neo4j图形数据库第四弹——整合springboot（支持查询路径）

版权声明：博主原创，未经允许不得转载。 https://blog.csdn.net/qq_31748587/article/details/84308573

正经学徒，佛系记录，不搞事情

基于上文：https://blog.csdn.net/qq_31748587/article/details/84286411 的项目

普通的neo4j查询路径的cql语法如下：

match l=(m)-[]-(n) return l

neo4j还支持最短路径的查询方式，语法如下：

match l=shortestPath(({name:'Keanu Reeves'})-[*]-({title:"Jerry Maguire"})) return l

对应的springboot项目的工具类 Neo4jUtil 中添加方法 getPathList 对返回的路径进行解析

    /**
     * cql 路径查询 返回节点和关系
     * @param cql 查询语句
     * @param nodeList 节点
     * @param edgeList 关系
     * @return List<Map<String,Object>>
     */
    public static <T> void getPathList(String cql, Set<T> nodeList, Set<T> edgeList) {
        try {
            Session session = driver.session();
            StatementResult result = session.run(cql);
            List<Record> list = result.list();
            for (Record r : list) {
                for (String index : r.keys()) {
                    Path path = r.get(index).asPath();
                    //节点
                    Iterable<Node> nodes = path.nodes();
                    for (Iterator iter = nodes.iterator(); iter.hasNext(); ) {
                        InternalNode nodeInter = (InternalNode) iter.next();
                        Map<String, Object> map = new HashMap<>();
                        //节点上设置的属性
                        map.putAll(nodeInter.asMap());
                        //外加一个固定属性
                        map.put("nodeId", nodeInter.id());
                        nodeList.add((T) map);
                    }
                    //关系
                    Iterable<Relationship> edges = path.relationships();
                    for (Iterator iter = edges.iterator(); iter.hasNext(); ) {
                        InternalRelationship relationInter = (InternalRelationship) iter.next();
                        Map<String, Object> map = new HashMap<>();
                        map.putAll(relationInter.asMap());
                        //关系上设置的属性
                        map.put("edgeId", relationInter.id());
                        map.put("edgeFrom", relationInter.startNodeId());
                        map.put("edgeTo", relationInter.endNodeId());
                        edgeList.add((T) map);
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

 调用方法：

    @GetMapping("getPath")
    public Map<String, Object> getPath(){
        Map<String, Object> retMap = new HashMap<>();
        //cql语句
        String cql = "match l=(m)-[]-(n) return l";
        //待返回的值，与cql return后的值顺序对应
        Set<Map<String ,Object>> nodeList = new HashSet<>();
        Set<Map<String ,Object>> edgeList = new HashSet<>();
        neo4jUtil.getPathList(cql,nodeList,edgeList);
        retMap.put("nodeList",nodeList);
        retMap.put("edgeList",edgeList);
        return retMap;
    }
    @GetMapping("getShortPath")
    public Map<String, Object> getShortPath(){
        Map<String, Object> retMap = new HashMap<>();
        //cql语句
        String cql = "match l=shortestPath(({name:'Keanu Reeves'})-[*]-({title:\"Jerry Maguire\"})) return l";
        //待返回的值，与cql return后的值顺序对应
        Set<Map<String ,Object>> nodeList = new HashSet<>();
        Set<Map<String ,Object>> edgeList = new HashSet<>();
        neo4jUtil.getPathList(cql,nodeList,edgeList);
        retMap.put("nodeList",nodeList);
        retMap.put("edgeList",edgeList);
        return retMap;
    }

结果：

项目地址：

http://note.youdao.com/noteshare?id=9da90834156c95d23a6f80e3a28ba623