java 转换投影 EPSG:900913 到 EPSG:4326
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/2217083/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
java transform projection EPSG:900913 to EPSG:4326
提问by
in the openlayers
we can simple transform EPSG:900913 to EPSG:4326
I'm look for a java lib can do that.
here I found this,
http://www.jhlabs.com/java/maps/proj/index.html
在 openlayers 中，我们可以简单地将 EPSG:900913 转换为 EPSG:4326
我正在寻找一个可以做到这一点的 java lib。
我在这里找到了这个，
http://www.jhlabs.com/java/maps/proj/index.html
but the document is in c++
I don't know how to use it.
但是文档是用c++写的，
我不知道怎么用。
If anyone konw that,
please post a simple code
如果有人知道，
请发布一个简单的代码
回答by trashgod
Jerry Huxtable's delightful Globe Appleton the page you cited is indeed written in Java, as seen in the download. The class com.jhlabs.map.proj.ProjectionFactorycontains a method named fromPROJ4Specification(), which returns a com.jhlabs.map.proj.Projection. You can use the EPSG:900913 parameters specified on the OpenLayers siteto create the desired projection.
您引用的页面上Jerry Huxtable 令人愉快的Globe Applet确实是用 Java 编写的，如下载 中所示。该类com.jhlabs.map.proj.ProjectionFactory包含一个名为 的方法fromPROJ4Specification()，该方法返回一个com.jhlabs.map.proj.Projection. 您可以使用OpenLayers 站点上指定的 EPSG:900913 参数来创建所需的投影。
900913: +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +no_defs
You should also look at OpenMap.
您还应该查看OpenMap。
回答by geographika
Another option is to use the OpenSource GIS Java library GeoTools:
另一种选择是使用 OpenSource GIS Java 库 GeoTools：
Details on the projection classes here:
此处投影类的详细信息：
http://geotools.org/javadocs/org/geotools/referencing/operation/projection/MapProjection.html
http://geotools.org/javadocs/org/geotools/referencing/operation/projection/MapProjection.html
Projection definitions in many different formats for all projections can be downloaded from:
所有投影的许多不同格式的投影定义可以从以下位置下载：
http://www.spatialreference.org/
http://www.spatialreference.org/
回答by disrvptor
Geotoolsis probably the best library to use for this. Taking a look at their CRS tutorial, it looks trivial to transform from one coordinate system to another using:
Geotools可能是用于此目的的最佳库。看看他们的CRS 教程，使用以下方法从一个坐标系转换到另一个坐标系看起来很简单：
CoordinateReferenceSystem dataCRS = schema.getCoordinateReferenceSystem();
CoordinateReferenceSystem worldCRS = map.getCoordinateReferenceSystem();
boolean lenient = true; // allow for some error due to different datums
MathTransform transform = CRS.findMathTransform(dataCRS, worldCRS, lenient);
Your CRS references can be retrieved using:
可以使用以下方法检索您的 CRS 参考：
CRS.decode("EPSG:4326")
Per the javadoc.
根据javadoc。
回答by Jamie
I understand that this is from almost 8 years ago, but maybe this can help another intrepid traveller.
我知道这是近 8 年前的事，但也许这可以帮助另一个勇敢的旅行者。
We had to move away from GeoTools because it's LGPL, which is not allowed by our legal folk.
我们不得不放弃 GeoTools，因为它是 LGPL，我们的法律人员不允许这样做。
I just moved our code to use proj4j (https://trac.osgeo.org/proj4j/). It doesn't look like it's being actively developed, but it works for our simple needs. Also, the license is Apache 2.0, which is much more permissive.
我只是将我们的代码移动到使用 proj4j ( https://trac.osgeo.org/proj4j/)。它看起来并没有被积极开发，但它可以满足我们的简单需求。此外，许可证是 Apache 2.0，它更宽松。
It's available via Maven, so that makes it easy: http://search.maven.org/#artifactdetails%7Corg.osgeo%7Cproj4j%7C0.1.0%7Cjar.
它可以通过 Maven 获得，因此很容易：http: //search.maven.org/#artifactdetails%7Corg.osgeo%7Cproj4j%7C0.1.0%7Cjar。
It doesn't directly support EPSG:900913, since it's not really the official standard. It does support EPSG:3857, which is the same thing.
它不直接支持 EPSG:900913，因为它并不是真正的官方标准。它确实支持 EPSG:3857，这是一回事。
Here's a snippet doing what you're looking for:
这是您正在寻找的代码片段：
public Point2D.Double transform(Point2D.Double point, String sourceCRS, String targetCRS) {
Point2D.Double destPosition = new Point2D.Double();
CRSFactory factory = new CRSFactory();
CoordinateReferenceSystem srcCrs = factory.createFromName(sourceCRS); // Use "EPSG:3857" here instead of 900913.
CoordinateReferenceSystem destCrs = factory.createFromName(targetCRS); // Use "EPSG:4326 here.
CoordinateTransform transform = new CoordinateTransformFactory().createTransform(srcCrs, destCrs);
ProjCoordinate srcCoord = new ProjCoordinate(point.getX(), point.getY());
ProjCoordinate destCoord = new ProjCoordinate();
transform.transform(srcCoord, destCoord);
destPosition.setLocation(destCoord.x, destCoord.y);
return destPosition;
}
回答by pxp
Also interesting: Proj4j
同样有趣：Proj4j
Proj4J is a Java library to transform point coordinates from one geographic coordinate system to another, including datum transformations. The core of this library is a port of the PROJ.4 C library.
Proj4J 是一个 Java 库，用于将点坐标从一个地理坐标系转换为另一个地理坐标系，包括基准面转换。这个库的核心是 PROJ.4 C 库的一个端口。
回答by keesp
There seems to be a new Apache project, which may be a more up to date alternative for the open source projects mentioned above:
似乎有一个新的 Apache 项目，对于上面提到的开源项目，它可能是一个更新的替代方案：
It presents itself as an alternative for proj4:
它表现为 proj4 的替代方案：
