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    3. 使用java操作Neo4j数据库

    使用java操作Neo4j数据库

    技术2024-05-24  77

     

     

    1.引言

    这里的Java操作Neo数据库使用的是嵌入式模式，Neo4j可分为嵌入式模式和服务端模式，两者的区别可以查看方案（https://blog.csdn.net/regan_hoo/article/details/78771888）

    也可以查看《Neo4j实战 》这本书的第10章，上面有详细讲解（需要电子版的可以找我）。

    我们构造一个案件的场景。比如一个案件中有多个嫌疑人，有的嫌疑人参与了多个案件。

    2 程序代码

    pom

    <dependency> <groupId>org.neo4j</groupId> <artifactId>neo4j</artifactId> <version>3.3.5</version> </dependency>

    Java代码

    package neo4j; import org.neo4j.graphdb.*; import org.neo4j.graphdb.factory.GraphDatabaseFactory; import org.neo4j.graphdb.index.Index; import org.neo4j.graphdb.traversal.Evaluators; import org.neo4j.graphdb.traversal.TraversalDescription; import java.io.File; import java.util.Iterator; /** * Created by cgz on 2018-04-17 15:29 * 描述： */ public class CaseInfoAs { // private static final String DB_PATH = "testgraph.db"; private static final String DB_PATH = "E:\\soft\\neo4j-community-3.3.5\\data\\databases\\graph.db"; private GraphDatabaseService graphDB; private enum RelTypes implements RelationshipType { CRIME, LINK } public void init() { graphDB = new GraphDatabaseFactory().newEmbeddedDatabase(new File(DB_PATH)); } /**创建数据*/ public void create() { Transaction tx = graphDB.beginTx(); Node case1 = graphDB.createNode(new CaseLabel("CASEINFO")); case1.setProperty("name", "案件1"); case1.setProperty("address", "南山"); Node case2 = graphDB.createNode(new CaseLabel("CASEINFO")); case2.setProperty("name", "案件2"); case2.setProperty("address", "福田"); Node case3 = graphDB.createNode(new CaseLabel("CASEINFO")); case3.setProperty("name", "案件3"); case3.setProperty("address", "龙华"); Node userA = graphDB.createNode(new CaseLabel("PERSON")); userA.setProperty("name", "A"); userA.setProperty("idcard", "150302198012228239"); userA.setProperty("tel", "13685246639"); Node userB = graphDB.createNode(new CaseLabel("PERSON")); userB.setProperty("name", "B"); userB.setProperty("idcard", "370634199208304929"); userB.setProperty("tel", "13885246670"); Node userC = graphDB.createNode(new CaseLabel("PERSON")); userC.setProperty("name", "C"); userC.setProperty("idcard", "430721198802065735"); userC.setProperty("tel", "13966704782"); Node userD = graphDB.createNode(new CaseLabel("PERSON")); userD.setProperty("name", "D"); userD.setProperty("idcard", "522730198707118747"); userD.setProperty("tel", "13670478962"); Node userE = graphDB.createNode(new CaseLabel("PERSON")); userE.setProperty("name", "E"); userE.setProperty("idcard", "622926198609158032"); userE.setProperty("tel", "13047829667"); Node userF = graphDB.createNode(new CaseLabel("PERSON")); userF.setProperty("name", "F"); userF.setProperty("idcard", "500114197706138305"); userF.setProperty("tel", "13478296670"); Node userG = graphDB.createNode(new CaseLabel("PERSON")); userG.setProperty("name", "G"); userG.setProperty("idcard", "500114106138305152"); userG.setProperty("tel", "13476670156"); Node userH = graphDB.createNode(new CaseLabel("PERSON")); userH.setProperty("name", "H"); userH.setProperty("idcard", "500114197704751236"); userH.setProperty("tel", "13296156670"); case1.createRelationshipTo(userA, RelTypes.CRIME); case1.createRelationshipTo(userB, RelTypes.CRIME); case1.createRelationshipTo(userC, RelTypes.CRIME); case1.createRelationshipTo(userD, RelTypes.CRIME); case2.createRelationshipTo(userB, RelTypes.CRIME); case2.createRelationshipTo(userC, RelTypes.CRIME); case2.createRelationshipTo(userE, RelTypes.CRIME); // case2.createRelationshipTo(userD, RelTypes.CRIME); case3.createRelationshipTo(userF, RelTypes.CRIME); case3.createRelationshipTo(userG, RelTypes.CRIME); case3.createRelationshipTo(userH, RelTypes.CRIME); tx.success(); tx.close(); } public void search(String username) { Transaction tx = graphDB.beginTx(); Node startNode = graphDB.findNode(new CaseLabel("PERSON"), "name", username); Iterable<Relationship> iterable = startNode .getRelationships(RelTypes.CRIME, Direction.INCOMING); for (Relationship r : iterable) { Node node = r.getStartNode(); long id = node.getId(); String name = (String)node.getProperty("name"); // String idcard = (String)node.getProperty("idcard"); // String tel = (String)node.getProperty("tel"); System.out.println(id + " " + name+ " "); } tx.success(); tx.close(); } /**遍历查找**/ public void searchUser(String username) { Transaction tx = graphDB.beginTx(); Node startNode = graphDB.findNode(new CaseLabel("PERSON"), "name", username); // Node startNode = graphDB.findNode(new CaseLabel("PERSON"), "name", "B"); TraversalDescription td = graphDB.traversalDescription(); td.relationships(RelTypes.CRIME, Direction.OUTGOING);//沿着关系 TONG td.depthFirst();//设置深度优先 // td.evaluator(Evaluators.excludeStartPosition()); //从开始节点开始 Iterable<Node> it = td.traverse(startNode).nodes(); for (Node node : it) { long id = node.getId(); if( node.hasLabel( new CaseLabel("PERSON") )) { String name = (String)node.getProperty("name"); String idcard = (String)node.getProperty("idcard"); String tel = (String)node.getProperty("tel"); System.out.println(id + " " + name+ " " + idcard + " " + tel); } else { // String name = (String)node.getProperty("name"); // String address = (String)node.getProperty("address"); // System.out.println(id + " " + name+ " " + address); } } tx.success(); tx.close(); } /**查询所有案件信息*/ public void searchAllCase() { Transaction tx = graphDB.beginTx(); ResourceIterator<Node> iterator = graphDB.findNodes(new CaseLabel("CASEINFO")); for (ResourceIterator<Node> it = iterator; it.hasNext(); ) { Node node = it.next(); long id = node.getId(); String name = (String)node.getProperty("name"); String address = (String)node.getProperty("address"); System.out.println(id + " " + name+ " " + address); } tx.success(); tx.close(); } /**查询所有作案人员信息*/ public void searchAllPerson() { Transaction tx = graphDB.beginTx(); ResourceIterator<Node> iterator = graphDB.findNodes(new CaseLabel("PERSON")); for (ResourceIterator<Node> it = iterator; it.hasNext(); ) { Node node = it.next(); long id = node.getId(); String name = (String)node.getProperty("name"); String idcard = (String)node.getProperty("idcard"); String tel = (String)node.getProperty("tel"); System.out.println(id + " " + name+ " " + idcard + " " + tel); } tx.success(); tx.close(); } public static void main(String[] args) { CaseInfoAs as = new CaseInfoAs(); as.init(); // as.create(); as.search("A"); // as.search1(); // as.searchAllCase(); // as.searchUser("A"); } } class CaseLabel implements Label { private String name; public CaseLabel(String name) { this.name = name; } public String name(){ return name; } }

    生成的图

     

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