altoslib: Make AltosPreferencesBackend abstract. Add set/put Serializable

[fw/altos] / altoslib / AltosFrequency.java

diff --git a/altoslib/AltosFrequency.java b/altoslib/AltosFrequency.java
index 183d45511abd630e7b8e1f1e4f91bfe430df8175..9542fe333858cdac0cbe715db08b1b4001cc41ed 100644 (file)
--- a/altoslib/AltosFrequency.java
+++ b/altoslib/AltosFrequency.java
@@ -17,7 +17,11 @@
 
 package org.altusmetrum.altoslib_10;
 
-public class AltosFrequency {
+import java.io.*;
+import java.util.*;
+import java.text.*;
+
+public class AltosFrequency implements Serializable {
        public double   frequency;
        public String   description;
 
@@ -44,6 +48,10 @@ public class AltosFrequency {
                                     frequency, description);
        }
 
+       public String frequency_string() {
+               return String.format("%7.3f", frequency);
+       }
+
        public boolean close(double f) {
                double  diff = Math.abs(frequency - f);