Minor optimzations to code flow

Author: jtduffy

newrelic-agent/src/main/java/com/newrelic/agent/util/LicenseKeyUtil.java

@@ -9,7 +9,7 @@
 
 import com.newrelic.agent.Agent;
 
-import java.util.Collections;
+import java.util.Arrays;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -33,6 +33,11 @@ public static String obfuscateLicenseKey(String originalString) {
             return originalString;
         }
 
+        // Avoid regex overhead if string doesn't contain "license_key"
+        if (!originalString.contains("license_key")) {
+            return originalString;
+        }
+
         Matcher matcher = LICENSE_KEY_PATTERN.matcher(originalString);
         if (!matcher.find()) {
             return originalString;
@@ -60,10 +65,15 @@ private static String partialObfuscation(String licenseKey) {
         // Otherwise, keep the first 10 characters of the key and replace the
         // remaining key characters with "*"
         if (keyLength > KEY_LENGTH_CUTOFF) {
-            return licenseKey.substring(0, KEY_LENGTH_CUTOFF) +
-                    String.join("", Collections.nCopies(keyLength - KEY_LENGTH_CUTOFF, "*"));
+            return licenseKey.substring(0, KEY_LENGTH_CUTOFF) + createAsterisks(keyLength - KEY_LENGTH_CUTOFF);
         } else {
-            return String.join("", Collections.nCopies(keyLength, "*"));
+            return createAsterisks(keyLength);
         }
     }
+
+    private static String createAsterisks(int count) {
+        char[] asterisks = new char[count];
+        Arrays.fill(asterisks, '*');
+        return new String(asterisks);
+    }
 }

newrelic-agent/src/test/java/com/newrelic/agent/util/LicenseKeyUtilTest.java

@@ -37,7 +37,9 @@ public void testObfuscateLicenseKey() {
         serviceManager.setConfigService(configService);
 
         // When
+        long startTime = System.nanoTime();
         String actualRequestUrl = LicenseKeyUtil.obfuscateLicenseKey(originalRequestUrl);
+        System.out.println("Time (ns): " + (System.nanoTime() - startTime));
         String actualJsonPayload = LicenseKeyUtil.obfuscateLicenseKey(originalJsonPayload);
 
         // Then