![cover](https://img-blog.csdnimg.cn/img_convert/1f20816e15694cf3b56262c1f87e2a14.png)
java使用GeoTools,JTS实现叠加分析、提取分析、近邻分析
概念:JTS:JTS Topology Suite (JTS)是一个开源的Java软件库,它提供了平面几何的对象模型和基本的几何函数,符合OGC发布的“Simple Features for SQL”(SFSQL)规范。JTS被设计用作基于矢量地理信息软件的核心组件,还可以用作计算几何的通用算法库。GeoTools:GeoTools 是一个开源 (LGPL) Java 代码库,它为操作地理空间数据
简介
概念:
JTS:JTS Topology Suite (JTS)是一个开源的Java软件库,它提供了平面几何的对象模型和基本的几何函数,符合OGC发布的“Simple Features for SQL”(SFSQL)规范。JTS被设计用作基于矢量地理信息软件的核心组件,还可以用作计算几何的通用算法库。
GeoTools:GeoTools 是一个开源 (LGPL) Java 代码库,它为操作地理空间数据提供符合标准的方法,例如实现地理信息系统。GeoTools 库数据结构基于开放地理空间联盟 (OGC) 规范。
官网地址:
https://www.geotools.org/
你好! 这是你第一次使用 Markdown编辑器 所展示的欢迎页。如果你想学习如何使用Markdown编辑器, 可以仔细阅读这篇文章,了解一下Markdown的基本语法知识。
数据操作
- **shape:
public static void readShpFile(String shpPath) {
File shpFile = new File(shpPath);
try {
ShapefileDataStore shapefileDataStore = new ShapefileDataStore(shpFile.toURI().toURL());
// 设置编码,防止属性的中文字符出现乱码
shapefileDataStore.setCharset(Charset.forName("UTF-8"));
// 这个typeNamae不传递,默认是文件名称
FeatureSource featuresource = shapefileDataStore.getFeatureSource(shapefileDataStore.getTypeNames()[0]);
// 读取bbox
ReferencedEnvelope bbox =featuresource.getBounds();
// 读取投影
CoordinateReferenceSystem crs = featuresource.getSchema().getCoordinateReferenceSystem();
// 特征总数
int count = featuresource.getCount(Query.ALL);
// 获取当前数据的geometry类型(点、线、面)
GeometryType geometryType = featuresource.getSchema().getGeometryDescriptor().getType();
// 读取要素
SimpleFeatureCollection simpleFeatureCollection = (SimpleFeatureCollection) featuresource.getFeatures();
// 获取当前矢量数据有哪些属性字段值
List<AttributeDescriptor> attributes = simpleFeatureCollection.getSchema().getAttributeDescriptors();
// 拿到迭代器
SimpleFeatureIterator simpleFeatureIterator = simpleFeatureCollection.features();
// 遍历每一个要素
while(simpleFeatureIterator.hasNext()) {
SimpleFeature simpleFeature = simpleFeatureIterator.next();
// java8新特性流api
attributes.stream().forEach((a) -> {
// 依次读取这个shape中每一个属性值,当然这个属性值,可以处理其它业务
System.out.println(a.getLocalName() + ":" + simpleFeature.getAttribute(a.getLocalName()));
});
}
} catch (IOException e) {
e.printStackTrace();
}
System.out.println("读取完成!");
}
2. Geoserver服务数据读取
public static final String getFeatureApi = "{{url}}/geoserver/wfs?service=wfs&version=2.0.0&outputFormat=application/json&request=GetFeature&typeNames={{workspace}}:{{layerName}}";
/**
* 获取SimpleFeatureCollection
*/
public static SimpleFeatureCollection getFeature(
String url,
String username,
String password,
String workspace,
String layerName) {
try {
String urlStr = buildUrl(getFeatureApi, url, workspace, layerName);
CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials(username, password));
CloseableHttpClient httpClient = HttpClients.custom().setDefaultCredentialsProvider(credentialsProvider).build();
HttpGet httpGet = new HttpGet(urlStr);
HttpResponse response = httpClient.execute(httpGet);
String jsonStr = EntityUtils.toString(response.getEntity());
ByteArrayInputStream inputStream = new ByteArrayInputStream(jsonStr.getBytes(StandardCharsets.UTF_8));
return (SimpleFeatureCollection) new FeatureJSON().readFeatureCollection(inputStream);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
3. wkt数据读取
// ex : MultiPolygon ( ((10 10, 10 20, 20 20, 20 15, 10 10)), ((60 60, 70 70, 80 60, 60 60 )) )
WKTReader wktReader = new WKTReader();
Geometry geometry = wktReader.read(wktStr);
