3506: Avoid exception control flow in isUriInetAddress

Port of upstream Guava commit e6003692500352e1ba59eee5c93bc21acb3f46c0
which avoids using exceptions as control flow in Jersey's internal
version of InetAddresses.isUriInetAddress().

This avoids the expense of exception creation that can impede request
throughput, especially under high load, and addresses #3506 and
previously JERSEY-3234.

Author: schlosna

core-common/src/main/java/org/glassfish/jersey/internal/guava/InetAddresses.java

@@ -281,11 +281,11 @@ private static InetAddress bytesToInetAddress(byte[] addr) {
      * however, it requires that IPv6 addresses are surrounded by square brackets.
      *
      * @param hostAddr A RFC 3986 section 3.2.2 encoded IPv4 or IPv6 address
-     * @return an InetAddress representing the address in {@code hostAddr}
-     * @throws IllegalArgumentException if {@code hostAddr} is not a valid
-     *                                  IPv4 address, or IPv6 address surrounded by square brackets
+     * @return an InetAddress representing the address in {@code hostAddr};
+     *         otherwise null if {@code hostAddr} is not a valid IPv4 address,
+     *         or IPv6 address surrounded * by square brackets
      */
-    private static InetAddress forUriString(String hostAddr) {
+    private static InetAddress forUriStringNoThrow(String hostAddr) {
         Preconditions.checkNotNull(hostAddr);
 
         // Decide if this should be an IPv6 or IPv4 address.
@@ -302,8 +302,7 @@ private static InetAddress forUriString(String hostAddr) {
         // Parse the address, and make sure the length/version is correct.
         byte[] addr = ipStringToBytes(ipString);
         if (addr == null || addr.length != expectBytes) {
-            throw new IllegalArgumentException(
-                    String.format("Not a valid URI IP literal: '%s'", hostAddr));
+            return null;
         }
 
         return bytesToInetAddress(addr);
@@ -317,12 +316,7 @@ private static InetAddress forUriString(String hostAddr) {
      * @return {@code true} if the argument is a valid IP URI host
      */
     public static boolean isUriInetAddress(String ipString) {
-        try {
-            forUriString(ipString);
-            return true;
-        } catch (IllegalArgumentException e) {
-            return false;
-        }
+        return forUriStringNoThrow(ipString) != null;
     }
 
     /**