PKIService: add more general variants of resolveFormat

PKIService.resolveFormat is used to check a media type, or list of
media types (possibly including wildcards) against the default list
of content types understood and produced or processed by Dogtag.

The current variants compare the parameter against a hardcoded list
of supported content types.  However, it would be useful to also
provide general variants that allow the caller to specify both the
candidate type(s) and the valid/accepted types.  This commit adds
those variants.

Related: dogtagpki#3297
Signed-off-by: Fraser Tweedale <ftweedal@redhat.com>

Author: frasertweedale

base/server/src/main/java/com/netscape/cms/servlet/base/PKIService.java

@@ -102,24 +102,60 @@ public static String getBanner() throws IOException {
         return new String(Files.readAllBytes(bannerFile), "UTF-8").trim();
     }
 
+    /**
+     * Return a match for a candidate media type (which may be a wildcard)
+     * against the default list of valid media types.
+     *
+     * @return the matching MediaType or null if no match
+     */
     public static MediaType resolveFormat(MediaType format) {
+        return resolveFormat(format, MESSAGE_FORMATS);
+    }
 
-        if (format == null) return null;
+    /**
+     * Return a match for a candidate media type (which may be a wildcard)
+     * against a list of valid media types.
+     *
+     * @return the matching MediaType or null if no match
+     */
+    public static MediaType resolveFormat(MediaType candidate, List<MediaType> validTypes) {
+        if (candidate == null) return null;
 
-        for (MediaType supportedFormat : MESSAGE_FORMATS) {
-            if (format.isCompatible(supportedFormat)) return supportedFormat;
+        for (MediaType validType : validTypes) {
+            if (candidate.isCompatible(validType)) return validType;
         }
 
         return null;
     }
 
+    /**
+     * Find a match from a list of candidate media types (which may be wildcards)
+     * against the default list of valid media types.
+     *
+     * Candidates are checked in list order.  Quality values ("q" parameter)
+     * are ignored.
+     *
+     * @return the matching MediaType or null if no match
+     */
     public static MediaType resolveFormat(List<MediaType> formats) {
+        return resolveFormat(formats, MESSAGE_FORMATS);
+    }
 
-        if (formats == null) return null;
+    /**
+     * Find a match from a list of candidate media types (which may be wildcards)
+     * against a list of valid media types.
+     *
+     * Candidates are checked in list order.  Quality values ("q" parameter)
+     * are ignored.
+     *
+     * @return the matching MediaType or null if no match
+     */
+    public static MediaType resolveFormat(List<MediaType> candidates, List<MediaType> validTypes) {
+        if (candidates == null) return null;
 
-        for (MediaType acceptableFormat : formats) {
-            MediaType supportedFormat = resolveFormat(acceptableFormat);
-            if (supportedFormat != null) return supportedFormat;
+        for (MediaType candidate : candidates) {
+            MediaType match = resolveFormat(candidate, validTypes);
+            if (match != null) return match;
         }
 
         return null;