QPID-9

Added ability to send NULL Strings. EncodingUtils.java now returns an empty string for a zero lengthed String.
To send a null string use prefix 'n'
MapMessageTest.java - Updated to test emptyString and nullString behave correctly.

git-svn-id: https://svn.apache.org/repos/asf/incubator/qpid/trunk/qpid@486574 13f79535-47bb-0310-9956-ffa450edef68

3 files changed, 23 insertions, 7 deletions

diff --git a/java/client/src/test/java/org/apache/qpid/test/unit/basic/MapMessageTest.java b/java/client/src/test/java/org/apache/qpid/test/unit/basic/MapMessageTest.java
index 24cc1b6259..1a469c1d12 100644
--- a/java/client/src/test/java/org/apache/qpid/test/unit/basic/MapMessageTest.java
+++ b/java/client/src/test/java/org/apache/qpid/test/unit/basic/MapMessageTest.java
@@ -1170,9 +1170,7 @@ public class MapMessageTest extends TestCase implements MessageListener
 
         //Check Special values
         assertTrue(m.getString("nullString") == null);
-        assertTrue(m.getString("emptyString") == null);
-        _logger.warn("An emptyString should not become a null string after transmission.");
-        //assertEqual("", m.getString("emptyString"));
+        assertEqual("", m.getString("emptyString"));
     }
 
     private void assertBytesEqual(byte[] expected, byte[] actual)
diff --git a/java/common/src/main/java/org/apache/qpid/framing/EncodingUtils.java b/java/common/src/main/java/org/apache/qpid/framing/EncodingUtils.java
index 0c0b201174..2efdb88fd9 100644
--- a/java/common/src/main/java/org/apache/qpid/framing/EncodingUtils.java
+++ b/java/common/src/main/java/org/apache/qpid/framing/EncodingUtils.java
@@ -343,7 +343,7 @@ public class EncodingUtils
         long length = buffer.getUnsignedInt();
         if (length == 0)
         {
-            return null;
+            return "";
         }
         else
         {
diff --git a/java/common/src/main/java/org/apache/qpid/framing/PropertyFieldTable.java b/java/common/src/main/java/org/apache/qpid/framing/PropertyFieldTable.java
index f367156e73..e6f5196434 100644
--- a/java/common/src/main/java/org/apache/qpid/framing/PropertyFieldTable.java
+++ b/java/common/src/main/java/org/apache/qpid/framing/PropertyFieldTable.java
@@ -52,6 +52,7 @@ public class PropertyFieldTable implements FieldTable, Map
     public static final char LONG_PROPERTY_PREFIX = 'l';
     public static final char FLOAT_PROPERTY_PREFIX = 'f';
     public static final char DOUBLE_PROPERTY_PREFIX = 'd';
+    public static final char NULL_STRING_PROPERTY_PREFIX = 'n';
 
     public static final char STRING_PROPERTY_PREFIX = AMQP_STRING_PROPERTY_PREFIX;
     public static final char CHAR_PROPERTY_PREFIX = AMQP_ASCII_STRING_PROPERTY_PREFIX;
@@ -235,9 +236,11 @@ public class PropertyFieldTable implements FieldTable, Map
         }
         else
         {
+
+
             String type = _propertyNamesTypeMap.get(string);
 
-            if (type == null)
+            if (type == null || type.equals("" + NULL_STRING_PROPERTY_PREFIX))
             {
                 return null;
             }
@@ -345,7 +348,14 @@ public class PropertyFieldTable implements FieldTable, Map
 
     public Object setString(String string, String string1)
     {
-        return put(STRING_PROPERTY_PREFIX + string, string1);
+        if (string1 == null)
+        {
+            return put(NULL_STRING_PROPERTY_PREFIX + string, null);
+        }
+        else
+        {
+            return put(STRING_PROPERTY_PREFIX + string, string1);
+        }
     }
 
     public Object setChar(String string, char c)
@@ -1167,7 +1177,9 @@ public class PropertyFieldTable implements FieldTable, Map
                         buffer.put((byte) DOUBLE_PROPERTY_PREFIX);
                         EncodingUtils.writeDouble(buffer, (Double) value);
                         break;
-
+                    case NULL_STRING_PROPERTY_PREFIX:
+                        buffer.put((byte) NULL_STRING_PROPERTY_PREFIX);
+                        break;
                     case AMQP_WIDE_STRING_PROPERTY_PREFIX:
                         //case AMQP_STRING_PROPERTY_PREFIX:
                     case STRING_PROPERTY_PREFIX:
@@ -1263,6 +1275,9 @@ public class PropertyFieldTable implements FieldTable, Map
                 case STRING_PROPERTY_PREFIX:
                     value = EncodingUtils.readLongString(buffer);
                     break;
+                case NULL_STRING_PROPERTY_PREFIX:
+                    value = null;
+                    break;
                     //case AMQP_ASCII_STRING_PROPERTY_PREFIX:
                 case CHAR_PROPERTY_PREFIX:
                     value = EncodingUtils.readShortString(buffer).charAt(0);
@@ -1345,6 +1360,9 @@ public class PropertyFieldTable implements FieldTable, Map
             case STRING_PROPERTY_PREFIX:
                 encodingSize += EncodingUtils.encodedLongStringLength((String) value);
                 break;
+            case NULL_STRING_PROPERTY_PREFIX:
+                // There is no need for additiona size beyond the prefix 
+                break;
                 //case AMQP_ASCII_STRING_PROPERTY_PREFIX:
             case CHAR_PROPERTY_PREFIX:
                 encodingSize += EncodingUtils.encodedShortStringLength("" + (Character) value);