// Constructor
public HGridFormat(string mime, HGridReader reader, HGridWriter writer)
{
if (mime.IndexOf(';') >= 0)
{
throw new ArgumentException("mime has semicolon " + mime, "mime");
}
m_strMime = mime;
m_gridReader = reader;
m_gridWriter = writer;
m_registry = new Dictionary <string, HGridFormat>();
m_syncLock = new object();
// The original implmentation had a storage of the generic type aginst the formats - but I see this
// as a distinct issue because:
// 1. if this is not storing a real instance with underlying streams attempts to use it should cause
// issues unless makereader /writer is called with the instance - this makes the interface not well
// designed to oo principals and design patterns - implementation should not hide obvious pitfalls in
// calling
// Solution has been to get the underlying stream and construct a real instance
register(new HGridFormat("text/plain", new HZincReader(reader.BaseStream), new HZincWriter(writer.BaseStream)));
register(new HGridFormat("text/zinc", new HZincReader(reader.BaseStream), new HZincWriter(writer.BaseStream)));
//register(new HGridFormat("text/csv", null, HCsvWriter.class));
register(new HGridFormat("application/json", null, new HJsonWriter(writer.BaseStream)));
}
// Make instance of "writer"; constructor with OutputStream is expected.
public HGridWriter makeWriter(StreamWriter outstm)
{
if (m_gridWriter == null)
{
throw new Exception("Format doesn't support writer: " + m_strMime);
}
try
{
if (m_gridWriter is HZincWriter)
{
m_gridWriter = new HZincWriter(outstm);
}
else if (m_gridWriter is HJsonWriter)
{
m_gridWriter = new HJsonWriter(outstm);
}
return(m_gridWriter);
}
catch (Exception e)
{
throw new Exception("Cannot construct: " + m_gridWriter.GetType() + "(OutputStream)", e);
}
}
