TimeValue#parseTimeValue author is bad, feels bad

I stumbled on this code today and I hated it; I wrote it. I did not like
that you could not tell at a glance whether or not the method parameters
were correct. This commit fixes it.

Relates #24522

core/src/main/java/org/elasticsearch/common/unit/TimeValue.java

@@ -254,7 +254,7 @@ public class TimeValue implements Writeable, Comparable<TimeValue> {
      * Returns a {@link String} representation of the current {@link TimeValue}.
      *
      * Note that this method might produce fractional time values (ex 1.6m) which cannot be
-     * parsed by method like {@link TimeValue#parse(String, String, int)}.
+     * parsed by method like {@link TimeValue#parse(String, String, String)}.
      */
     @Override
     public String toString() {
@@ -326,22 +326,20 @@ public class TimeValue implements Writeable, Comparable<TimeValue> {
         }
         final String normalized = sValue.toLowerCase(Locale.ROOT).trim();
         if (normalized.endsWith("nanos")) {
-            return new TimeValue(parse(sValue, normalized, 5), TimeUnit.NANOSECONDS);
+            return new TimeValue(parse(sValue, normalized, "nanos"), TimeUnit.NANOSECONDS);
         } else if (normalized.endsWith("micros")) {
-            return new TimeValue(parse(sValue, normalized, 6), TimeUnit.MICROSECONDS);
+            return new TimeValue(parse(sValue, normalized, "micros"), TimeUnit.MICROSECONDS);
         } else if (normalized.endsWith("ms")) {
-            return new TimeValue(parse(sValue, normalized, 2), TimeUnit.MILLISECONDS);
+            return new TimeValue(parse(sValue, normalized, "ms"), TimeUnit.MILLISECONDS);
         } else if (normalized.endsWith("s")) {
-            return new TimeValue(parse(sValue, normalized, 1), TimeUnit.SECONDS);
+            return new TimeValue(parse(sValue, normalized, "s"), TimeUnit.SECONDS);
         } else if (sValue.endsWith("m")) {
-            // parsing minutes should be case sensitive as `M` is generally
+            // parsing minutes should be case-sensitive as 'M' means "months", not "minutes"; this is the only special case.
-            // accepted to mean months not minutes. This is the only case where
+            return new TimeValue(parse(sValue, normalized, "m"), TimeUnit.MINUTES);
-            // the upper and lower case forms indicate different time units
-            return new TimeValue(parse(sValue, normalized, 1), TimeUnit.MINUTES);
         } else if (normalized.endsWith("h")) {
-            return new TimeValue(parse(sValue, normalized, 1), TimeUnit.HOURS);
+            return new TimeValue(parse(sValue, normalized, "h"), TimeUnit.HOURS);
         } else if (normalized.endsWith("d")) {
-            return new TimeValue(parse(sValue, normalized, 1), TimeUnit.DAYS);
+            return new TimeValue(parse(sValue, normalized, "d"), TimeUnit.DAYS);
         } else if (normalized.matches("-0*1")) {
             return TimeValue.MINUS_ONE;
         } else if (normalized.matches("0+")) {
@@ -355,8 +353,8 @@ public class TimeValue implements Writeable, Comparable<TimeValue> {
         }
     }
 
-    private static long parse(final String initialInput, final String normalized, final int suffixLength) {
+    private static long parse(final String initialInput, final String normalized, final String suffix) {
-        final String s = normalized.substring(0, normalized.length() - suffixLength).trim();
+        final String s = normalized.substring(0, normalized.length() - suffix.length()).trim();
         try {
             return Long.parseLong(s);
         } catch (final NumberFormatException e) {