neo4play.RelationshipService.java Source code

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Here is the source code for neo4play.RelationshipService.java

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// RelationshipService.java --- CRUD operations for relationships.

// Copyright (C) 2013-2015  Tim Krones

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published
// by the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.

// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package neo4play;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.node.ArrayNode;
import com.fasterxml.jackson.databind.node.JsonNodeFactory;
import com.fasterxml.jackson.databind.node.ObjectNode;
import models.nodes.LabeledNodeWithProperties;
import play.libs.F.Promise;
import play.libs.Json;
import play.libs.WS;

public class RelationshipService extends Neo4j {

    private static String buildMatchQuery(String startNodeLabel, JsonNode startNodeProps, String endNodeLabel,
            JsonNode endNodeProps) {
        return String.format("MATCH (s:%s), (e:%s) WHERE %s AND %s", startNodeLabel, endNodeLabel,
                buildConjunctiveConstraints("s", startNodeProps), buildConjunctiveConstraints("e", endNodeProps));
    }

    private static String buildMatchQuery(String startNodeLabel, JsonNode startNodeProps, String endNodeLabel,
            JsonNode endNodeProps, String type) {
        return String.format("MATCH (s:%s)-[r:%s]->(e:%s) WHERE %s AND %s", startNodeLabel, type, endNodeLabel,
                buildConjunctiveConstraints("s", startNodeProps), buildConjunctiveConstraints("e", endNodeProps));
    }

    private static String buildMatchQuery(String startNodeLabel, JsonNode startNodeProps, String endNodeLabel,
            JsonNode endNodeProps, String type, JsonNode relProps) {
        return String.format("MATCH (s:%s)-[r:%s]->(e:%s) WHERE %s AND %s AND %s", startNodeLabel, type,
                endNodeLabel, buildConjunctiveConstraints("s", startNodeProps),
                buildConjunctiveConstraints("e", endNodeProps), buildConjunctiveConstraints("r", relProps));
    }

    private static JsonNode buildStatements(String query) {
        ObjectNode statement = Json.newObject();
        statement.put("statement", query);
        ArrayNode statementList = JsonNodeFactory.instance.arrayNode();
        statementList.add(statement);
        ObjectNode statements = Json.newObject();
        statements.put("statements", statementList);
        return statements;
    }

    public static Promise<WS.Response> getRelationship(LabeledNodeWithProperties startNode,
            LabeledNodeWithProperties endNode, String type) {
        String query = buildMatchQuery(startNode.getLabel(), startNode.getProperties(), endNode.getLabel(),
                endNode.getProperties(), type) + " RETURN r";
        return postCypherQuery(query);
    }

    public static Promise<WS.Response> createRelationship(LabeledNodeWithProperties startNode,
            LabeledNodeWithProperties endNode, String type, String location) {
        String query = buildMatchQuery(startNode.getLabel(), startNode.getProperties(), endNode.getLabel(),
                endNode.getProperties()) + String.format(" CREATE (s)-[:%s]->(e)", type);
        JsonNode statements = buildStatements(query);
        return executeInTransaction(location, statements);
    }

    public static Promise<WS.Response> createRelationship(LabeledNodeWithProperties startNode,
            LabeledNodeWithProperties endNode, String type, JsonNode properties, String location) {
        String query = buildMatchQuery(startNode.getLabel(), startNode.getProperties(), endNode.getLabel(),
                endNode.getProperties()) + String.format(" CREATE (s)-[:%s {props}]->(e)", type);
        JsonNode statements = buildStatements(query, properties);
        return executeInTransaction(location, statements);
    }

    public static Promise<WS.Response> deleteRelationship(LabeledNodeWithProperties startNode,
            LabeledNodeWithProperties endNode, String type, String location) {
        String query = buildMatchQuery(startNode.getLabel(), startNode.getProperties(), endNode.getLabel(),
                endNode.getProperties(), type) + " DELETE r";
        JsonNode statements = buildStatements(query);
        return executeInTransaction(location, statements);
    }

    public static Promise<WS.Response> deleteRelationship(LabeledNodeWithProperties startNode,
            LabeledNodeWithProperties endNode, String type, JsonNode properties, String location) {
        String query = buildMatchQuery(startNode.getLabel(), startNode.getProperties(), endNode.getLabel(),
                endNode.getProperties(), type, properties) + " DELETE r";
        JsonNode statements = buildStatements(query);
        return executeInTransaction(location, statements);
    }

