altoslib: Store common frequencies in library version-independent form

Serializable Objects in java are very specific to the class being
serialized. As we bump the name of the library on a regular basis to
note API/ABI issues, this mean a saved a Serializable object in
the preferences database will fail to load across library version
upgrades.

The saved tracker state and saved common frequencies were the only
objects saved in this form; this patch adds infrastructure for writing
objects in a version-independent form, and then adds support for
saving frequencies in that form.

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/altoslib/AltosParse.java b/altoslib/AltosParse.java
index ae88182d..12499b7b 100644
--- a/altoslib/AltosParse.java
+++ b/altoslib/AltosParse.java
@@ -53,6 +53,10 @@ public class AltosParse {
 		}
 	}
 
+	public static String format_double_locale(double number) {
+		return nf_locale.format(number);
+	}
+
 	public static double parse_double_net(String str) throws ParseException {
 		try {
 			return nf_net.parse(str.trim()).doubleValue();
@@ -61,6 +65,10 @@ public class AltosParse {
 		}
 	}
 
+	public static String format_double_net(double number) {
+		return nf_net.format(number);
+	}
+
 	public static double parse_coord(String coord) throws ParseException {
 		String[]	dsf = coord.split("\\D+");