neo4j java_使用java操作Neo4j数据库

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

org.neo4j

neo4j

3.3.5

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 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 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 iterator = graphDB.findNodes(new CaseLabel("CASEINFO"));

for (ResourceIterator 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 iterator = graphDB.findNodes(new CaseLabel("PERSON"));

for (ResourceIterator 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

1.jpg