Updated OAuth2 token length & secure random algorithm config.

Change-Id: I1c0cd2d7ad6e7c3e5570fae19fa86211a01bfeff
diff --git a/core/src/main/java/de/ids_mannheim/korap/config/KustvaktConfiguration.java b/core/src/main/java/de/ids_mannheim/korap/config/KustvaktConfiguration.java
index 913da7b..eba39a5 100644
--- a/core/src/main/java/de/ids_mannheim/korap/config/KustvaktConfiguration.java
+++ b/core/src/main/java/de/ids_mannheim/korap/config/KustvaktConfiguration.java
@@ -122,7 +122,7 @@
         port = new Integer(properties.getProperty("server.port", "8095"));
         baseURL = properties.getProperty("kustvakt.base.url", "/api/*");
         setSecureRandomAlgorithm(properties
-                .getProperty("security.secure.random.algorithm", "SHA1PRNG"));
+                .getProperty("security.secure.random.algorithm", ""));
         setMessageDigestAlgorithm(
                 properties.getProperty("security.md.algorithm", "MD5"));
     }
diff --git a/core/src/main/java/de/ids_mannheim/korap/encryption/RandomCodeGenerator.java b/core/src/main/java/de/ids_mannheim/korap/encryption/RandomCodeGenerator.java
index ea451aa..fe23f22 100644
--- a/core/src/main/java/de/ids_mannheim/korap/encryption/RandomCodeGenerator.java
+++ b/core/src/main/java/de/ids_mannheim/korap/encryption/RandomCodeGenerator.java
@@ -33,8 +33,15 @@
 
     @PostConstruct
     public void init () throws NoSuchAlgorithmException {
-        secureRandom =
-                SecureRandom.getInstance(config.getSecureRandomAlgorithm());
+        String algorithm = config.getSecureRandomAlgorithm(); 
+        if (!algorithm.isEmpty()) {
+            secureRandom =
+                    SecureRandom.getInstance(algorithm);    
+        }
+        else {
+            secureRandom = new SecureRandom();
+        }
+        System.out.println("Secure random algorithm: "+secureRandom.getAlgorithm());        
     }
 
     public String createRandomCode (KustvaktConfiguration c)