Update java.version to 1.8

This was implied by the jclouds 2.3.0 upgrade.  Also address
modernizer warnings.

pom.xml

@@ -307,7 +307,7 @@
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <java.version>1.7</java.version>
+    <java.version>1.8</java.version>
     <jclouds.version>2.3.0</jclouds.version>
     <slf4j.version>1.7.28</slf4j.version>
     <shade.prefix>${project.groupId}.shaded</shade.prefix>

src/main/java/org/gaul/s3proxy/AwsSignature.java

@@ -23,6 +23,7 @@ import java.security.InvalidKeyException;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 import java.util.ArrayList;
+import java.util.Base64;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
@@ -174,7 +175,7 @@ final class AwsSignature {
         } catch (InvalidKeyException | NoSuchAlgorithmException e) {
             throw new RuntimeException(e);
         }
-        return BaseEncoding.base64().encode(mac.doFinal(
+        return Base64.getEncoder().encodeToString(mac.doFinal(
                 stringToSign.getBytes(StandardCharsets.UTF_8)));
     }
 

src/main/java/org/gaul/s3proxy/S3ProxyHandler.java

@@ -34,12 +34,14 @@ import java.security.NoSuchAlgorithmException;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.ArrayList;
+import java.util.Base64;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Date;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.SortedMap;
 import java.util.TimeZone;
@@ -60,7 +62,6 @@ import javax.xml.stream.XMLStreamWriter;
 import com.fasterxml.jackson.core.JsonParseException;
 import com.fasterxml.jackson.dataformat.xml.XmlMapper;
 import com.google.common.base.CharMatcher;
-import com.google.common.base.Optional;
 import com.google.common.base.Splitter;
 import com.google.common.base.Strings;
 import com.google.common.cache.Cache;
@@ -254,7 +255,7 @@ public class S3ProxyHandler {
             };
         }
         this.authenticationType = authenticationType;
-        this.virtualHost = Optional.fromNullable(virtualHost);
+        this.virtualHost = Optional.ofNullable(virtualHost);
         this.maxSinglePartObjectSize = maxSinglePartObjectSize;
         this.v4MaxNonChunkedRequestSize = v4MaxNonChunkedRequestSize;
         this.ignoreUnknownHeaders = ignoreUnknownHeaders;
@@ -1894,7 +1895,7 @@ public class S3ProxyHandler {
         if (contentMD5String != null) {
             try {
                 contentMD5 = HashCode.fromBytes(
-                        BaseEncoding.base64().decode(contentMD5String));
+                        Base64.getDecoder().decode(contentMD5String));
             } catch (IllegalArgumentException iae) {
                 throw new S3Exception(S3ErrorCode.INVALID_DIGEST, iae);
             }
@@ -2107,7 +2108,7 @@ public class S3ProxyHandler {
                 return;
             }
         } else {
-            String expectedSignature = BaseEncoding.base64().encode(
+            String expectedSignature = Base64.getEncoder().encodeToString(
                     hmac("HmacSHA1", policy,
                             credential.getBytes(StandardCharsets.UTF_8)));
             if (!constantTimeEquals(signature, expectedSignature)) {
@@ -2702,7 +2703,7 @@ public class S3ProxyHandler {
         if (contentMD5String != null) {
             try {
                 contentMD5 = HashCode.fromBytes(
-                        BaseEncoding.base64().decode(contentMD5String));
+                        Base64.getDecoder().decode(contentMD5String));
             } catch (IllegalArgumentException iae) {
                 throw new S3Exception(S3ErrorCode.INVALID_DIGEST, iae);
             }