1 files changed, 90 insertions, 0 deletions
diff --git a/src/main/model/asn1/GeneralizedTime.java b/src/main/model/asn1/GeneralizedTime.java
new file mode 100644
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+++ b/src/main/model/asn1/GeneralizedTime.java
@@ -0,0 +1,90 @@
+package model.asn1;
+
+import model.asn1.exceptions.ParseException;
+import model.asn1.parsing.BytesReader;
+
+import java.time.ZoneId;
+import java.time.ZonedDateTime;
+import java.time.format.DateTimeFormatter;
+import java.time.format.DateTimeFormatterBuilder;
+import java.time.format.DateTimeParseException;
+import java.time.temporal.ChronoField;
+
+/**
+ * Represents the ASN.1 GeneralizedTime type. It encodes the time in "YYYYMMDDhhmm[ss]Z" string format, in UTC.
+ */
+public class GeneralizedTime extends ASN1Time {
+    /**
+     * The X.680 universal class tag assignment.
+     */
+    public static final Tag TAG = new Tag(TagClass.UNIVERSAL, false, 0x18);
+
+    /**
+     * Rather stupid impl ...
+     */
+    private static final DateTimeFormatter formatterNoSecs = new DateTimeFormatterBuilder()
+            .appendValue(ChronoField.YEAR, 4)
+            .appendValue(ChronoField.MONTH_OF_YEAR, 2)
+            .appendValue(ChronoField.DAY_OF_MONTH, 2)
+            .appendValue(ChronoField.HOUR_OF_DAY, 2)
+            .appendValue(ChronoField.MINUTE_OF_HOUR, 2)
+            .appendLiteral('Z')
+            .toFormatter()
+            .withZone(ZoneId.of("UTC"));
+
+    private static final DateTimeFormatter formatter = new DateTimeFormatterBuilder()
+            .appendValue(ChronoField.YEAR, 4)
+            .appendValue(ChronoField.MONTH_OF_YEAR, 2)
+            .appendValue(ChronoField.DAY_OF_MONTH, 2)
+            .appendValue(ChronoField.HOUR_OF_DAY, 2)
+            .appendValue(ChronoField.MINUTE_OF_HOUR, 2)
+            .optionalStart()
+            .appendValue(ChronoField.SECOND_OF_MINUTE, 2)
+            .optionalEnd()
+            .appendLiteral('Z')
+            .toFormatter()
+            .withZone(ZoneId.of("UTC"));
+
+    /**
+     * EFFECT: Construct the UTCTime with the given tag, parentTag, and timestamp. For tag and parentTag,
+     * consult {@link ASN1Object}.
+     * REQUIRES: timestamp must be in UTC.
+     */
+    public GeneralizedTime(Tag tag, Tag parentTag, ZonedDateTime timestamp) {
+        super(tag, parentTag, timestamp);
+    }
+
+    /**
+     * EFFECT: Parse the given DER input. Time will be assumed to be in UTC.
+     *   Throws {@link ParseException}:
+     *    - The time is not in the string format specified in class specification
+     *    - Other invalid input is found. See {@link ASN1Object} for more details on parsing
+     */
+    public GeneralizedTime(BytesReader encoded, boolean hasParentTag) throws ParseException {
+        super(encoded, hasParentTag);
+    }
+
+    /**
+     * EFFECT: Parse the string into time, in the format specified in class specification.
+     *   Throws {@link ParseException} if the input is malformed.
+     */
+    @Override
+    public ZonedDateTime toDate(String str) throws ParseException {
+        try {
+            return ZonedDateTime.parse(str, formatter);
+        } catch (DateTimeParseException e) {
+            throw new ParseException(e.getMessage());
+        }
+    }
+
+    /**
+     * EFFECT: Convert the time into format "YYYYMMDDhhmm[ss]Z".
+     */
+    @Override
+    public String toString() {
+        if (getTimestamp().getSecond() == 0) {
+            return getTimestamp().format(formatterNoSecs);
+        }
+        return getTimestamp().format(formatter);
+    }
+}