Java类判断百度地图上某点是否在多边形区域内

功能需求：订单分类（将每笔订单按照所在区域分类），故根据订单收货地址的经纬度来判断订单所在的商业区

import java.awt.geom.Point2D;
import java.util.ArrayList;
import java.util.List;

/**
 * 根据订单的经纬度归属所在的商业区域
 * @author lee
 * @date: 2017年2月6日 下午2:12:02
 */
public class OrderMapTest {
	
	public static void main(String[] args) {
		// 被检测的经纬度点
		PageData orderLocation = new PageData();
		orderLocation.put("X", "117.228117");
		orderLocation.put("Y", "31.830429");
		// 商业区域（百度多边形区域经纬度集合）
		String partitionLocation = "31.839064_117.219116,31.83253_117.219403,31.828511_117.218146,31.826763_117.219259,31.826118_117.220517,31.822713_117.23586,31.822958_117.238375,31.838512_117.23798,31.839617_117.226194,31.839586_117.222925";
		System.out.println(isInPolygon(orderLocation, partitionLocation));
	}
	
	 /** 
     * 判断当前位置是否在多边形区域内 
     * @param orderLocation 当前点
     * @param partitionLocation 区域顶点
     * @return 
     */  
    public static boolean isInPolygon(PageData orderLocation,String partitionLocation){  
    	
        double p_x =Double.parseDouble(orderLocation.getString("X"));  
        double p_y =Double.parseDouble(orderLocation.getString("Y"));  
        Point2D.Double point = new Point2D.Double(p_x, p_y);  
 
        List pointList= new ArrayList();  
        String[] strList = partitionLocation.split(",");
        
        for (String str : strList){
        	String[] points = str.split("_");
            double polygonPoint_x=Double.parseDouble(points[1]);  
            double polygonPoint_y=Double.parseDouble(points[0]);  
            Point2D.Double polygonPoint = new Point2D.Double(polygonPoint_x,polygonPoint_y);  
            pointList.add(polygonPoint);  
        }  
        return IsPtInPoly(point,pointList);  
    }  
    /** 
     * 返回一个点是否在一个多边形区域内， 如果点位于多边形的顶点或边上，不算做点在多边形内，返回false
     * @param point 
     * @param polygon 
     * @return 
     */  
	public static boolean checkWithJdkGeneralPath(Point2D.Double point, List polygon) {  
		java.awt.geom.GeneralPath p = new java.awt.geom.GeneralPath();  
		Point2D.Double first = polygon.get(0);  
        p.moveTo(first.x, first.y);  
        polygon.remove(0);  
        for (Point2D.Double d : polygon) {  
           p.lineTo(d.x, d.y);  
        }  
        p.lineTo(first.x, first.y);  
        p.closePath();  
        return p.contains(point);  
   }  
   
   /** 
    * 判断点是否在多边形内，如果点位于多边形的顶点或边上，也算做点在多边形内，直接返回true
    * @param point 检测点 
    * @param pts   多边形的顶点 
    * @return      点在多边形内返回true,否则返回false 
    */  
   public static boolean IsPtInPoly(Point2D.Double point, List pts){  
         
       int N = pts.size();  
       boolean boundOrVertex = true; //如果点位于多边形的顶点或边上，也算做点在多边形内，直接返回true  
       int intersectCount = 0;//cross points count of x   
       double precision = 2e-10; //浮点类型计算时候与0比较时候的容差  
       Point2D.Double p1, p2;//neighbour bound vertices  
       Point2D.Double p = point; //当前点  
         
       p1 = pts.get(0);//left vertex          
       for(int i = 1; i <= N; ++i){//check all rays              
           if(p.equals(p1)){  
               return boundOrVertex;//p is an vertex  
           }  
             
           p2 = pts.get(i % N);//right vertex              
           if(p.x < Math.min(p1.x, p2.x) || p.x > Math.max(p1.x, p2.x)){//ray is outside of our interests                  
               p1 = p2;   
               continue;//next ray left point  
           }  
             
           if(p.x > Math.min(p1.x, p2.x) && p.x < Math.max(p1.x, p2.x)){//ray is crossing over by the algorithm (common part of)  
               if(p.y <= Math.max(p1.y, p2.y)){//x is before of ray                      
                   if(p1.x == p2.x && p.y >= Math.min(p1.y, p2.y)){//overlies on a horizontal ray  
                       return boundOrVertex;  
                   }  
                     
                   if(p1.y == p2.y){//ray is vertical                          
                       if(p1.y == p.y){//overlies on a vertical ray  
                           return boundOrVertex;  
                       }else{//before ray  
                           ++intersectCount;  
                       }   
                   }else{//cross point on the left side                          
                       double xinters = (p.x - p1.x) * (p2.y - p1.y) / (p2.x - p1.x) + p1.y;//cross point of y                          
                       if(Math.abs(p.y - xinters) < precision){//overlies on a ray  
                           return boundOrVertex;  
                       }  
                         
                       if(p.y < xinters){//before ray  
                           ++intersectCount;  
                       }   
                   }  
               }  
           }else{//special case when ray is crossing through the vertex                  
               if(p.x == p2.x && p.y <= p2.y){//p crossing over p2                      
                   Point2D.Double p3 = pts.get((i+1) % N); //next vertex                      
                   if(p.x >= Math.min(p1.x, p3.x) && p.x <= Math.max(p1.x, p3.x)){//p.x lies between p1.x & p3.x  
                       ++intersectCount;  
                   }else{  
                       intersectCount += 2;  
                   }  
               }  
           }              
           p1 = p2;//next ray left point  
       }  
         
       if(intersectCount % 2 == 0){//偶数在多边形外  
           return false;  
       } else { //奇数在多边形内  
           return true;  
       }  
   }  
}