GeoTools 中的 OpenStreetMap 图层

Question

我正在尝试在地图中为使用 GeoTools 的 Java 应用程序显示 OSM 层作为背景层。

我的出发点是Maven quickstart tutorial 和Tile Client user guide。

因此，我的课程重现我的问题非常简单：

public class OsmMapFrame
{
  public static void main(String args[])
  {
    String baseURL = "https://tile.openstreetmap.org/";
    TileService service = new OSMService("OSM", baseURL);
    MapContent map = new MapContent();
    map.addLayer(new TileLayer(service));
    JMapFrame.showMap(map);
  }
}

当我运行它时，我收到以下错误：

2019-10-28T13:44:15.809+0100  SEVERE  Failed to load image: https://tile.openstreetmap.org/2/3/0.png
java.io.IOException: Can't create an ImageInputStream!
    at org.geotools.image.io.ImageIOExt.read(ImageIOExt.java:339)
    at org.geotools.image.io.ImageIOExt.readBufferedImage(ImageIOExt.java:402)
    at org.geotools.tile.Tile.loadImageTileImage(Tile.java:175)
    at org.geotools.tile.Tile.getBufferedImage(Tile.java:163)
    at org.geotools.tile.util.TileLayer.getTileImage(TileLayer.java:143)
    at org.geotools.tile.util.TileLayer.renderTile(TileLayer.java:131)
    at org.geotools.tile.util.TileLayer.renderTiles(TileLayer.java:125)
    at org.geotools.tile.util.TileLayer.draw(TileLayer.java:86)
    at org.geotools.renderer.lite.CompositingGroup$WrappingDirectLayer.draw(CompositingGroup.java:228)
    at org.geotools.renderer.lite.StreamingRenderer$RenderDirectLayerRequest.execute(StreamingRenderer.java:3850)
    at org.geotools.renderer.lite.StreamingRenderer$PainterThread.run(StreamingRenderer.java:3911)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at java.lang.Thread.run(Thread.java:748)

我假设在我的 pom 中缺少依赖项？目前我在pom.xml 中使用以下 GeoTools 依赖项。

...
        <dependency>
            <groupId>org.geotools</groupId>
            <artifactId>gt-shapefile</artifactId>
            <version>${geotools.version}</version>
        </dependency>
        <dependency>
            <groupId>org.geotools</groupId>
            <artifactId>gt-swing</artifactId>
            <version>${geotools.version}</version>
        </dependency>
        <dependency>
            <groupId>org.geotools</groupId>
            <artifactId>gt-tile-client</artifactId>
            <version>${geotools.version}</version>
        </dependency>
        <dependency>
            <groupId>org.geotools</groupId>
            <artifactId>gt-epsg-hsql</artifactId>
            <version>${geotools.version}</version>
        </dependency>
...

我使用 GeoTools 22.0 和 23-SNAPSHOT 进行了尝试，但在这两种情况下我都得到了以下图片：

Answer 1

我刚刚尝试了你的代码和我的一个旧的 tileviewer，它曾经可以工作，我得到了和你一样的错误。我尝试提高日志记录级别，但这对无用的错误消息没有任何影响！

Java 8 ImageIO 或 OSM 服务图块的方式似乎发生了一些变化。

我尝试了以下代码：

URL url = new URL("https://tile.openstreetmap.org/1/1/0.png");

Iterator<ImageReader> itr = ImageIO.getImageReadersByFormatName("png");
while (itr.hasNext()) {
  ImageReader next = itr.next();
  System.out.println(next.getFormatName());

  next.setInput(url.openStream());
  BufferedImage img = next.read(0);
}

这给了我：

Oct 30, 2019 5:45:18 PM sun.net.www.protocol.http.HttpURLConnection writeRequests
FINE: sun.net.www.MessageHeader@2974f2215 pairs: {GET /1/1/0.png HTTP/1.1: null}{User-Agent: Java/1.8.0_222}{Host: tile.openstreetmap.org}{Accept: text/html, image/gif, image/jpeg, *; q=.2, */*; q=.2}{Connection: keep-alive}
Oct 30, 2019 5:45:18 PM sun.net.www.protocol.http.HttpURLConnection getInputStream0
FINE: sun.net.www.MessageHeader@58fe04997 pairs: {null: HTTP/1.1 429 Too Many Requests}{Server: nginx}{Date: Wed, 30 Oct 2019 17:45:18 GMT}{Content-Type: text/html}{Content-Length: 162}{Connection: keep-alive}{Strict-Transport-Security: max-age=31536000; includeSubDomains; preload}
Exception in thread "main" java.io.IOException: Server returned HTTP response code: 429 for URL: https://tile.openstreetmap.org/1/1/0.png
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1900)
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1498)
    at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:268)
    at java.net.URL.openStream(URL.java:1057)
    at spike.OsmMapFrame.main(OsmMapFrame.java:32)

很明显，有些事情发生了，但我不确定是什么。