MongoDB 3.2版本常用代码全整理(3)

原文地址
MongoDB的3.x版本Java驱动相对2.x做了全新的设计，类库和使用方法上有很大区别。例如用Document替换BasicDBObject、通过Builders类构建Bson替代直接输入$命令等，本文整理了基于3.2版本的常用增删改查操作的使用方法。为了避免冗长的篇幅，分为增删改、查询、聚合、地理索引等几部分。

随着移动设备的普及，基于坐标和经纬度的位置查询变得越来越流行，例如查找离当前位置最近的N辆出租车。Mongodb专门针对这种查询建立了地理空间索引:2d和2dsphere索引。2d用于平面基于坐标的位置计算，2dsphere主要用于球体，比如地球，提供了基于弧度的位置计算。

import static com.mongodb.client.model.Indexes.geo2d;  import static com.mongodb.client.model.Indexes.geo2dsphere;  import java.text.ParseException;  import java.util.ArrayList;  import java.util.Arrays;  import java.util.List;  import org.bson.Document;  import com.mongodb.Block;  import com.mongodb.MongoClient;  import com.mongodb.client.FindIterable;  import com.mongodb.client.MongoCollection;  import com.mongodb.client.MongoDatabase;  import com.mongodb.client.model.Filters;  import com.mongodb.client.model.geojson.LineString;  import com.mongodb.client.model.geojson.Point;  import com.mongodb.client.model.geojson.Polygon;  import com.mongodb.client.model.geojson.Position;  public class GeospatialExamples {      public static void main(String[] args) throws ParseException {          MongoClient mongoClient = new MongoClient("localhost", 27017);          MongoDatabase database = mongoClient.getDatabase("lesson");          GeospatialExamples client = new GeospatialExamples(database);          client.show();          mongoClient.close();      }      private MongoDatabase database;      public GeospatialExamples(MongoDatabase database) {          this.database = database;      }      public void show() {          MongoCollection<Document> mc = database.getCollection("people");          mc.drop();          Document doc1 = new Document("name", "tom").append("raid", Arrays.asList(10, 10)).append("gps", new Point(new Position(10, 10)));          Document doc2 = new Document("name", "jone").append("raid", Arrays.asList(10.1, 10)).append("gps", new Point(new Position(10.1, 10)));          Document doc3 = new Document("name", "john").append("raid", Arrays.asList(10, 10.1)).append("gps", new Point(new Position(10, 10.1)));          Document doc4 = new Document("name", "jack").append("raid", Arrays.asList(9.9, 10)).append("gps", new Point(new Position(9.9, 10)));          Document doc5 = new Document("name", "mary").append("raid", Arrays.asList(10, 9.9)).append("gps", new Point(new Position(10, 9.9)));          Document doc6 = new Document("name", "abby").append("raid", Arrays.asList(10.2, 10)).append("gps", new Point(new Position(10.2, 10)));          Document doc7 = new Document("name", "adam").append("raid", Arrays.asList(10.3, 10)).append("gps", new Point(new Position(10.3, 10)));          Document doc8 = new Document("name", "barry").append("raid", Arrays.asList(10.4, 10)).append("gps", new Point(new Position(10.4, 10)));          Document doc9 = new Document("name", "anne").append("raid", Arrays.asList(10.5, 10)).append("gps", new Point(new Position(10.5, 10)));          mc.insertMany(Arrays.asList(doc1, doc2, doc3, doc4, doc5, doc6, doc7, doc8, doc9));          mc.createIndex(geo2d("raid"));          mc.createIndex(geo2dsphere("gps"));          //$geoWithin 匹配任意几何图形内搜索          FindIterable<Document> iterable = mc.find(Filters.geoWithin("raid", new Polygon(Arrays.asList(new Position(10.2, 10), new Position(10, 10.2), new Position(9.8, 10), new Position(10, 9.8), new Position(10.2, 10)))));          printResult("Filters.geoWithin raid", iterable);          //$geoWithinBox 在以左下角和右上角坐标构成方形内搜索          iterable = mc.find(Filters.geoWithinBox("raid", 9.8, 9.8, 10.2, 10.2));          printResult("Filters.geoWithinBox raid", iterable);          //$geoWithinPolygon 在多边形内搜索          List<Double> p1 = new ArrayList<>();          List<Double> p2 = new ArrayList<>();          List<Double> p3 = new ArrayList<>();          p1.add(10d);          p1.add(10d);          p2.add(10.1);          p2.add(10.16);          p3.add(10.2);          p3.add(10d);          List<List<Double>> polygon = Arrays.asList(p1, p2, p3);          iterable = mc.find(Filters.geoWithinPolygon("raid", polygon));          printResult("Filters.geoWithinPolygon raid", iterable);          p2.clear();          p2.add(9.9);          p2.add(10.16);          p3.clear();          p3.add(9.8);          p3.add(10d);          polygon = Arrays.asList(p1, p2, p3);          iterable = mc.find(Filters.geoWithinPolygon("gps", polygon));          printResult("Filters.geoWithinPolygon gps", iterable);          //$geoWithinCenter 在指定圆心和半径的圆形内搜索          iterable = mc.find(Filters.geoWithinCenter("raid", 10d, 10d, 0.25));          printResult("Filters.geoWithinCenter raid", iterable);          //$geoWithinCenterSphere 在球体(地球)上指定圆心和弧度搜索, 例如搜索以[10,10]为中心500米内的文档, 参数为...10d, 10d, 0.5/6371          iterable = mc.find(Filters.geoWithinCenterSphere("gps", 10d, 10d, 11d/6371));          printResult("Filters.geoWithinCenterSphere gps", iterable);          //$geoIntersects          iterable = mc.find(Filters.geoIntersects("gps", new LineString(Arrays.asList(new Position(10, 10.1), new Position(10.1, 10), new Position(10, 9.9)))));          printResult("Filters.geoIntersects gps", iterable);          //$near          iterable = mc.find(Filters.near("gps", new Point(new Position(10, 10)), 20566d, 0d));          printResult("Filters.near gps", iterable);          //$nearSphere          iterable = mc.find(Filters.nearSphere("gps", new Point(new Position(10, 10)), 20566d, 10d));          printResult("Filters.nearSphere gps", iterable);      }      public void printResult(String doing, FindIterable<Document> iterable) {          System.out.println(doing);          iterable.forEach(new Block<Document>() {              public void apply(final Document document) {                  System.out.println(document);              }          });          System.out.println("------------------------------------------------------");          System.out.println();      }  }