_QUERY_OPERATION_METHOD=Invalid method: a query operation can only contain retrieve requests at line '%1$s'.
+BatchDeserializerException.INVALID_QUERY_OPERATION_METHOD=The query operation at line '%1$s' can only contain retrieve requests.
 BatchDeserializerException.INVALID_STATUS_LINE=Invalid HTTP status line at line '%1$s'.
 BatchDeserializerException.INVALID_URI=Invalid URI at line '%1$s'.
 BatchDeserializerException.FORBIDDEN_HEADER=Forbidden header at line '%1$s'.
@@ -144,9 +145,9 @@ BatchDeserializerException.MISSING_CONTENT_ID=Missing content-id at line '%1$s'.
 BatchDeserializerException.MISSING_CONTENT_TRANSFER_ENCODING=Missing content transfer encoding at line '%1$s'.
 BatchDeserializerException.MISSING_CONTENT_TYPE=Missing content-type at line '%1$s'.
 BatchDeserializerException.MISSING_MANDATORY_HEADER=Missing mandatory header at line '%1$s'.
-BatchDeserializerException.INVALID_BASE_URI=The base URI do not match the service base URI  at line '%1$s'.
+BatchDeserializerException.INVALID_BASE_URI=The base URI does not match the service base URI at line '%1$s'.
- 
+
-BatchSerializerExecption.MISSING_CONTENT_ID=Each request within a change set required exactly one content id.
+BatchSerializerExecption.MISSING_CONTENT_ID=Each request within a change set requires exactly one content id.
 
 PreconditionException.MISSING_HEADER=The Operation you requested on this Entity requires an if-match or if-none-match header.
 PreconditionException.FAILED=The If-Match precondition is not fulfilled.

lib/server-core/src/test/java/org/apache/olingo/server/core/deserializer/batch/BatchRequestParserTest.java

@@ -393,7 +393,7 @@ public class BatchRequestParserTest {
   }
 
   @Test
-  public void testMimeHeaderContentType() throws Exception {
+  public void mimeHeaderContentType() throws Exception {
     final String batch = "--batch_8194-cf13-1f56" + CRLF
         + "Content-Type: text/plain" + CRLF
         + "Content-Transfer-Encoding: binary" + CRLF
@@ -403,7 +403,7 @@ public class BatchRequestParserTest {
         + CRLF
         + "--batch_8194-cf13-1f56--";
 
-    parseInvalidBatchBody(batch, BatchDeserializerException.MessageKeys.INVALID_CONTENT_TYPE);
+    parseInvalidBatchBody(batch, BatchDeserializerException.MessageKeys.UNEXPECTED_CONTENT_TYPE);
   }
 
   @Test
@@ -536,7 +536,7 @@ public class BatchRequestParserTest {
   }
 
   @Test
-  public void testNestedChangeset() throws Exception {
+  public void nestedChangeset() throws Exception {
     final String batch = ""
         + "--batch_8194-cf13-1f56" + CRLF
         + "Content-Type: multipart/mixed;boundary=changeset_f980-1cb6-94dd" + CRLF
@@ -559,7 +559,7 @@ public class BatchRequestParserTest {
         + CRLF
         + "--batch_8194-cf13-1f56--";
 
-    parseInvalidBatchBody(batch, BatchDeserializerException.MessageKeys.INVALID_CONTENT_TYPE);
+    parseInvalidBatchBody(batch, BatchDeserializerException.MessageKeys.UNEXPECTED_CONTENT_TYPE);
   }
 
   @Test
@@ -801,7 +801,7 @@ public class BatchRequestParserTest {
   }
 
   @Test
-  public void testNonNumericContentLength() throws Exception {
+  public void nonNumericContentLength() throws Exception {
     final String batch = ""
         + "--batch_8194-cf13-1f56" + CRLF
         + "Content-Type: multipart/mixed; boundary=changeset_f980-1cb6-94dd" + CRLF
@@ -819,7 +819,7 @@ public class BatchRequestParserTest {
         + CRLF
         + "--batch_8194-cf13-1f56--";
 
-    parseInvalidBatchBody(batch, BatchDeserializerException.MessageKeys.INVALID_HEADER);
+    parseInvalidBatchBody(batch, BatchDeserializerException.MessageKeys.INVALID_CONTENT_LENGTH);
   }
 
   @Test

lib/server-core/src/test/java/org/apache/olingo/server/core/serializer/AsyncResponseSerializerTest.java

@@ -34,7 +34,7 @@ public class AsyncResponseSerializerTest {
   private static final String CRLF = "\r\n";
 
   @Test
-  public void testSimpleResponse() throws Exception {
+  public void simpleResponse() throws Exception {
     ODataResponse response = new ODataResponse();
     response.setStatusCode(HttpStatusCode.OK.getStatusCode());
     response.setHeader(HttpHeader.CONTENT_TYPE, ContentType.APPLICATION_JSON.toContentTypeString());
@@ -45,14 +45,14 @@ public class AsyncResponseSerializerTest {
     AsyncResponseSerializer serializer = new AsyncResponseSerializer();
     InputStream in = serializer.serialize(response);
     String result = IOUtils.toString(in);
-    assertEquals("HTTP/1.1 200 OK" + CRLF +
+    assertEquals("HTTP/1.1 200 OK" + CRLF
-        "Content-Length: 200" + CRLF +
+        + "Content-Type: application/json" + CRLF
-        "Content-Type: application/json" + CRLF + CRLF +
+        + "Content-Length: 200" + CRLF + CRLF
-        "Walter Winter" + CRLF, result);
+        + "Walter Winter" + CRLF, result);
   }
 
   @Test
-  public void testBiggerResponse() throws Exception {
+  public void biggerResponse() throws Exception {
     ODataResponse response = new ODataResponse();
     response.setStatusCode(HttpStatusCode.ACCEPTED.getStatusCode());
     response.setHeader(HttpHeader.CONTENT_TYPE, ContentType.APPLICATION_JSON.toContentTypeString());
@@ -64,10 +64,10 @@ public class AsyncResponseSerializerTest {
     AsyncResponseSerializer serializer = new AsyncResponseSerializer();
     InputStream in = serializer.serialize(response);
     String result = IOUtils.toString(in);
-    assertEquals("HTTP/1.1 202 Accepted" + CRLF +
+    assertEquals("HTTP/1.1 202 Accepted" + CRLF
-        "Content-Length: 0" + CRLF +
+        + "Content-Type: application/json" + CRLF
-        "Content-Type: application/json" + CRLF + CRLF +
+        + "Content-Length: 0" + CRLF + CRLF
-        testData, result);
+        + testData, result);
   }
 
   private String testData(int amount) {