Source: openjdk-11
Severity: normal
User: reproducible-bui...@lists.alioth.debian.org
Usertags: timestamps toolchain
When writing a properties file using the java.util.Properties class, a header
containing the current date is automatically added. This renders the output non
reproducible.
Here is a patch for java.util.Properties checking if the SOURCE_DATE_EPOCH
environment variable is specified and using it instead of the current date
for the timestamp.
Description: Makes the timestamp in the properties files header reproducible
when SOURCE_DATE_EPOCH is specified
Author: Emmanuel Bourg
Forwarded: no
--- a/src/java.base/share/classes/java/util/Properties.java
+++ b/src/java.base/share/classes/java/util/Properties.java
@@ -905,7 +905,7 @@
if (comments != null) {
writeComments(bw, comments);
}
-bw.write("#" + new Date().toString());
+bw.write("#" + getFormattedTimestamp());
bw.newLine();
synchronized (this) {
for (Map.Entry e : entrySet()) {
@@ -1555,4 +1555,22 @@
}
this.map = map;
}
+
+/**
+ * Returns a formatted timestamp to be used in the properties file header.
+ * The date used is the current date, unless the SOURCE_DATE_EPOCH
+ * environment variable is specified. In this case the format used is
+ * locale and timezone insensitive to ensure the output is reproducible.
+ */
+private String getFormattedTimestamp() {
+if (System.getenv("SOURCE_DATE_EPOCH") == null) {
+return new Date().toString();
+} else {
+// Use the SOURCE_DATE_EPOCH timestamp and make the format
locale/timezone insensitive
+java.text.SimpleDateFormat fmt = new
java.text.SimpleDateFormat("-MM-dd HH:mm:ss z", java.util.Locale.ENGLISH);
+fmt.setTimeZone(java.util.TimeZone.getTimeZone("UTC"));
+Date date = new Date(1000 *
Long.parseLong(System.getenv("SOURCE_DATE_EPOCH")));
+return fmt.format(date);
+}
+}
}
