java list转为数组的用法
List tlist=new ArrayList();
String[] sArray=new String[tlist.size()];
tlist.toArray(sArray);
//geowave 中如下例子:分解多个Geometry json string split char '#'
List<Geometry> geoList=new ArrayList<Geometry>();
String[] geoStrArray=geojson.split("#");
for(String geo_str :geoStrArray)
{
GeoJsonReader gjR=new GeoJsonReader();
Geometry t_geo=gjR.read(geo_str);
geoList.add(t_geo);
System.out.println(geo_str);
}
Geometry[] geoArray=new Geometry[geoList.size()];
geoList.toArray(geoArray);
GeometryFactory geoFact=new GeometryFactory(new PrecisionModel(),srid);
Geometry geoColl=new GeometryCollection(geoArray,geoFact);
//
Geometry geo=geoColl;
hashmap对key排序的用法
//map中的key是没有排序的
Map<String,Double> map=new HashMap<String,Double>();
map.put(fdvalue,area); //添加或修改
map.remove(fdvalue); //删除
//sortMap中的key是已排序的
SortedMap<String,Double> sortMap=new TreeMap<String,Double>(map);
Set<String> keyset=sortMap.keySet();
for (String key : keyset) {
area=sortMap.get(key);
System.out.println(key+"="+area);
}
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