Bug 160184 [API]DataSetID.toString() should return null but return "null"
Description: DataSetID.toString() should return null but return "null" Steps to reproduce: Run below codes: new DataSetID( null, 0, null ).toString(); Expected result: null. Actual result: "null"
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/DataSetID.java
}
			if ( ptr >= offset && buffer[ptr] == '.' )
			{
				
				String strRowId = new String( buffer, ptr + 1, offset + length
						- ptr - 1 );
				long rowId = Long.parseLong( strRowId );
				ptr--; 
				if ( ptr >= offset && buffer[ptr] == '}'
						&& buffer[offset] == '{' )
				{
					
					ptr--;
					offset++;
					if ( ptr >= offset )
					{
						DataSetID parent = parse( buffer, offset, ptr - offset
								+ 1 );
						if ( parent != null )
						{
							return new DataSetID( parent, rowId, queryName );
						}
					}
				}
			}
		}
		return new DataSetID( new String( buffer, offset, length ) );
	}
}