引入geographiclib类来计算距离，周长和面积的方法

步骤一、引入geographiclib包

	<dependency>
		<groupId>net.sf.geographiclib</groupId>
		<artifactId>GeographicLib-Java</artifactId>
		<version>2.0</version>
	</dependency>

步骤二、分别计算距离，周长和面积

package com.opengis.tools.util;
import net.sf.geographiclib.Geodesic;
import net.sf.geographiclib.GeodesicData;
import net.sf.geographiclib.PolygonArea;
import net.sf.geographiclib.PolygonResult;

public class ComputePolygonArea {

    private static Geodesic geod = Geodesic.WGS84; //定义坐标系
    private static PolygonResult polygonResult;

    /**
     * 构建polygonResult对象
     * @param polygon_wkt
     */
    private static void getPolygonResult (String polygon_wkt){
        PolygonArea polygonarea = new PolygonArea(geod,false);
        for (String i: polygon_wkt.split(",")){
            String[] point = i.split(" ");
            Double lat = Double.valueOf(point[1]).doubleValue();
            Double lon = Double.valueOf(point[0]).doubleValue();
            polygonarea.AddPoint(lat, lon);
        };
        PolygonResult res = polygonarea.Compute();
        polygonResult = res;
        polygonarea.Clear();
    };

    /**
     * 计算长度,单位米
     * @param srcLat 起点纬度
     * @param srcLon 起点经度
     * @param descLat 终点纬度
     * @param descLon 终点经度
     * @return
     */
    private static double getDistance(double srcLat, double srcLon, double descLat, double descLon) {
        double result = 0.0f;
        try {
            GeodesicData g = geod.Inverse(srcLat, srcLon, descLat, descLon);
            result = g.s12;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return result;

    }

    /**
     *计算周长，单位米
     * @param polygon_wkt
     * @return
     */
    private static double getPerimeter (String polygon_wkt){
        getPolygonResult(polygon_wkt);
        double perimeter = polygonResult.perimeter;
        return perimeter;
    }

    /**
     *计算面积，单位平方公里
     * @param polygon_wkt
     * @return
     */
    private static double getArea (String polygon_wkt){
        getPolygonResult(polygon_wkt);
        double area = Math.abs(polygonResult.area);
        return area;
    }

    public static void main(String[] args){
        String polygon_wkt = new String("106.484265 29.931534,106.484909 29.932492,106.487054 29.931367,106.486293 29.930446,106.484265 29.931534");
        Double per = getPerimeter(polygon_wkt);
        System.out.println("周长: "+per);
        Double aa = getArea(polygon_wkt);
        System.out.println("面积: "+aa);
        System.out.println("两点之间距离: "+getDistance(29.931534,106.484265,29.931367,106.487054));
    }
}

输出结果：
周长: 720.5701485233899
面积: 29300.28374773264
两点之间距离: 269.92055435200126