4. geojson读取
//{“type”:“Feature”,“crs”:{“type”:“name”,“properties”:{“name”:“EPSG:2380”}},“geometry”:{“type”:“MultiPolygon”,“coordinates”:[[[[646398.9535,3267941.9664],[649558.7196,3267895.3528],[649674.763,3265683.4124],[646387.8773,3265827.4858],[646398.9535,3267941.9664]]]]},“properties”:{“Id”:0}}
public static void readGeoJson(String jsonPath) throws IOException {
File file = new File(jsonPath);
FileInputStream fileInputStream = new FileInputStream(file);
// 这里可能存在问题,如果是超大文件怎么办,一次性读入会不会报内存
// 解决方案是不是对大文件进行拆分
GeoJSONReader geoJSONReader = new GeoJSONReader(fileInputStream);
SimpleFeatureCollection featureCollection = geoJSONReader.getFeatures();
SimpleFeatureIterator iterator = featureCollection.features();
List<AttributeDescriptor> attributes = featureCollection.getSchema().getAttributeDescriptors();
while (iterator.hasNext()) {
SimpleFeature simpleFeature = iterator.next();
System.out.println();
attributes.stream().forEach((a) -> {
// 依次读取这个shape中每一个属性值,当然这个属性值,可以处理其它业务
System.out.println(a.getLocalName() + ":" + simpleFeature.getAttribute(a.getLocalName()));
});
}
fileInputStream.close();
System.out.println("读取JSON完毕!");
}
5. 遍历要素及属性
SimpleFeatureCollection simpleFeatureCollection = (SimpleFeatureCollection) featuresource.getFeatures();
// 获取当前矢量数据有哪些属性字段值
List<AttributeDescriptor> attributes = simpleFeatureCollection.getSchema().getAttributeDescriptors();
// 拿到迭代器
SimpleFeatureIterator simpleFeatureIterator = simpleFeatureCollection.features();
// 遍历每一个要素
while(simpleFeatureIterator.hasNext()) {
SimpleFeature simpleFeature = simpleFeatureIterator.next();
// java8新特性流api
attributes.stream().forEach((a) -> {
// 依次读取这个shape中每一个属性值,当然这个属性值,可以处理其它业务
//Object jzmcValue = feature.getAttribute("jzmc");
System.out.println(a.getLocalName() + ":" + simpleFeature.getAttribute(a.getLocalName()));
});
}
6.新增要素(创建图层)
//1.构造TYPE(定义数据的坐标参考、属性字段)
//Class的取值可以是:几何(Point.class,Polygon.class,MultiPolygon.class),属性(String.class,Integer.class, Double.class)
public static SimpleFeatureType createType(Class<?> c, String layerName) {
SimpleFeatureTypeBuilder builder = new SimpleFeatureTypeBuilder();
builder.setCRS(DefaultGeographicCRS.WGS84);
builder.add("FID",String.class);
// 需要注意的是几何字段的属性名称是固定的
builder.add("the_geom", c);
// 设置了图层的名字
builder.setName(layerName);
SimpleFeatureType simpleFeatureType = builder.buildFeatureType();
return simpleFeatureType;
}
//2.根据TYPE构建单个要素
SimpleFeatureBuilder featureBuilder = new SimpleFeatureBuilder(simpleFeatureType);
WKTReader wktReader = new WKTReader();
Geometry geometry = wktReader.read(wktStr);
// 这里的添加顺序和上面TYPE的时候保持一致
featureBuilder.add("1");
featureBuilder.add(geometry);
SimpleFeature feature = featureBuilder.buildFeature(null);
//3.创建FeatureCollection
List<SimpleFeature> features = new ArrayList<>();
// 只需要将上面步骤的单个要素放入循环中创建更多的要素
features.add(feature);
SimpleFeatureCollection collection = new ListFeatureCollection(TYPE, features);
//4. 生成shpfile
File shpFile = new File(shpPath);
ShapefileDataStoreFactory dataStoreFactory = new ShapefileDataStoreFactory();
// 创造shpstore需要的参数
Map<String, Serializable> params = new HashMap<>();
params.put("url", shpFile.toURI().toURL());
params.put("create spatial index", Boolean.TRUE);
ShapefileDataStore newDataStore = (ShapefileDataStore) dataStoreFactory.createNewDataStore(params);
newDataStore.createSchema(simpleFeatureType);
