最近公司的地圖業務數據換了供應商，由于在進行路徑規劃的時候需 要使用到道路結點進行圖的構建，因而需要根據道路圖層提取出道路的節點。因為經常使用arcpy，所以先用python寫了個版本，通常將數據放在地理數據庫中會有更高的運行效率，這里是之前的代碼，并未存到文件地理數據庫中運行，代碼如下：

import arcpy

import time,os

import math

print '程序開始： ' + str(time.ctime())

#設置工作環境 地理數據庫

from arcpy import env

env.workspace = r'E:\data\import'

#新建要素輸出路徑 地理數據庫

out_path = r'E:\data\import'

#輸入要素 地理數據庫中的文件

input_name = 'Road.shp'

start_name = 'Starts.shp'

end_name = 'Ends.shp'

node_name = 'Node.shp'

field_name = 'NodeID'

try:

arcpy.FeatureVerticesToPoints_management(input_name,start_name,"START")

print arcpy.GetMessages()

arcpy.AddField_management(start_name, field_name, "LONG", "", "")

print arcpy.GetMessages()

arcpy.CalculateField_management(start_name, field_name, "!SNodeID!","PYTHON_9.3")

print arcpy.GetMessages()

arcpy.FeatureVerticesToPoints_management(input_name,end_name,"END")

print arcpy.GetMessages()

arcpy.AddField_management(end_name, field_name, "LONG", "", "")

print arcpy.GetMessages()

arcpy.CalculateField_management(end_name, field_name, "!ENodeID!","PYTHON_9.3")

print arcpy.GetMessages()

arcpy.Merge_management([start_name, end_name], node_name)

print arcpy.GetMessages()

arcpy.DeleteIdentical_management(node_name, field_name)

print arcpy.GetMessages()

except Exception as e:

print(e)

finally:

print('Success!')

但是為了和公司保持統一，于是使用java基于geotools又實現了一遍，可視化界面的代碼就不貼了，就放一些節點提取的代碼，以作備份。

/**

* 道路結點提取

*

* @param fileName

*/

private void extractNode(String fileName) throws IOException {

if (Strings.isNullOrEmpty(fileName)) return;

String temp[] = fileName.split("\\\\");

String shpName = "";

if (temp.length > 1) {

for (int j = 0; j < temp.length - 1; j++) {

shpName = shpName + temp[j] + "\\";

}

}

String shpFileName = shpName + "Node.shp";

File newFile =new File(shpFileName);

//設置要生成的shp文件的屬性

//下面是定義要素的字段(屬性)

//第一個參數是要素類型，第二個參數是字段名

//下面對應SHP文件的dbf表中的Shape、name和number字段，FID字段默認生成

//其中srid=4326是定義地理坐標系WGS_84，與ESRI的WKID一樣，因為都是OGC定義的

SimpleFeatureTypeBuilder tb = new SimpleFeatureTypeBuilder();

tb.setCRS(DefaultGeographicCRS.WGS84);

tb.setName("shapefile");

tb.add("the_geom", com.vividsolutions.jts.geom.Point.class);

tb.add("NODEID", Long.class);

//SHP數據存儲工廠

ShapefileDataStoreFactory dataStoreFactory = new ShapefileDataStoreFactory();

//定義生成時的屬性

Map params = new HashMap();

params.put("url", newFile.toURI().toURL());

params.put("create spatial index", Boolean.TRUE);

//生成SHP

ShapefileDataStore newDataStore = (ShapefileDataStore) dataStoreFactory.createNewDataStore(params);

newDataStore.createSchema(tb.buildFeatureType());

newDataStore.setCharset(Charset.forName("GBK"));

//設置Writer

FeatureWriter writer = newDataStore.getFeatureWriter(newDataStore.getTypeNames()[0], Transaction.AUTO_COMMIT);

//加載shapefile

SimpleFeatureSource featureSource = loadShapeFile(fileName);

//檢查shapefile字段信息

checkShapeFileSchema(featureSource.getSchema(), fileName, "SNodeID","ENodeID");

try {

mainController.setStatus("正在進行道路結點提取...");

String finalNodeID = null;

try {

//總筆數

int count = DataUtilities.count(featureSource.getFeatures());

Map map = new HashMap();

//逐筆寫入數據庫

try (SimpleFeatureIterator iterator = featureSource.getFeatures().features()) {

int index = 0;

while (iterator.hasNext()) {

SimpleFeature feature = iterator.next();

Object attribute = feature.getAttribute("SNodeID");

if (attribute != null && !Strings.isNullOrEmpty(attribute.toString()))

finalNodeID = attribute.toString();

Geometry geometry = getNode(feature,"start");

if (geometry != null) {

geometry.setSRID(SRID);

map.put(finalNodeID,geometry);

}

attribute = feature.getAttribute("ENodeID");

if (attribute != null && !Strings.isNullOrEmpty(attribute.toString()))

finalNodeID = attribute.toString();

geometry = getNode(feature,"end");

if (geometry != null) {

geometry.setSRID(SRID);

map.put(finalNodeID,geometry);

}

index++;

}

SimpleFeature newFeature = null;

Iterator iter = map.entrySet().iterator();

while (iter.hasNext()) {

newFeature = writer.next();

Map.Entry entry = (Map.Entry) iter.next();

String key = (String) entry.getKey();

Geometry geom = (Geometry) entry.getValue();

newFeature.setAttribute("NODEID",key);

newFeature.setAttribute("the_geom",geom);

}

writer.write();

writer.close();

newDataStore.dispose();

}

} catch (Exception e) {

throw new IllegalStateException(String.format("shapefile 文件: %s 數據處理出錯!\n錯誤信息: %s", fileName, e.getMessage()), e);

}

} finally {

mainController.setStatus(null);

mainController.setProgress(0);

featureSource.getDataStore().dispose();

}

}

/**

* 根據Feature要素獲取geometry并重新設置geometry

*

*/

private Geometry getNode(SimpleFeature feature,String str){

Geometry geo = (Geometry) feature.getDefaultGeometry();

if(geo == null)

return null;

if (geo == null) return null;

if(geo.getGeometryType().equals("LineString")){

return geometryFactory.createLineString(formatSingleGeometryCorrdinate(geo));

}else if(geo.getGeometryType().equals("MultiLineString")){

return geometryFactory.createPoint(formatMultiLineStringCorrdinate(geo,str));

}else {

return geo;

}

}

最終完成道路結點的提取，隨著需求越來越多，后期會逐步加深對geotools的研究。

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