Remove commons codec usage and dependency. (#87)

Author: vjkoskela

pom.xml

@@ -79,7 +79,6 @@
     <aspectjrt.version>1.8.9</aspectjrt.version>
     <cglib.version>3.2.5</cglib.version>
     <client.protocol.version>0.10.0</client.protocol.version>
-    <commons.codec.version>1.10</commons.codec.version>
     <commons.io.version>2.4</commons.io.version>
     <fastutil.version>8.1.1</fastutil.version>
     <findbugs.annotations.version>3.0.1</findbugs.annotations.version>
@@ -603,11 +602,6 @@
       <artifactId>commons-io</artifactId>
       <version>${commons.io.version}</version>
     </dependency>
-    <dependency>
-      <groupId>commons-codec</groupId>
-      <artifactId>commons-codec</artifactId>
-      <version>${commons.codec.version}</version>
-    </dependency>
     <dependency>
       <groupId>org.reflections</groupId>
       <artifactId>reflections</artifactId>

src/main/java/com/arpnetworking/metrics/common/tailer/StatefulTailer.java

@@ -24,7 +24,6 @@
 import com.arpnetworking.utility.Trigger;
 import com.google.common.base.MoreObjects;
 import net.sf.oval.constraint.NotNull;
-import org.apache.commons.codec.binary.Hex;
 import org.apache.commons.io.IOUtils;
 import org.joda.time.Duration;
 
@@ -41,6 +40,7 @@
 import java.security.NoSuchAlgorithmException;
 import java.util.Objects;
 import java.util.Optional;
+import javax.xml.bind.DatatypeConverter;
 
 /**
  * A reimplementation of the Apache Commons IO tailer based on the 2.5 snapshot
@@ -480,7 +480,7 @@ private Optional<String> computeHash(final SeekableByteChannel reader, final int
         // Compute the hash
         _md5.reset();
         final byte[] digest = _md5.digest(buffer.array());
-        final String hash = Hex.encodeHexString(digest);
+        final String hash = DatatypeConverter.printHexBinary(digest);
         LOGGER.trace()
                 .setMessage("Computed hash")
                 .addData("hash", hash)