Platform confrontation developers want their software to run on as many computers as possible. However, things are willing to violate, and they are still a platform for confrontation in front of GIS developers. J2EE has officially renamed Javaee with Java5.0, and Microsoft is also officially released. Net2.0 and integrated development environmental tools Visual Studio 2005. It is. NET is also Java? It is a pretty Java with a flag drum. NET camp, in fact, the answer to the GIS platform developer has already announced, that is! due to. Net and Java have no obvious advantages, but it is only slightly different from the needs of the application and the habitual difference, so Java is provided. NET's dual development interface to meet different needs, it is not difficult to understand. Can be actually supported by Java and. What is easy! It is necessary to know that the emergence of GIS is a matter of last century. Before the appearance of many IT abbreviations, GIS has been applied in urban planning, land management, military and other industries. Decades have accumulated, many code has become a curing asset. The GIS platform developers have experienced the prosperity and drop of the two development languages, the rise and decline of the component era, and now they have to face the challenge of platform confrontation. Also speaking, we should consider some better, more thorough solutions, allow us to find a relatively stable fulcrum in this era. In fact, this problem has already had a better answer, and the method is also very simple, that is, the glory of C / C , realizes the separation of the GIS kernel and the shell to adapt to the changing external world. In fact, this approach is not a patent of a GIS, using C / C writing programs to achieve a writing, compile everywhere. This is also a cross-platform strategy taken by many software. In contrast, whether it is in Java components and COM, it is still very elegant enough to repair the road between Linux and Windows. No accidents, the platform's confrontation will continue in the next few years, developing under this confrontation platform, perhaps the best to show our developers' wisdom.
The global data data is an important cornerstone of GIS, regardless of industry applications, and leaves the data is passive water, no wood. Spatial data is different from business data in other information systems, which can naturally occur in the system operation, it requires special personnel collection, editing, updating, and space data production itself is a growing industry. The rapid development of remote sensing technology, allowing us to get the GIS data constantly expanded, and the storage management of these data is a big problem. GIS needs to manage management data is a global, facing such large data, using the database is a natural choice. We have difficulty splitting geographic information technology and database, and no one has doubtedly using the database, how the focus of the problem is used. Applications are diverse, engineering, photogrammetry, and other techniques or industries have their specific ways of spatial data. If we try to unify a variety of demand to a spatial database solution, this effort is likely to be . Perhaps we need an open, flexible and scalable structure that can be dynamically adapted. The construction library and release techniques of massive video data have formed a climax in 2005. A number of manufacturers in the fields of GIS, remote sensing have launched a special product. Now we can easily browse high resolution remote sensing images in various devices. The size of the image library is also very large, dozens of G's data is sometimes embarrassed and said, the big people in the TB level video library are there. However, various imaging issues have been eclipsed in front of the shocking effects of Google Earth, and a product made in a search-in company has made a regular army who has enmdd her husband for many years in the GIS industry. In fact, network companies such as GIS companies and Google have different profit models, and GIS companies may have technical strength to show three-dimensional earth, but they cannot be just in order to develop products, they must be based on market needs. True to buy a single development product. If you develop a global three-dimensional browsing product is only used to advertise, then this advertising fee is too expensive. Fortunately, there is a new expensive in Google. It is very big for the science work of remote sensing and GIS, and has also improved the enthusiasm of the three-dimensional performance technology of the geographic information system. Volkswagen GIS industry people have always expected to integrate into IT, let GIS walk into thousands of households, let GIS become part of people's daily lives, just like we will send and receive E-mail every day, every day, use word processing software every day. Everyone has this idea is not accidental. After all, we have no matter whether you travel, dating, shopping, as long as you are related to travel, you can't help you. In addition to "Hello, Hello" in the mobile phone call, I am afraid it is "Where are you". Volkswagen geographic information is to provide location information for people's daily lives, solve the "Where", "Where to", "How to Go", this is the representative of Google, Baidu, Sina Local Search Public map service. In the eyes of GIS developers, perhaps public map service technology is not complicated, and experienced developers may consider this quite temptable market. In fact, in addition to the simple and easy-to-use functions of public map services, there are also data acquisition and update channels, and the most important issue: How to make money from public map services? The profit model is that the GIS company looked at the threshold of the public map service, but it was always the root cause of the income. The growth point of profit could not be clearly seen, and the high input and a large number of public relations coordination in the previous period have made this business that has great potential to have strong financial resources and rich IT profit experiences in Google. It should be noted that the scope of mass geographic information services is far from providing a local search business, and all kinds of software in our daily use may be related to the GIS.
For example, you can add a map chat function in an instant messaging tool such as MSN Messenger, QQ, which is convenient for users to meet; such as commercial ads related to location information on mobile phones and other mobile devices. These are all value-added services related to location information, so they have a common name - location-based service (Lbs). LBS looks great, there are many opportunities, but it is not easy to actually run. In addition to the need for operators, the profit model is still the most important factor. Moving map mobile development has formed a potential huge market due to its huge terminal, and has formed a relatively clear industrial chain. The uppermost end is an integrated circuit, communication device and other mobile phone electronic devices producers. The downstream is the application software developer, while connecting application software development and hardware manufacturers are operating system vendors. Similar to online games, the map service business on the phone is mainly mastered in the operator. If China Mobile or Unicom is interested in providing this business, we can go back to this "hello, where you are", you can go back. Currently, China Mobile Value-added services has SMS, MMS / Color E, WAP, Java / Brew and IVR five. The service provided by the mobile operator is mainly concentrated in three text messages, WAP and Kjava. The mobile application market has reached billions of dollars in a global scale, but the business opportunities are also in risk, so the map service on the mobile phone can be a reality or an unknown number. The GIS mobile development area also includes many other important directions. The more typical and mature business is an integrated application of field data acquisition, car navigation, and the positioning system. In fact, talk about mobile GIS development, we can't talk about wireless positioning technology. GPS well known is a positioning means, in fact, there are still many other positioning methods. For example, using wireless local area network positioning, mobile communication base station positioning, cable television desk network can also provide location information. These positioning methods can compensate for the shortcomings that GPS cannot be applied in the indoor environment, thereby providing a broader space for mobile geographic information service services. Open source pursuits and commercial GIS development fields filled with money, open source GIS world seems simple and quiet, and is the paradise of technical enthusiasts. Open the Source Forge website, on the download list TOP10, we will find a GIS door class software - World Wind. This is written by NASA, written with C #, and calls Microsoft SQL Server Image Library Terrain Server to make global terrain 3D display software and Google Earth very similar. Since the three-dimensional earth simulation has a powerful visual impact, it is never tired of, and the love does not release, so it makes World Wind, this quite professional software is able to be full of electric donkey, eDonkey and other BT download client software Source Forge Top10 list. Unlike commercial GIS software, open source GIS software does not need to carry data compatible, ease of use, and developers can focus on functional development, so open source GIS software is very common, technology is also very advanced, and behind it is from Technical fanators and college graduate students' support. Open source GIS software has now formed a relatively complete product line. Open the www.freegis.org website, we will find a wide range of GIS software. Old card integrated GIS software Grass, Data Conversion Library OGR, GDAL, Map Charge Algor Branch Proj4, Geotrans, also have simple and easy-to-use desktop software Quantum GIS, Map Tools on the Java platform, Map Server is excellent Open Source WEB GIS Software . A variety of spatial analysis, model calculations, especially in the open source GIS field. Dynamic language such as Python is very popular in the open source world. Open source GIS software is no exception, many GIS tools provide a Python interface for system integration.
