Research On The HDF Data-Released Platform Based On The Integration Of J2EE And CORBA

How to distribute the huge and valuable remote sensing data to professional terminal clients according to a specific time, specific region and specific waveband rapidly and precisely is a research of quite a practical significance with which the data provider units are faced. The paper targets at the construction and implementation of HDF data distributing platform under Web environment. In this thesis, HDF (Hierarchical data format) and HDF API will be analyzed, and the process of handling MODIS 1B data based on HDF format is also studied. MODIS 1B data mainly includes two HDF data types: SDS and Vdata. SD API and Vdata API are used to deal with the MODIS 1B data. Two distributed structures will be deeply analyzed: J2EE and CORBA. The integration of J2EE and CORBA is also studied. Integration of J2EE and CORBA includes two forms, one is that J2EE device visits CORBA object; the other is that CORBA as the client end transferring the service offered by the EJB devices. Based on web integration belongs to the 1st integration, and it is the study object of the paper, it has two type .one is the 3 tiers Web application based on CORBA, the other is 4 tiers Web application based on CORBA .And the second one will be applied in the system. In this paper, a new frame of using integrated J2EE and CORBA technology for the HDF Data publishing is put forward; it is based on the integration of EJB and CORBA, which can reach technological complement. The HDF data's extracting and downloading is realized under the frame. Its feasibility is test.