Java tutorial
/* 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.node.ObjectNode; import com.redhat.lightblue.util.Error; /** * Base class for primitive update expressions * <pre> * primitive_update_expression := { $set : { path : rvalue_expression , ...} } | * { $unset : path } | * { $unset :[ path, ... ] } * { $add : { path : rvalue_expression, ... } } * </pre> */ public abstract class PrimitiveUpdateExpression extends PartialUpdateExpression { private static final long serialVersionUID = 1L; /** * Parses a primitive expression using the given json object */ public static PrimitiveUpdateExpression fromJson(ObjectNode node) { if (node.has(UpdateOperator._add.toString()) || node.has(UpdateOperator._set.toString())) { return SetExpression.fromJson(node); } else if (node.has(UpdateOperator._unset.toString())) { return UnsetExpression.fromJson(node); } else { throw Error.get(QueryConstants.ERR_INVALID_UPDATE_EXPRESSION, node.toString()); } } }