Fix #29

jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/JSON.java

@@ -161,6 +161,19 @@ public enum Feature
         */
        WRITE_ENUMS_USING_INDEX(false),
 
+       /**
+        * Feature that determines whether Date (and date/time) values
+        * (and Date-based things like {@link java.util.Calendar}s) are to be
+        * serialized as numeric timestamps (true),
+        * or using a textual representation (false)
+        *<p>
+        * Feature is disabled by default, so that date/time values are
+        * serialized as text, NOT timestamp.
+        *
+        * @since 2.7
+        */
+       WRITE_DATES_AS_TIMESTAMP(false),
+
        /**
         * Feature that can be enabled to use "pretty-printing", basic indentation
         * to make resulting JSON easier to read by humans by adding white space

jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/impl/JSONWriter.java

@@ -26,6 +26,8 @@
  */
 public class JSONWriter
 {
+    private final static TimeZone DEFAULT_TIMEZONE = TimeZone.getTimeZone("UTC");
+
     /*
     /**********************************************************************
     /* Blueprint config
@@ -42,15 +44,17 @@ public class JSONWriter
     protected final TreeCodec _treeCodec;
 
     protected final boolean _requireSetter;
-    
+
     /*
     /**********************************************************************
     /* Instance config
     /**********************************************************************
      */
 
     protected final JsonGenerator _generator;
-
+
+    protected final TimeZone _timezone;
+
     /*
     /**********************************************************************
     /* Blueprint construction
@@ -68,6 +72,7 @@ public JSONWriter(int features, TypeDetector td, TreeCodec tc)
         _treeCodec = tc;
         _generator = null;
         _requireSetter = JSON.Feature.WRITE_READONLY_BEAN_PROPERTIES.isDisabled(features);
+        _timezone = DEFAULT_TIMEZONE;
     }
 
     /**
@@ -80,6 +85,7 @@ protected JSONWriter(JSONWriter base, JsonGenerator jgen)
         _treeCodec = base._treeCodec;
         _generator = jgen;
         _requireSetter = JSON.Feature.WRITE_READONLY_BEAN_PROPERTIES.isDisabled(_features);
+        _timezone = DEFAULT_TIMEZONE;
     }
 
     /*
@@ -634,14 +640,21 @@ protected void writeNullField(SerializedString fieldName) throws IOException {
             _generator.writeNull();
         }
     }
-    
+
     protected void writeDateValue(Date v) throws IOException {
-        // TODO: maybe allow serialization using timestamp?
-        writeStringValue(v.toString());
+        if (Feature.WRITE_DATES_AS_TIMESTAMP.isEnabled(_features)) {
+            writeLongValue(v.getTime());
+        } else {
+            writeStringValue(dateToString(v));
+        }
     }
 
     protected void writeDateField(String fieldName, Date v) throws IOException {
-        writeStringField(fieldName, v.toString());
+        if (Feature.WRITE_DATES_AS_TIMESTAMP.isEnabled(_features)) {
+            writeLongField(fieldName, v.getTime());
+        } else {
+            writeStringField(fieldName, dateToString(v));
+        }
     }
 
     protected void writeEnumValue(Enum<?> v) throws IOException {
@@ -721,4 +734,17 @@ protected String keyToString(Object rawKey)
         }
         return String.valueOf(rawKey);
     }
+
+    /**
+     * @since 2.7
+     */
+    protected String dateToString(Date v) {
+        if (v == null) {
+            return "";
+        }
+        // !!! 01-Dec-2015, tatu: Should really use proper DateFormat or something
+        //   since this relies on system-wide defaults, and hard/impossible to
+        //   change easily
+        return v.toString();
+    }
 }

jr-objects/src/test/java/com/fasterxml/jackson/jr/failing/ReadEnumMapTest.java → jr-objects/src/test/java/com/fasterxml/jackson/jr/failing/ReadEnumMap21Test.java

@@ -5,7 +5,8 @@
 import com.fasterxml.jackson.jr.ob.JSON;
 import com.fasterxml.jackson.jr.ob.TestBase;
 
-public class ReadEnumMapTest extends TestBase
+// for [jackson-jr#21]
+public class ReadEnumMap21Test extends TestBase
 {
     enum DEF { D, E, F; }
 

jr-objects/src/test/java/com/fasterxml/jackson/jr/failing/ReadWithCtors25Test.java

@@ -3,6 +3,7 @@
 import com.fasterxml.jackson.jr.ob.JSON;
 import com.fasterxml.jackson.jr.ob.TestBase;
 
+// for [jackson-jr#25], allowing single-int constructors
 public class ReadWithCtors25Test extends TestBase
 {
     static class FromInt1 {

jr-objects/src/test/java/com/fasterxml/jackson/jr/ob/WriteSimpleTest.java

@@ -115,7 +115,7 @@ public void testUnknownType() throws Exception
         }
     }
 
-    // For [Issue#16]
+    // For [jackson-jr#16]
     public void testTypedMaps() throws Exception
     {
         final Address from = new Address("xyz");
@@ -136,4 +136,27 @@ public void testTypedMaps() throws Exception
         assertNotNull(map);
         assertEquals(2, map.size());
     }
+
+    // For [jackson-jr#29]
+    public void testSimpleDates() throws Exception
+    {
+        final Date input = new Date(0L);
+        JSON j = JSON.std;
+
+        assertFalse(j.isEnabled(Feature.WRITE_DATES_AS_TIMESTAMP));
+
+        String json = j.asString(input);
+        // What to test? For now, accept two variants we may get, depending
+        // on timezone (which we can not, alas, control)
+        if (!json.contains("Dec 31")
+                && !json.contains("Jan 1")) {
+            fail("Invalid output: "+json);
+        }
+
+        j = j.with(Feature.WRITE_DATES_AS_TIMESTAMP);
+        assertTrue(j.isEnabled(Feature.WRITE_DATES_AS_TIMESTAMP));
+
+        json = j.asString(input);
+        assertEquals("0", json);
+    }
 }

release-notes/VERSION

@@ -7,6 +7,9 @@ Project: jackson-jr
 2.7.0 (not yet released)
 
 #28: Remove misspelled `JSON.Feature.USE_IS_SETTERS`
+#29: Add `JSON.Feature.WRITE_DATES_AS_TIMESTAMP`, enabling of which allows
+ serialization of `java.util.Date` as long
+ (suggested by Giulio P (gpiancastelli@github))
 #31: Fix failure writing UUID, URL and URI
  (reported by Mitsunori K (komamitsu@github))