save/restore history upon application stop/start

app/src/main/java/com/tutpro/baresip/History.java

@@ -0,0 +1,24 @@
+package com.tutpro.baresip;
+
+import java.io.Serializable;
+import java.util.GregorianCalendar;
+
+public class History implements Serializable {
+
+    private static final long serialVersionUID = -299482035708790407L;
+
+    private String aor, peer_uri, direction;
+    private GregorianCalendar time;
+
+    public History(String aor, String peer_uri, String direction) {
+            this.aor = aor;
+            this.peer_uri = peer_uri;
+            this.direction = direction;
+            this.time = new GregorianCalendar();
+    }
+
+    public String getAoR() { return aor; }
+    public String getPeerURI() { return peer_uri; }
+    public String getDirection() { return direction; }
+    public GregorianCalendar getTime() { return time; }
+}