Documentation for Ice 3.4. The latest release is Ice 3.7. Refer to the space directory for other releases.

You are viewing an old version of this page. View the current version.

Compare with Current View Page History

« Previous Version 25 Next »

On this page:

Encoding for General Proxy Parameters

The first component of an encoded proxy is a value of type Ice::Identity. If the proxy is a nil value, the category and name members are empty strings, and no additional data is encoded. The encoding for a non-null proxy consists of general parameters followed by endpoint parameters.

The general proxy parameters are encoded as if they were members of the following structure:

Slice
struct ProxyData {
    Ice::Identity id;
    Ice::StringSeq facet;
    byte mode;
    bool secure;
};

The general proxy parameters are described in the following table.

Parameter

Description

id

The object identity

facet

The facet name (zero- or one-element sequence)

mode

The proxy mode (0=twoway, 1=oneway, 2=batch oneway, 3=datagram, 4=batch datagram)

secure

true if secure endpoints are required, otherwise false

The facet field has either zero elements or one element. An empty sequence denotes the default facet, and a one-element sequence provides the facet name in its first member. If a receiver receives a proxy with a facet field with more than one element, it must throw a ProxyUnmarshalException.

Encoding for Endpoint Parameters

A proxy optionally contains an endpoint list or an adapter identifier, but not both.

  • If a proxy contains endpoints, they are encoded immediately following the general parameters. A size specifying the number of endpoints is encoded first, followed by the endpoints. Each endpoint is encoded as a short specifying the endpoint type (1=TCP, 2=SSL, 3=UDP), followed by an encapsulation of type-specific parameters. The type-specific parameters for TCP, UDP, and SSL are presented in the sections that follow.
  • If a proxy does not have endpoints, a single byte with value 0 immediately follows the general parameters and a string representing the object adapter identifier is encoded immediately following the zero byte.

Type-specific endpoint parameters are encapsulated because a receiver may not be capable of decoding them. For example, a receiver can only decode SSL endpoint parameters if it is configured with the IceSSL plug-in. However, the receiver must be able to re-encode the proxy with all of its original endpoints, in the order they were received, even if the receiver does not understand the type-specific parameters for an endpoint. Encapsulation of the parameters into an opaque endpoint allows the receiver to do this.

Encoding for TCP Endpoint Parameters

A TCP endpoint is encoded as an encapsulation containing the following structure:

Slice
struct TCPEndpointData {
    string host;
    int port;
    int timeout;
    bool compress;
};

The endpoint parameters are described in the following table.

Parameter

Description

host

The server host (a host name or IP address)

port

The server port (1-65535)

timeout

The timeout in milliseconds for socket operations

compress

true if compression should be used (if possible), otherwise false

Encoding for UDP Endpoint Parameters

A UDP endpoint is encoded as an encapsulation containing the following structure:

Slice
struct UDPEndpointData {
    string host;
    int port;
    byte protocolMajor;
    byte protocolMinor;
    byte encodingMajor;
    byte encodingMinor;
    bool compress;
};

The endpoint parameters are described in the following table.

Parameter

Description

host

The server host (a host name or IP address)

port

The server port (1-65535)

protocolMajor

Always set to 1

protocolMinor

Always set to 0

encodingMajor

Always set to 1

encodingMinor

Always set to 0

compress

true if compression should be used (if possible), otherwise false

Encoding for SSL Endpoint Parameters

An SSL endpoint is encoded as an encapsulation containing the following structure:

Slice
struct SSLEndpointData {
    string host;
    int port;
    int timeout;
    bool compress;
};

The endpoint parameters are described in the following table.

Parameter

Description

host

The server host (a host name or IP address)

port

The server port (1-65535)

timeout

The timeout in milliseconds for socket operations

compress

true if compression should be used (if possible), otherwise false

See Also

  • No labels