com.redhat.lightblue.query.ArrayAddExpression.java Source code

Introduction

Here is the source code for com.redhat.lightblue.query.ArrayAddExpression.java

Source

/*
 Copyright 2013 Red Hat, Inc. and/or its affiliates.
    
 This file is part of lightblue.
    
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU 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 General Public License for more details.
    
 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package com.redhat.lightblue.query;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.node.ArrayNode;
import com.fasterxml.jackson.databind.node.ObjectNode;
import com.redhat.lightblue.util.Error;
import com.redhat.lightblue.util.Path;

import java.util.*;

/**
 * Array append and insert operations
 * <pre>
 * array_update_expression := { $append : { path : rvalue_expression } } |
 *                            { $append : { path : [ rvalue_expression, ... ] }} |
 *                            { $insert : { path : rvalue_expression } } |
 *                            { $insert : { path : [ rvalue_expression,...] }}
 * </pre>
 */
public class ArrayAddExpression extends ArrayUpdateExpression {

    private static final long serialVersionUID = 1L;
    private final List<RValueExpression> values;
    private final UpdateOperator op;
    private final Path field;

    /**
     * Constructs an array update expression for insert and append operations
     */
    public ArrayAddExpression(Path field, UpdateOperator op, List<RValueExpression> list) {
        this.op = op;
        this.values = list;
        this.field = field;
    }

    /**
     * The array field to operate on
     */
    public Path getField() {
        return field;
    }

    /**
     * Values to be inserted or appended
     */
    public List<RValueExpression> getValues() {
        return values;
    }

    /**
     * The update operator
     */
    public UpdateOperator getOp() {
        return op;
    }

    @Override
    public JsonNode toJson() {
        ObjectNode node = getFactory().objectNode();
        ObjectNode args = getFactory().objectNode();
        if (values.size() == 1) {
            args.set(field.toString(), values.get(0).toJson());
        } else {
            ArrayNode arr = getFactory().arrayNode();
            for (RValueExpression v : values) {
                arr.add(v.toJson());
            }
            args.set(field.toString(), arr);
        }
        node.set(op.toString(), args);
        return node;
    }

    /**
     * Parses an array update expression using the given json object
     */
    public static ArrayAddExpression fromJson(ObjectNode node) {
        if (node.size() == 1) {
            UpdateOperator op = UpdateOperator._append;
            JsonNode arg = node.get(UpdateOperator._append.toString());
            if (arg == null) {
                arg = node.get(UpdateOperator._insert.toString());
                op = UpdateOperator._insert;
            }
            if (arg instanceof ObjectNode) {
                ObjectNode objArg = (ObjectNode) arg;
                if (objArg.size() == 1) {
                    Map.Entry<String, JsonNode> item = objArg.fields().next();
                    Path field = new Path(item.getKey());
                    JsonNode valueNode = item.getValue();
                    List<RValueExpression> rvalues = new ArrayList<>();
                    if (valueNode instanceof ArrayNode) {
                        for (Iterator<JsonNode> itr = ((ArrayNode) valueNode).elements(); itr.hasNext();) {
                            rvalues.add(RValueExpression.fromJson(itr.next()));
                        }
                    } else {
                        rvalues.add(RValueExpression.fromJson(valueNode));
                    }
                    return new ArrayAddExpression(field, op, rvalues);
                }
            }
        }
        throw Error.get(QueryConstants.ERR_INVALID_ARRAY_UPDATE_EXPRESSION, node.toString());
    }

    @Override
    public int hashCode() {
        int hash = 7;
        hash = 89 * hash + Objects.hashCode(this.values);
        hash = 89 * hash + Objects.hashCode(this.op);
        hash = 89 * hash + Objects.hashCode(this.field);
        return hash;
    }

    @Override
    public boolean equals(Object obj) {
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        final ArrayAddExpression other = (ArrayAddExpression) obj;
        if (!Objects.equals(this.values, other.values)) {
            return false;
        }
        if (this.op != other.op) {
            return false;
        }
        if (!Objects.equals(this.field, other.field)) {
            return false;
        }
        return true;
    }

}