终于搞定GeoTools对PostGis的操作

终于搞定GeoTools对PostGis的操作

      唉，这几天撒事情都没有做，就搞定了GeoTools的一些bug的删除。2.3版本问题比较多，上次在GT上和Richard聊天，他也对GeoTools目前的状况表示很是不满，但是为了PostGis的推广更顺利（毕竟，大多数使用Postgis的兄台还是在geotools平台上），很多时候很多事情都不是我们能决定的。。。所以只能自己动手去将GeoTools在文档中没有说清楚的，或者无法编译的程序根据新的API从新做一次。
     这几天搞定了GeoTools的PostgisDataStore操作。包含连接、读取、新建、插入等等。其实很多功能比如新建和插入都可以用SQL语句去完成，不过这样做对postgis即将推出的空间索引还是有很大影响的。所以我们没有使用SQL去完成这些工作。
   

/**//*
* POSTGEO
*/
package com.geotools.test;

/** *//**
*
* CopyRight (C) All rights reserved.
* <p>
*
* WuHan Inpoint Information Technology Development,Inc.
* <p>
*
* Author sinoly
* <p>
* Project Name: PostGeo
*
*@version 1.0 2006-11-13
*
* <p>
* Base on : JDK1.5
* <p>
*
*/
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.NoSuchElementException;

import org.apache.log4j.Logger;
import org.geotools.data.FeatureReader;
import org.geotools.data.FeatureResults;
import org.geotools.data.FeatureSource;
import org.geotools.data.FeatureStore;
import org.geotools.data.FeatureWriter;
import org.geotools.data.postgis.PostgisDataStore;
import org.geotools.data.postgis.PostgisDataStoreFactory;
import org.geotools.factory.FactoryRegistryException;
import org.geotools.feature.AttributeType;
import org.geotools.feature.AttributeTypeFactory;
import org.geotools.feature.Feature;
import org.geotools.feature.FeatureType;
import org.geotools.feature.FeatureTypeFactory;
import org.geotools.feature.IllegalAttributeException;
import org.geotools.feature.SchemaException;
import org.geotools.geometry.Geometry;

import com.vividsolutions.jts.geom.LineString;
import com.vividsolutions.jts.io.ParseException;
import com.vividsolutions.jts.io.WKTReader;

publicclass GetPostgisData{
   private static final Logger LOGGER= Logger.getLogger("org.geotools.postgis");

   static PostgisDataStore pgDatastore;
   static PostgisDataStoreFactory factory=new PostgisDataStoreFactory();
   static FeatureSource fsBC;
    @SuppressWarnings("unchecked")
   private static void ConnPostGis(String dbtype,String URL,int port,String database,
        String user,String password){
        Map params= new HashMap();
        params.put("dbtype","postgis");
        params.put("host", URL);
        params.put("port",new Integer(port));
        params.put("database", database);
        params.put("user", user);
        params.put("passwd", password);       
       try {
            pgDatastore=(PostgisDataStore) factory.createDataStore( params );
           if(pgDatastore!=null){
                System.out.println("系统连接到位于："+URL+"的空间数据库"+database+"成功！");
            }else{
                System.out.println("系统连接到位于："+URL+"的空间数据库"+database+"失败！请检查相关参数");
            }
        } catch (IOException e){
            e.printStackTrace();
            System.out.println("系统连接到位于："+URL+"的空间数据库"+database+"失败！请检查相关参数");
        }
    }

   //读取指定类型名的地理特征
   public static void getFeatureSource(String sourceName){
       try {
            fsBC= pgDatastore.getFeatureSource(sourceName);
           //System.out.println(fsBC.getFeatures().size());
        } catch (IOException e){
            e.printStackTrace();
        }       
    }
   //取得POSTGIS中所有的地理图层
   public static void getAllLayers(){
       try {
            String[] typeName= pgDatastore.getTypeNames();
           for(int i=0;i<typeName.length;i++){
                System.out.println(typeName[i]);
            }
        } catch (IOException e){
            e.printStackTrace();
        }
    }
   //获取图层地理元素属性（Feature Attribute）
   public static void getAttribute(){
        FeatureType ftBC=fsBC.getSchema();
        System.out.println(ftBC.getAttributeCount());
       for (int i= 0; i< ftBC.getAttributeCount(); i++){
            AttributeType at= ftBC.getAttributeType( i );
           //判断属性类型是否为可分配的几何对象
           if (!Geometry.class.isAssignableFrom(at.getType()))
                System.out.print(at.getType()+ "\t");
        }
        System.out.println();
       for (int i= 0; i< ftBC.getAttributeCount(); i++){
            AttributeType at= ftBC.getAttributeType( i );
           if (!Geometry.class.isAssignableFrom(at.getType()))
                System.out.print(at.getName()+ "\t");
        }
    }
   
