Java和Python接口调用Gremlin中的sack、filter语句

场景：

该方法用于实现多跳路径查询，给定查询条件下的起始实体，找到目标实体类型的实体 

命令行格式：

g.withSack{[:]}{it.clone()}.V().hasLabel('start_label')
.has('name', 'query').until(has('entity_type', 'end_label'))
.repeat(dedup().limit(5).sack{m,v -> m[v.values('entity_type')] = 1; m}
.both().simplePath().has('entity_type')
.filter{it.sack()[it.get().value('entity_type')] != 1}).limit(5);

Java接口格式：

package test;
import com.gridgraph.driver.GridGraphAuthenticationException;
import com.gridgraph.driver.GridGraphSecureCluster;
import org.apache.tinkerpop.gremlin.driver.Client;
import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversalSource;
import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.__;
import org.apache.tinkerpop.gremlin.structure.Vertex;
import org.apache.tinkerpop.gremlin.util.function.Lambda;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

class JavaAPIClient{
    public static void main(String[] args) throws GridGraphAuthenticationException {
        GridGraphSecureCluster cluster = new GridGraphSecureCluster("localhost", 8182, "user", "pass");
        Client client = cluster.connect(true);
        client.submit("GridGraphFactory.openGraph('db');return;");
        GraphTraversalSource g =  cluster.traversal("db");
        List<Vertex> res  = g.<HashMap>withSack(
                Lambda.supplier("new HashMap<>()"),
                Lambda.unaryOperator("m -> (HashMap) m.clone()")).V()
                .hasLabel("start_label").has("name", "query").until(__.has("entity_type", "end_label"))
                .repeat(__.dedup().limit(5).<Map, Vertex>sack(Lambda.biFunction("m, v -> m[v.values('entity_type')] = 1; m")).both()
                        .simplePath().has("entity_type").filter(Lambda.predicate("it.sack()[it.get().value('entity_type')] != 1"))).limit(5).toList();
        System.out.println(res);
        client.close();
        cluster.close();
    }
}

Python接口

from gremlin_python.structure.graph import Graph
from gremlin_python.process.anonymous_traversal import traversal
from gremlin_python.process.graph_traversal import __
from gremlin_python.driver.driver_remote_connection import DriverRemoteConnection
from gremlin_python.driver import client

if __name__ == '__main__':
    client = client.Client('ws://localhost:8182/gremlin', None, username='user', password='pass')
    result_set = client.submit('GridGraphFactory.openGraph("db");g=graph.traversal();return;')
    connection = DriverRemoteConnection('ws://localhost:8182/gremlin', 'gdb',
                                        username='user', password='pass')
    g = traversal().withRemote(connection)
    res = g.withSack(lambda: '[:]', lambda :'it.clone()').V().hasLabel('start_label').has('name', 'query') \
                .until(__.has('entity_type', 'end_label')).repeat(__.dedup().limit(5) \
                        .sack(lambda: "m,v -> m[v.values('entity_type')] = 1; m").both().simplePath() \
                .has('entity_type').filter_(lambda: "it.sack()[it.get().value('entity_type')] != 1")) \
                .limit(5).toList()
    print(res)
    client.close()
    connection.close()

​

 参考资料：

学习Gremlin - 20.结果存取口袋sack_gremlin sack-CSDN博客

tinkerpop/gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/sideEffect/SackTest.java at 3.4.6 · apache/tinkerpop · GitHub

TinkerPop Documentation

「JanusGraph-Gremlin」高级语法sack()局部数据结构_withsack-CSDN博客

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