Python elegant syntax and super strong ability is really a temptation that can't stop. Although the Open Source GIS World is prosperous, its influence is still very small, its identity seems to be a high-profile professional tool in the eyes, and there is no open source GIS tool in the existing Linux release. Open source GIS technology is advanced, but lacks a good ability to meet commercial distribution, therefore involved in the open source GIS field is technical enthusiasts and scientists, and there are less business people to ask. If you can provide a comparative system, an open source GIS solution that meets the commercial requirements, and a stable release is available, as Linux-Apache-MySQL-PHP, the open source GIS future will be unlimited. Open, integration, standards, and interoperability We can regard GIS as a comprehensive and cross-interactive technique associated with many high-tech. It involves the broad, involved, and the trend of technology development is also the benevolence. So, what is the ni meaning behind this complex phenomenon? In fact, it is not difficult to find that GIS is open. Including the opening of the architecture, the opening of the data model, and the opening of our developers' ideas. Only openness can maximize extension ability and flexibility, only openness and application areas, only open to make us more innovation opportunities. And open, it is an important feature of GIS exhibited in the application - integration. GIS has to go out of the laboratory, becoming a technical tool for information construction, has not left various integration. GIS can integrate into business data, can be integrated into the data performance, can be integrated into office software ... Integration ability is GIS's vitality, if you lose the integration of various business systems, GIS can only be reluctant to live, lose Vitality. So how do you guarantee GIS's opening and integration? The key is the standard. Standards and its biological interoperability is a very important issue in the GIS industry. For any geographic information technology or market, consistent and effective standards, you can create opportunities, excitation innovation, increase value, reduce investment cycles, and reduce risks. Not only that, the standard or controlling the high point of the market is the battle for GIS manufacturers, so we are not difficult to understand why everyone is so passionate to set the standard. Another important trend in GIS development is the transition from the software to the service. Especially the outbreak of grid computing concepts since 2001, a single mesh is set off in the field of academia and information technology. There are many in-depth research and discussions for the application of grid in GIS. We have no matter the long-term IT abbreviation written by the grid, first look at the three points of the grid's parent Ian Foster to the grid concept: collaborate non-centralized resources, use standard protocols, High quality service. GIS has not stopped efforts in standard and interoperability in terms of standard and interoperability. When the grid is coming, the GIS industry may be more a smile, because our hearts are very clear about the three main points of Foster, in fact, it has always been the goal pursued by GIS developers.
Spatial database with PostgreSQL / Postgis. The Windows platform uses PostgreSQL's 8.0 Win32 version to get from www.postgresql.org. This version already contains Postgis. POSTGIS is selected during the installation process. Postgis implements the OpenGIS simple feature specification and provides space index. Postgis's official website: http://postgis.refractions.net/. GIS middleware, using geotools, geotools is a mature open source GIS middleware, with a history of nearly 10 years, and there is a certain OpenGIS official background. Get it from www.geotools.org. Geotools adopts Java implementation, and the architecture is very good, easy to expand. Another famous open source software JTS (Java Topology Suite) is used in GEOTOOLS. JTS encapsulates commonly used GEO algorithms and implements OpenGIS's simple feature specification, and also provides memory-based spatial indexes. Web Map Server uses GeOServer. Can be downloaded from http://geoserver.sourceforge.net. GEOSERVER implements the OpenGIS WMS specification and WFS specifications. Install GEOSERVER needs to install Apache or Tomcat. GIS Editor, using another famous GIS open source software JUMP. Can be downloaded from http://www.jump-project.org/. JUMP is based on Java, with plug-in mechanism, easy to expand. Another website http://jump-pilot.sourceforge.net/ provides a plugin with jump. GRASSMAPTOOLS browser end client, you can use JavaScript implementation, or you can implement it with a Java Applet. I chose JavaScript approach, there are many open source implementations on the Internet. I have improved on the simplest basis. Since you use Java programming, recommend Geoserver or Degree, they belong to the open source platform. If the spatial database uses an open source Postgis or MySQL, the development tool uses open source Eclipse to save 20-40W commercial software costs.