Transaction transaction = new DefaultTransaction("create");
String typeName = newDataStore.getTypeNames()[0];
SimpleFeatureSource featureSource = newDataStore.getFeatureSource(typeName);
SimpleFeatureStore featureStore = (SimpleFeatureStore) featureSource;
SimpleFeatureCollection collection = new ListFeatureCollection(simpleFeatureType, features);
featureStore.setTransaction(transaction);
featureStore.addFeatures(collection);
featureStore.setTransaction(transaction);
transaction.commit();
transaction.close();
7.读取TIFF
public static Coverage readTiff(String tiffPath) throws IOException {
File f = new File(tiffPath);
ParameterValue<OverviewPolicy> policy = AbstractGridFormat.OVERVIEW_POLICY.createValue();
policy.setValue(OverviewPolicy.IGNORE);
ParameterValue<String> gridsize = AbstractGridFormat.SUGGESTED_TILE_SIZE.createValue();
ParameterValue<Boolean> useJaiRead = AbstractGridFormat.USE_JAI_IMAGEREAD.createValue();
useJaiRead.setValue(true);
GridCoverage2D image = new GeoTiffReader(f).read(new GeneralParameterValue[]{policy, gridsize, useJaiRead});
return image;
}
生成TIFF
File file = new File(outTiffPath);
GeoTiffWriter geoTiffWriter = new GeoTiffWriter(file);
final GeoTiffFormat format = new GeoTiffFormat();
final GeoTiffWriteParams wp = new GeoTiffWriteParams();
// 设置写出参数
wp.setCompressionMode(GeoTiffWriteParams.MODE_DEFAULT);
wp.setTilingMode(GeoToolsWriteParams.MODE_DEFAULT);
ParameterValueGroup paramWrite = format.getWriteParameters();
paramWrite.parameter(AbstractGridFormat.GEOTOOLS_WRITE_PARAMS.getName().toString()).setValue(wp);
geoTiffWriter.write((GridCoverage) coverage, paramWrite.values().toArray(new GeneralParameterValue[4]) );
geoTiffWriter.dispose();
空间分析
空间关系(Geometry Relationships):
常见的空间关系(Geometry Relationships)包括:Disjoint、Intersects、Touches、Crosses、Within、Contains、Overlaps、Relates。
空间操作(Geometry Operations):
常见的空间操作(Geometry Operations)包括:Buffer、Intersection、ConvexHull、Intersection、Union、Difference、SymDifference。
裁剪
/**
* 裁剪
*
**/
public static List<String> newClip(GeoserverAnalysisClipDTO dto) {
//获取服务数据
SimpleFeatureCollection collection = GeoServerAnalysisUtils.getFeature(dto.getGeoserverUrl(), dto.getUsername(), dto.getPassword(), dto.getWorkspace(), dto.getLayerName());
// 要裁剪的几何形状
Geometry clipGeometry = SpatialAnalysisUtils.convertToJtsGeometry(dto.getPolygon());
// 创建一个用于存储裁剪后要素的 SimpleFeatureCollection
//DefaultFeatureCollection clippedCollection = new DefaultFeatureCollection();
List<Geometry> list = new ArrayList<>();
// 遍历每个要素
try (SimpleFeatureIterator iterator = collection.features()) {
while (iterator.hasNext()) {
SimpleFeature feature = iterator.next();
// 获取要素的几何属性
Geometry featureGeometry = (Geometry) feature.getDefaultGeometry();
if (featureGeometry.intersects(clipGeometry)) { // 判断要素的几何形状与指定几何形状是否有交集
Geometry intersection = featureGeometry.intersection(clipGeometry);
if (!intersection.isEmpty()) {
// 将交集部分保留下来,作为裁剪后的几何形状
//clippedCollection.add(SimpleFeatureBuilder.build(feature.getFeatureType(), new Object[]{intersection}, null));
list.add(intersection);
}
}
}
}
return geometryToWKT(list);
}
筛选分析
// 筛选分析API接口
public static final String screeningApi = "{{url}}/geoserver/wfs?service=wfs&version=2.0.0&request=GetFeature&outputFormat=application/json&typeNames={{workspace}}:{{layerName}}";