    public static Promise<WS.Response> deleteRelationships(LabeledNodeWithProperties startNode, String type,
            String location) {
        String query = String.format("MATCH (s:%s)-[r:%s]->() WHERE %s DELETE r", startNode.getLabel(), type,
                buildConjunctiveConstraints("s", startNode.getProperties()));
        JsonNode statements = buildStatements(query);
        return executeInTransaction(location, statements);
    }

    public static Promise<WS.Response> deleteRelationships(LabeledNodeWithProperties startNode, String type,
            JsonNode properties, String location) {
        String query = String.format("MATCH (s:%s)-[r:%s]->() WHERE %s AND %s DELETE r", startNode.getLabel(), type,
                buildConjunctiveConstraints("s", startNode.getProperties()),
                buildConjunctiveConstraints("r", properties));
        JsonNode statements = buildStatements(query);
        return executeInTransaction(location, statements);
    }

    public static Promise<WS.Response> to(LabeledNodeWithProperties endNode) {
        String query = String.format("MATCH ()-[r]->(e:%s) WHERE %s RETURN r", endNode.getLabel(),
                buildConjunctiveConstraints("e", endNode.getProperties()));
        return postCypherQuery(query);
    }

    public static Promise<WS.Response> to(LabeledNodeWithProperties endNode, String type) {
        String query = String.format("MATCH ()-[r:%s]->(e:%s) WHERE %s RETURN r", type, endNode.getLabel(),
                buildConjunctiveConstraints("e", endNode.getProperties()));
        return postCypherQuery(query);
    }

    public static Promise<WS.Response> endNodes(LabeledNodeWithProperties startNode, String type) {
        String query = String.format("MATCH (s:%s)-[:%s]->(e) WHERE %s RETURN e", startNode.getLabel(), type,
                buildConjunctiveConstraints("s", startNode.getProperties()));
        return postCypherQuery(query);
    }

    public static Promise<WS.Response> endNodes(LabeledNodeWithProperties startNode, String type,
            JsonNode properties) {
        String query = String.format("MATCH (s:%s)-[r:%s]->(e) WHERE %s AND %s RETURN e", startNode.getLabel(),
                type, buildConjunctiveConstraints("s", startNode.getProperties()),
                buildConjunctiveConstraints("r", properties));
        return postCypherQuery(query);
    }

    public static Promise<WS.Response> endNodes(LabeledNodeWithProperties startNode, String type, String location) {
        String query = String.format("MATCH (s:%s)-[:%s]->(e) WHERE %s RETURN e", startNode.getLabel(), type,
                buildConjunctiveConstraints("s", startNode.getProperties()));
        JsonNode statements = buildStatements(query);
        return executeInTransaction(location, statements);
    }

    public static Promise<WS.Response> endNodesByLabel(LabeledNodeWithProperties startNode, String type,
            String label) {
        String query = String.format("MATCH (s:%s)-[:%s]->(e:%s) WHERE %s RETURN e", startNode.getLabel(), type,
                label, buildConjunctiveConstraints("s", startNode.getProperties()));
        return postCypherQuery(query);

    }

    public static Promise<WS.Response> getRelationshipVariableLength(LabeledNodeWithProperties startNode,
            LabeledNodeWithProperties endNode, String type, int minHops, int maxHops) {
        String query = String.format("MATCH (s:%s)-[r:%s*%d..%d]->(e) WHERE %s AND %s RETURN r",
                startNode.getLabel(), type, minHops, maxHops,
                buildConjunctiveConstraints("s", startNode.getProperties()),
                buildConjunctiveConstraints("e", endNode.getProperties()));
        return postCypherQuery(query);
    }

    public static Promise<WS.Response> startNodes(String label, String type, LabeledNodeWithProperties endNode) {
        String query = String.format("MATCH (s:%s)-[:%s*]->(e:%s) WHERE %s RETURN s", label, type,
                endNode.getLabel(), buildConjunctiveConstraints("e", endNode.getProperties()));
        return postCypherQuery(query);
    }

}