   //从数据容器中读取所有的特征属性
    @SuppressWarnings("deprecation")
   public static void PostGisReading(){
       try {
            FeatureResults fsRU= fsBC.getFeatures();
            FeatureReader reader= fsRU.reader();
           while (reader.hasNext()){
                Feature feature;
               try {
                    feature= reader.next();
                    System.out.print(feature.getID()+ "\t");
                   for (int i= 0; i< feature.getNumberOfAttributes(); i++){
                        Object attribute= feature.getAttribute( i );
                       if (!(attributeinstanceof Geometry))
                            System.out.print(attribute+ "\t");
                    }
                    System.out.println();
                } catch (NoSuchElementException e){
                    e.printStackTrace();
                } catch (IllegalAttributeException e){
                    e.printStackTrace();
                }
            }
            reader.close();
        } catch (IOException e1){
            e1.printStackTrace();
        }
    }
   
   //添加特征值到新的特征对象中。等同于新建一个postgis数据表并向其中插入数据
    @SuppressWarnings("deprecation")
   public static void createFeatures(){
       try {
            AttributeType geom= AttributeTypeFactory.newAttributeType("the_geom",LineString.class);
            AttributeType name= AttributeTypeFactory.newAttributeType("name",String.class);
            FeatureType ftRoad= FeatureTypeFactory.newFeatureType
                                (new AttributeType[]{geom,name},"tem_road");
            WKTReader wktReader= new WKTReader();
           try {
                LineString geometry= (LineString) wktReader.read("LINESTRING (0 0, 10 10)");
                String roadName="武络路";
                pgDatastore.createSchema(ftRoad);
                FeatureWriter aWriter= pgDatastore.getFeatureWriter("tem_road",
                        ((FeatureStore) pgDatastore.getFeatureSource("tem_road")).getTransaction());
               /** *//**如有批量导入数据要求，可使用 org.geotools.data.FeatureStore */
                Feature aNewFeature= aWriter.next();
                aNewFeature.setAttribute("the_geom",geometry);
                aNewFeature.setAttribute("name", roadName);
                aWriter.write();
                aWriter.close();
            } catch (ParseException e){
                e.printStackTrace();
            } catch (IllegalAttributeException e){
                e.printStackTrace();
            } catch (IOException e){
                e.printStackTrace();
            }
        } catch (FactoryRegistryException e){
            e.printStackTrace();
        } catch (SchemaException e){
            e.printStackTrace();
        }
    }
   
   //添加Feature到已知的图层之中
   public static void insertFeatures(String featurename){
        WKTReader wktReader= new WKTReader();
       try {
            LineString geometry= (LineString) wktReader.read("LINESTRING (10 10, 20 20)");
            String roadName="珞瑜路";
            FeatureSource source= pgDatastore.getFeatureSource(featurename);
            FeatureWriter aWriter= pgDatastore.getFeatureWriterAppend(featurename,((FeatureStore) source).getTransaction());
           /** *//**如有批量导入数据要求，可使用 org.geotools.data.FeatureStore */
            Feature feature= aWriter.next();
           try {
                feature.setAttribute("the_geom",geometry);
                feature.setAttribute("name", roadName);
            } catch (IllegalAttributeException e){
               // TODO 自动生成 catch 块
                e.printStackTrace();
            }
            aWriter.write();
            aWriter.close();
        } catch (ParseException e1){
           // TODO 自动生成 catch 块
            e1.printStackTrace();
        } catch (IOException e){
           // TODO 自动生成 catch 块
            e.printStackTrace();
        }

    }
   
   public static void main(String[] args)throws IOException{
        ConnPostGis("","localhost",5432,"navigation","root","to0124@c");
       /**//*读取空间库中所有图层*/
        getAllLayers();
       /**//*读取roads图层的空间库，取得FeatureSource对象，
         * getAttribute()方法用于读取此图层所定义的所有的属性
         * 并通过PostGisReading()方法读取此图层中所有信息*/
        getFeatureSource("roads");
        getAttribute();
        PostGisReading();
       /**//*在空间库中新建一个schema并向表中插入数据*/
        createFeatures();
       /**//*向tem_road图层的空间库中插入一条新的记录*/
        insertFeatures("tem_road");
       /**//*修改空间库记录*/
    }
}

      目前对GeoTools真的有些失望。。。不过作为一个开源中间件，它做到目前这个地位真的除了它推出比较早以外，还得感谢开源社区的帮助，2006年10月份推出的2.2版本其中对WMS中图层的渲染效率的大幅提升就是得益与Richard兄台的绝妙建议。自己也希望能向Richard学习，一个43岁的丹麦程序员，真的让人真的体会到什么叫“Open Mind”。。。过年期间的事情也有了眉目，着力修正shp2pqsql的问题。目前随post安装版推出的这个程序还是有些bug，在中文编码以及容错方面都需要提高。