The SampleInfo structure contains information associated with each Sample. The DataReader.read() and take() operations return two vectors. One vector contains Sample(s) and the other contains SampleInfo(s). There is a one-to-one correspondence between items in these two vectors. Each Sample is described by the corresponding SampleInfo instance. More...
Public Attributes | |
| uint | sample_state |
| uint | view_state |
| uint | instance_state |
| Time_t | source_timestamp |
| Time_t | reception_timestamp |
| InstanceHandle_t | instance_handle |
| InstanceHandle_t | publication_handle |
| int | disposed_generation_count |
| int | no_writers_generation_count |
| int | sample_rank |
| int | generation_rank |
| int | absolute_generation_rank |
| bool | valid_data |
The SampleInfo structure contains information associated with each Sample. The DataReader.read() and take() operations return two vectors. One vector contains Sample(s) and the other contains SampleInfo(s). There is a one-to-one correspondence between items in these two vectors. Each Sample is described by the corresponding SampleInfo instance.
The generation difference between this sample and the most recent sample. The absolute_generation_rank indicates the generation difference (ie, the number of times the instance was disposed and became alive again) between this sample, and the most recent sample (possibly not in the returned collection) of this instance.
The number of times the instance has become 'ALIVE' after being explicitly disposed. (Computed at the time the sample arrives at the DataReader.)
| int generation_rank |
The generation difference of this sample and the most recent sample in the collection. generation_rank indicates the generation difference (ie, the number of times the instance was disposed and became alive again) between this sample, and the most recent sample in the collection related to this instance.
| InstanceHandle_t instance_handle |
The handle that locally identifies the associated instance.
| uint instance_state |
Indicates whether the associated instance currently exists. instance_state can be one of:
DDS.ALIVE_INSTANCE_STATE
DDS.NOT_ALIVE_DISPOSED_INSTANCE_STATE
DDS.NOT_ALIVE_NO_WRITERS_INSTANCE_STATE
Can use DDS.NOT_ALIVE_INSTANCE_STATE as a test for either 'NOT_ALIVE' state. For example if (sample_info->view_state & DDS.NOT_ALIVE_INSTANCE_STATE) ...
The number of times the instance has become 'ALIVE' after being automatically disposed due to no active writers. (Computed at the time the sample arrives at the DataReader.)
| InstanceHandle_t publication_handle |
The local handle of the source DataWriter.
The time when the sample was received by the DataReader.
| int sample_rank |
Number of samples related to this instances that follow in the collection returned by the DataReader read or take operations.
| uint sample_state |
The associated data sample has/has not been read previously.
sample_state indicates whether or not the DataReader has previously read the associated sample.
One of:
DDS.READ_SAMPLE_STATE
DDS.NOT_READ_SAMPLE_STATE.
Use DDS.ANY_SAMPLE_STATE to test for either state.
The time provided by the DataWriter when the sample was written.
| bool valid_data |
Is set to true if the associated DataSample contains data. The associated DataSample may not contain data if it this sample indicates a change in sample state (for example ALIVE -> DISPOSED).
| uint view_state |
Associated instance has/has not been seen before. view_state indicates whether the DataReader has already seen samples for the most current generation of the related instance.
view_state can be one of:
DDS.NEW_VIEW_STATE
DDS.NOT_NEW_VIEW_STATE
