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How to transform CQL into OGC xml filter in Geoserver, aiming at this problem, this article introduces the corresponding analysis and solution in detail, hoping to help more partners who want to solve this problem to find a simpler and easier way.

In the wfs query of Geoserver, the data query filtering of CQL is supported, but the commonly used OGC query is in the form of post and returns the results of the query data by passing the format of a xml file. This can be supported in arcgis server,sfs server because these services support OGC's standard queries.

CQL uses a format similar to text syntax and is highly readable and applicable.

Here is a sample code that uses GeoTools to convert CQL into an OGC filtered query. The specific English URL is in the original link.

GeoTools is an open source java version of gis toolset, in which there are many methods related to gis, you can download the compiled jar package directly online to use.

The conversion code is as follows:

Import java.io.BufferedReader

Import java.io.IOException

Import java.io.InputStreamReader

Import org.geotools.filter.text.cql2.CQL

Import org.geotools.filter.text.cql2.CQLException

Import org.opengis.filter.Filter

Public class CQLToOGC {public static void main (String [] args) throws IOException {BufferedReader reader = new BufferedReader (new InputStreamReader (System.in)); String line; org.geotools.xml.Configuration configuration = new org.geotools.filter.v1_0.OGCConfiguration (); org.geotools.xml.Encoder encoder = new org.geotools.xml.Encoder (configuration); encoder.setIndenting (true) While (! (line = reader.readLine ()). IsEmpty () {try {Filter filter = CQL.toFilter (line); / / System.out.println ("\ t" + filter); encoder.encode (filter, org.geotools.filter.v1_0.OGC.Filter, System.out);} catch (CQLException e) {e.printStackTrace ();}

Result of the conversion:

CQL style

Prop = 23

Conversion result:

Prop 23

The effect of spatial query conversion:

CQL statement:

INTERSECTS (SP_GEOMETRY, POLYGON (142578.64599609 252217.79003906, 73781.897460938 141983.61767578, 287078.38037109 146764.85888672, 142578.64599609 252217.79003906))

Conversion result:

SP_GEOMETRY 142578.64599609 SP_GEOMETRY 252217.79003906 73781.897460938 141983.61767578 287078.38037109 146764.85888672 142578.64599609 252217.79003906 on how to convert CQL into OGC in xml xml filtering questions are shared here, I hope the above content can be of some help to you, if you still have a lot of doubts unsolved, you can follow the industry information channel for more related knowledge.

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