Preliminary documentation for Ice 3.7.1 Beta. Do not use in production applications. Refer to the space directory for other releases.

The stream classes provide all of the low-level methods necessary for encoding and decoding Ice types. However, it would be tedious and error-prone to manually encode complex Ice types such as classes, structs, and dictionaries using these low-level functions. For this reason, the Slice compiler optionally generates helper methods for streaming complex Ice types.

We will use the following Slice definitions to demonstrate the language mapping:

Slice
module M
{
    sequence<...> Seq;
    dictionary<...> Dict;
    struct S
    {
        ...
    }
    enum E { ... }
    class C
    {
        ...
    }
    interface I
    {
        ...
    }
}

The Slice compiler generates the corresponding helper methods shown below:

C#
namespace M
{
    public sealed class SeqHelper
    {
        public static ...[] read(Ice.InputStream istr);
        public static void write(Ice.OutputStream ostr, ...[] v);
    }

    public sealed class DictHelper
    {
        public static Dictionary<...> read(Ice.InputStream istr);
        public static void write(Ice.OutputStream ostr, Dictionary<...> v);
    }

    public partial struct S
    {
        public static S ice_read(Ice.InputStream istr);
        public static void ice_write(Ice.OutputStream ostr, S v);
        ...
        // Instance methods
        public void ice_read(Ice.InputStream istr);
        public void ice_write(Ice.OutputStream ostr);
    }

    public sealed class EHelper
    {
        public static E read(Ice.InputStream istr);
        public static void write(Ice.OutputStream ostr, E v);
    }

    public sealed class IPrxHelper : ...
    {
        public static IPrx read(Ice.InputStream istr);
        public static void write(Ice.OutputStream ostr, IPrx v);
        ...
    }
}

The IPrxHelper class provides read and write methods for extracting and inserting proxies, respectively. Note that the read method returns a proxy of type IPrx but does not perform the equivalent of a checkedCast to verify that the remote object supports interface I.

No additional code is generated for marshaling instances of class types, such as type C that we defined above. Applications should use OutputStream.writeValue and InputStream.readValue to insert and extract class instances, respectively.

See Also

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