Micro-optimizations!

1. We were doing some expensive String-building stuff inside calls to logger.debug(), and even when that wasn't our log level we still had to pay the cost. We now check about that before actually building the strings.

2. Simplified string comparison to ignore case rather than explicitly lower-casing, which at least makes the code a little simpler

src/main/java/gov/nih/nlm/nls/metamap/lite/VariantLookupIVF.java

@@ -85,12 +85,18 @@ public int lookupVariant(String term, String word)
       logger.debug("term: " + term);
       logger.debug("word: " + word);
       for (String[] varFields: this.getVariantsForTerm(term.toLowerCase())) {
-	if ((varFields[2].toLowerCase().equals(word.toLowerCase())) ||
-	    (varFields[2].toLowerCase().equals(term.toLowerCase()))) {
+	if ((varFields[2].equalsIgnoreCase(word)) ||
+	    (varFields[2].equalsIgnoreCase(term))) {
 	  variance = Integer.parseInt(varFields[4]); // use varlevel field
-	  logger.debug("*varFields: " + Arrays.stream(varFields).map(i -> i.toString()).collect(Collectors.joining("|")));
+      if (logger.isDebugEnabled()) {
+        // No need to pay for expensive string building operation here unless we actually want to
+        logger.debug("*varFields: " + Arrays.stream(varFields).map(i -> i).collect(Collectors.joining("|")));
+      }
 	} else {
-	  logger.debug(" varFields: " + Arrays.stream(varFields).map(i -> i.toString()).collect(Collectors.joining("|")));
+      if (logger.isDebugEnabled()) {
+        // No need to pay for expensive string building operation here unless we actually want to
+        logger.debug(" varFields: " + Arrays.stream(varFields).map(i -> i).collect(Collectors.joining("|")));
+      }
 	}
       }
     } catch (IOException ioe) {
@@ -104,11 +110,17 @@ public int lookupVariant(String term) {
     try {
       logger.debug("term: " + term);
       for (String[] varFields: this.getVariantsForTerm(term.toLowerCase())) {
-	if ((varFields[2].toLowerCase().equals(term.toLowerCase()))) {
+	if ((varFields[2].equalsIgnoreCase(term))) {
 	  variance = Integer.parseInt(varFields[4]); // use varlevel field
-	  logger.debug("*varFields: " + Arrays.stream(varFields).map(i -> i.toString()).collect(Collectors.joining("|")));
+      if (logger.isDebugEnabled()) {
+        // No need to pay for expensive string building operation here unless we actually want to
+        logger.debug("*varFields: " + Arrays.stream(varFields).map(i -> i).collect(Collectors.joining("|")));
+      }
 	} else {
-	  logger.debug(" varFields: " + Arrays.stream(varFields).map(i -> i.toString()).collect(Collectors.joining("|")));
+      if (logger.isDebugEnabled()) {
+        // No need to pay for expensive string building operation here unless we actually want to
+        logger.debug(" varFields: " + Arrays.stream(varFields).map(i -> i).collect(Collectors.joining("|")));
+      }
 	}
       }
     } catch (IOException ioe) {