Update HttpOpener Content-Encoding header constant name and JavaDoc. (#513)

Also, group constants.

Author: blackwinter

metafacture-io/src/main/java/org/metafacture/io/HttpOpener.java

@@ -53,24 +53,30 @@
 @FluxCommand("open-http")
 public final class HttpOpener extends DefaultObjectPipe<String, ObjectReceiver<Reader>> {
 
-    public static final String ACCEPT_DEFAULT = "*/*";
     public static final String ACCEPT_HEADER = "accept";
-    public static final String CONTENT_TYPE_HEADER = "content-type";
+    public static final String ACCEPT_CHARSET_HEADER = "accept-charset";
     public static final String ACCEPT_ENCODING_HEADER = "accept-encoding";
-    public static final String ENCODING_HEADER = "content-encoding";
-    public static final String DEFAULT_PREFIX = "ERROR: ";
+    public static final String CONTENT_ENCODING_HEADER = "content-encoding";
+    public static final String CONTENT_TYPE_HEADER = "content-type";
+
+    public static final String ACCEPT_DEFAULT = "*/*";
     public static final String CHARSET_DEFAULT = "UTF-8";
-    public static final String ACCEPT_CHARSET_HEADER = "accept-charset";
+    public static final String DEFAULT_PREFIX = "ERROR: ";
+    public static final String HEADER_FIELD_SEPARATOR = "\n";
+    public static final String HEADER_VALUE_SEPARATOR = ":";
     public static final String INPUT_DESIGNATOR = "@-";
+
     public static final String DEFAULT_METHOD_NAME = "GET";
     public static final Method DEFAULT_METHOD = Method.valueOf(DEFAULT_METHOD_NAME);
-    public static final String HEADER_FIELD_SEPARATOR = "\n";
-    public static final String HEADER_VALUE_SEPARATOR = ":";
+
     private static final Pattern HEADER_FIELD_SEPARATOR_PATTERN = Pattern.compile(HEADER_FIELD_SEPARATOR);
     private static final Pattern HEADER_VALUE_SEPARATOR_PATTERN = Pattern.compile(HEADER_VALUE_SEPARATOR);
+
     private static final int ALLOWED_REDIRECTIONS = 3;
     private static final int CONNECTION_TIMEOUT = 11000;
+
     private final Map<String, String> headers = new HashMap<>();
+
     private Method method;
     private String body;
     private String errorPrefix;
@@ -199,16 +205,16 @@ public void setAcceptContentEncoding(final String contentEncoding) {
     }
 
     /**
-     * Sets the HTTP {@value ENCODING_HEADER} header value. This is the
-     * content encoding for the HTTP GET. It enables HTTP compression.
+     * Sets the HTTP {@value CONTENT_ENCODING_HEADER} header value. This is the
+     * content encoding for the HTTP request. It enables HTTP compression.
      * Allowed values are "gzip".
      * The default for the content encoding is null, which means "no compression".
      *
      * @param contentEncoding name of content encoding used for the content-encoding HTTP
      *                 header
      */
     public void setContentEncoding(final String contentEncoding) {
-        setHeader(ENCODING_HEADER, contentEncoding);
+        setHeader(CONTENT_ENCODING_HEADER, contentEncoding);
     }
 
     /**

metafacture-io/src/test/java/org/metafacture/io/HttpOpenerTest.java

@@ -278,7 +278,7 @@ public void shouldPerformGetRequestWithErrorResponseAndWithoutErrorPrefixParamet
     public void shouldPerformGetRequestWithGzipedContentEncoding() throws IOException {
         shouldPerformRequest(TEST_URL, HttpOpener.Method.GET, (o, u) -> o.setAcceptContentEncoding("gzip"),
                              null, null,
-                             WireMock.ok().withBody(GZIPPED_RESPONSE_BODY).withHeaders(new HttpHeaders(new HttpHeader(HttpOpener.ENCODING_HEADER,"gzip"))),
+                             WireMock.ok().withBody(GZIPPED_RESPONSE_BODY).withHeaders(new HttpHeaders(new HttpHeader(HttpOpener.CONTENT_ENCODING_HEADER,"gzip"))),
                              RESPONSE_BODY);
     }