Question

如何使用graph.getVertices()获取特定顶点。

我的班级名称Station已扩展为V（顶点）。
类别＆＃39; （数据类型为LINK）是Station
类别可以是＆＃39;＃12：13＆＃39;或者＆＃39;＃12：14＆＃39;或者＆＃39;＃12：15＆＃39;

我想使用graph.getVertices() JAVA来获取具体的category。

类似的东西：

graph.getVertices("Station category = '#12:13'");

graph.getVertices("Excluded Station Category = '#12:13'");

有什么建议吗？

Answer 1

我使用这个简单的结构来尝试你的案例（category的类型为LINK）：

<强>类：

我使用此代码检索了您要查找的结果：

JAVA代码：

package yourPackage;

import java.io.IOException;

import com.orientechnologies.orient.client.remote.OServerAdmin;
import com.tinkerpop.blueprints.Vertex;
import com.tinkerpop.blueprints.impls.orient.OrientGraph;

public class YourClass{
    private static String remote = "remote:localhost/";
    public static void main(String[] args) {
        String DBname = "yourDBname";
        String currentPath = remote + DBname;
        OServerAdmin serverAdmin;
        try {
            serverAdmin = new OServerAdmin(currentPath).connect("root", "root");
            if (serverAdmin.existsDatabase()) {
                OrientGraph g = new OrientGraph(currentPath);
                String yourRid = "#13:0";
                Iterable<Vertex> targets = g.getVerticesOfClass("Station");
                System.out.println("Category @rid = " + yourRid);
                System.out.println();
                for (Vertex target : targets) {
                    Vertex category = target.getProperty("category");
                    if (category.getId().toString().equals(yourRid)) {
                        System.out.println("Matched Station: " + target.getProperty("name") + "   Category: "
                            + category.getProperty("name") + " (" + category.getId() + ")");
                        System.out.println();
                } else {
                        System.out.println("Excluded Station: " + target.getProperty("name") + "   Category: "
                            + category.getProperty("name") + " (" + category.getId() + ")");
                    }
                }
            }
            else {
                System.out.println("Database " + DBname + " not found");
            }
            serverAdmin.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

<强>输出：

Category @rid = #13:0

Matched Station: First   Category: category 1 (#13:0)

Excluded Station: Second   Category: category 2 (#13:1)
Excluded Station: Third   Category: category 3 (#13:2)

希望有所帮助

Answer 2

获取Station类的所有顶点，尝试：
g.V('_class','Station')

或按类别字段过滤
g.V('_class','Station').has('category','catvalue 123')

或者如果你有多个匹配：
g.V('_class', 'Station').has('category', T.in,['12:13','12:14'])

或特定ID

g.v('12:13')

查找2个顶点之间是否存在边，可以使用：
g.v(stationVtxId).outE('edge_label').sideEffect{x=it}.inV.filter{it == g.v(catVtxId)}.back(2)

Answer 3

我在类Station

的属性类别中使用了索引

create class Station extends V
create class Category extends V

create property Station.name STRING
create property Station.category LINK Category
create property Category.name STRING

create index Station.category ON Station (category) NOTUNIQUE

insert into category(name) values ("category A") // 13:0
insert into category(name) values ("category B") // 13:1
insert into Station(name,category) values ("Station 1",#13:0)
insert into Station(name,category) values ("Station 2",#13:1)

JAVA

如何使用graph.getVertices（）获取特定的顶点，Java，Oriendtdb

3 个答案: