From Java , the keys can retrieved using SafeClient. The code snippet is below :
String keystoreUrl = "http://localhost:8080/safe/safe" ;
Strong[] keyNames = {"key1", "key2" };
SafeClient safeClient = new SafeClient(keystoreUrl);
byte[][] keyValues = safeClient.getValues(keyNames) ;
The class SafeClient is part of safe-core.jar