java读取SHP的投影信息

要在Java中读取SHP文件的投影信息，可以使用GeoTools库。具体步骤如下：

1. 导入GeoTools库

import org.geotools.data.FileDataStore;
import org.geotools.data.FileDataStoreFinder;
import org.geotools.data.simple.SimpleFeatureSource;
import org.geotools.geometry.jts.ReferencedEnvelope;
import org.opengis.feature.simple.SimpleFeatureType;
import org.opengis.referencing.crs.CoordinateReferenceSystem;

2. 打开SHP文件

File file = new File("your_shapefile.shp");
FileDataStore store = FileDataStoreFinder.getDataStore(file);
SimpleFeatureSource featureSource = store.getFeatureSource();
SimpleFeatureType schema = featureSource.getSchema();

3. 获取投影信息

CoordinateReferenceSystem crs = schema.getCoordinateReferenceSystem();
System.out.println(crs);

这段代码将打印出SHP文件的投影信息。如果你想获取投影的具体参数，可以使用以下代码：

String proj = crs.getName().toString();
System.out.println("Projection: " + proj);

ReferencedEnvelope bounds = featureSource.getBounds();
double[] params = crs.getProjection().getParameters().getValues();
System.out.println("XMin: " + bounds.getMinX());
System.out.println("YMin: " + bounds.getMinY());
System.out.println("XMax: " + bounds.getMaxX());
System.out.println("YMax: " + bounds.getMaxY());

for (int i = 0; i < params.length; i++) {
    System.out.println("Param " + i + ": " + params[i]);
}

这将打印出投影的名称和参数。