update README.md

README.md

@@ -4,11 +4,11 @@ Simple oshdb database driver for opening a connection to ignite or h2 instances.
 
 ## Usage:
 ```java
-   Map<String, String> props = new HashMap<>();
+   Properties props = new Properties();
     //props.put("oshdb", "h2:PATH_TO_H2");
-    props.put("oshdb","ignite:PATH_TO_CFG");
-    props.put("prefix","global");
-    props.put("keytable","jdbc:postgresql://localhost/keytables-${prefix}?user=ohsome&password=secret");
+    props.setProperty("oshdb","ignite:PATH_TO_CFG");
+    props.setProperty("prefix","global");
+    props.setProperty("keytable","jdbc:postgresql://localhost/keytables-${prefix}?user=ohsome&password=secret");
 
     OSHDBDriver.connect(props, oshdb -> {
       try {