Refactor the SimpleToken factory to move hash function to Sha256Hash.

src/main/java/space/kklochko/spring_rest_example/security/hashes/Sha256Hash.java

@@ -0,0 +1,8 @@
+package space.kklochko.spring_rest_example.security.hashes;
+
+public class Sha256Hash {
+    public String hashOf(String input) {
+        return org.apache.commons.codec.digest.DigestUtils.sha256Hex(input);
+    }
+}
+

src/main/java/space/kklochko/spring_rest_example/security/tokens/SimpleToken.java

@@ -1,8 +1,10 @@
 package space.kklochko.spring_rest_example.security.tokens;
 
+import space.kklochko.spring_rest_example.security.hashes.Sha256Hash;
+
 public class SimpleToken extends StringTokenFactory {
     public String create(String input) {
-        return org.apache.commons.codec.digest.DigestUtils.sha256Hex(input);
+        return (new Sha256Hash()).hashOf(input);
     }
 }
 

src/test/groovy/space/kklochko/spring_rest_example/security/hashes/Sha256HashSpec.groovy

@@ -0,0 +1,27 @@
+package space.kklochko.spring_rest_example.security.hashes
+
+
+import spock.lang.Specification;
+import spock.lang.Subject;
+
+public class Sha256HashSpec extends Specification {
+    def "Create a token that based on sha256"() {
+        given: "I have a hasher"
+        @Subject
+        def hasher = new Sha256Hash()
+
+        when: "I get a hash of a string"
+        String hash = hasher.hashOf(input)
+
+        then: "The token is the same if the same input data."
+        expectedHash == hash
+
+        where: "I have the expected data"
+        input                  || expectedHash
+        "abc"                  || "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad"
+        "random numbers232341" || "7f4b80b2b09ae4326f78b1a9782c807af0a7d0194bffb05602a6585466b4c43e"
+        "admin"                || "8c6976e5b5410415bde908bd4dee15dfb167a9c873fc4bb8a81f6f2ab448a918"
+        "user"                 || "04f8996da763b7a969b1028ee3007569eaf3a635486ddab211d512c85b9df8fb"
+    }
+}
+