public static String screening( String geoserverUrl, String username,String password,String workspace,String layerName, Map<String, Object> filter) {
try {
String urlStr = buildUrl(screeningApi, geoserverUrl, workspace, layerName);
String filterStr = buildCQLFilter(filter);
urlStr = urlStr + "&" + filterStr;
CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials(username, password));
CloseableHttpClient httpClient = HttpClients.custom().setDefaultCredentialsProvider(credentialsProvider).build();
HttpGet httpGet = new HttpGet(urlStr);
HttpResponse response = httpClient.execute(httpGet);
HttpEntity entity = response.getEntity();
return EntityUtils.toString(entity);
} catch (Exception e) {
e.printStackTrace();
return "后台异常";
}
}
割裂
// 割裂API接口
public static final String splitApi = "{{url}}/geoserver/wfs?service=wfs&version=2.0.0&request=GetFeature&outputFormat=application/json&typeNames={{workspace}}:{{layerName}}&splitField={{splitField}}";
public static String split(String geoserverUrl, String username,String password,String workspace,String layerName,
String splitField) {
try {
String urlStr = buildUrl(splitApi, geoserverUrl, workspace, layerName, splitField);
CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials(username, password));
CloseableHttpClient httpClient = HttpClients.custom().setDefaultCredentialsProvider(credentialsProvider).build();
HttpGet httpGet = new HttpGet(urlStr);
HttpResponse response = httpClient.execute(httpGet);
HttpEntity entity = response.getEntity();
return EntityUtils.toString(entity);
} catch (Exception e) {
e.printStackTrace();
return "后台异常";
}
}
交集
intersection
并集
union
差集
difference
缓冲区
public static String buffer(GeoserverAnalysiBufferDTO dto){
BufferFeatureCollection bf = new BufferFeatureCollection();
SimpleFeatureCollection featureCollection = getFeature(dto.getGeoserverUrl(),dto.getUsername(),dto.getPassword(),dto.getWorkspace(),dto.getLayerName());
//featureCollection.getSchema().getDescriptor();
String[] attributeHeaders = getAttributeHeaders(featureCollection);
// 打印属性字段头
for (String header : attributeHeaders) {
System.out.println(header);
}
SimpleFeatureCollection simpleFeatureCollection = bf.execute(featureCollection, dto.getDistance(), dto.getAttribute());
return Shp2GeojsonUtils.shape2Geojson(simpleFeatureCollection);
}
private static String[] getAttributeHeaders(SimpleFeatureCollection featureCollection) {
// 获取第一个要素
SimpleFeatureIterator iterator = featureCollection.features();
Feature feature = iterator.next();
iterator.close();
// 获取属性字段
List<String> attributeHeaders = new ArrayList<>();
for (Property property : feature.getProperties()) {
String attributeName = property.getName().getLocalPart();
attributeHeaders.add(attributeName);
}
// 将属性字段头转换为字符串数组并返回
return attributeHeaders.toArray(new String[0]);
}
擦除
public static String newErase(GeoserverAnalysisEraseDTO dto) {
SimpleFeatureCollection collection = GeoServerAnalysisUtils.getFeature(dto.getGeoserverUrl(), dto.getUsername(), dto.getPassword(), dto.getWorkspace(), dto.getLayerName());
Geometry oldGeo = SpatialAnalysisUtils.convertToJtsGeometry(dto.getPolygon());
Geometry resultGeo = null;
try (SimpleFeatureIterator iterator = collection.features()) {
while (iterator.hasNext()) {
SimpleFeature feature = iterator.next();
Geometry geometry = (Geometry) feature.getDefaultGeometry();
if (geometry instanceof org.locationtech.jts.geom.Polygon || geometry instanceof org.locationtech.jts.geom.MultiPolygon) {
if (geometry.intersects(oldGeo)) {
Geometry difference = geometry.difference(oldGeo);
if (resultGeo == null) {
resultGeo = difference;
} else {
resultGeo = resultGeo.union(difference);
}
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
WKTWriter writer = new WKTWriter();
return writer.write(resultGeo);
}
点距离
/**
* 两点之间距离计算
* @Date 2024/4/7 15:19
**/
public static double getDistance(double x1, double y1, double x2, double y2) {
// 84坐标系构造GeodeticCalculator
GeodeticCalculator geodeticCalculator = new GeodeticCalculator(DefaultGeographicCRS.WGS84);
// 起点经纬度
geodeticCalculator.setStartingGeographicPoint(x1, y1);
// 末点经纬度
geodeticCalculator.setDestinationGeographicPoint(x2, y2);
// 计算距离,单位:米
return geodeticCalculator.getOrthodromicDistance();
}
近邻分析
public static GeoServerNeighborVO getNeighbor(GeoServerNeighborDTO dto) {
GeoServerNeighborVO vo = new GeoServerNeighborVO();
double miniDist = Double.MAX_VALUE;
SimpleFeatureCollection collection = GeoServerAnalysisUtils.getFeature(dto.getGeoserverUrl(), dto.getUsername(), dto.getPassword(), dto.getWorkspace(), dto.getLayerName());
if (collection != null) {
// 遍历 feature 集合
try (SimpleFeatureIterator iterator = collection.features()) {
while (iterator.hasNext()) {
SimpleFeature feature = iterator.next();
Geometry geometry = (Geometry) feature.getDefaultGeometry();
String jzmc = null;
// 检查几何类型是否为点
if (geometry instanceof org.locationtech.jts.geom.Point) {
Coordinate coordinate = geometry.getCoordinate();
Point point = new Point(coordinate.getX(), coordinate.getY());
// 获取点的坐标
double x = point.getX();
double y = point.getY();
//System.out.println("Point coordinates: (" + x + ", " + y + ")");
//计算距离
double distance = findShort(dto.getPolygon(), point);
if (distance != 0) {
if (distance < miniDist) {
miniDist = distance;
Object jzmcValue = feature.getAttribute("jzmc");
if (jzmcValue != null) {
jzmc = (String) jzmcValue;
}
vo.setPoint(point);
vo.setName(jzmc);
}
}
} else {
System.out.println("This feature is not a point.");
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
vo.setDistance(miniDist * 100);
System.out.println("近邻分析结果:" + vo.toString());
return vo;
}
面邻域
public static List<String> getSquareNeighbor(GeoServerNeighborDTO dto) {
SimpleFeatureCollection collection = GeoServerAnalysisUtils.getFeature(dto.getGeoserverUrl(), dto.getUsername(), dto.getPassword(), dto.getWorkspace(), dto.getLayerName());
Geometry oldGeo = convertToJtsGeometry(dto.getPolygon());
//GeoServerSquareNeighborVO vo = new GeoServerSquareNeighborVO();
List<Geometry> list = new ArrayList<>();
List<String> result = new ArrayList<>();
if (collection == null) {
return result ;
}
try (SimpleFeatureIterator iterator = collection.features()) {
while (iterator.hasNext()) {
SimpleFeature feature = iterator.next();
Geometry geometry = (Geometry) feature.getDefaultGeometry();
if (geometry instanceof org.locationtech.jts.geom.Polygon || geometry instanceof org.locationtech.jts.geom.MultiPolygon) {
// org.locationtech.jts.geom.MultiPolygon multiPolygon = (org.locationtech.jts.geom.MultiPolygon) geometry;
if (geometry.intersects(oldGeo)) {
list.add(geometry);
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
System.out.println("相交:" + geometryToWKT(list));
return geometryToWKT(list);
}
更多推荐
所有评论(0)