Mercurial > hg > release > thermostat-0.11
view web/common/src/main/java/com/redhat/thermostat/web/common/ExpressionSerializer.java @ 1148:e597d72c3ecb
Add support for IN / NOT IN operators
This commit extends our query mechanism to handle queries of the form:
key IN [ x, y, z ], and key NOT IN [ x, y, z ]. I have added two new
Expression implementations, a BinarySetMembershipExpression and a
LiteralSetExpression. LiteralSetExpression corresponds to a list of
values, which can then be used as the right operand to a
BinarySetMembershipExpression. We have to explicitly pass the type of
value we're using in our list for deserialization.
I have also cleaned up the MongoExpressionParser in the process of
adding support for these new operators. UnaryLogicalExpressions now
can only take ComparisonExpressions, due to the restriction of how
$not is used in MongoDB.
Reviewed-by: vanaltj
Review-thread: http://icedtea.classpath.org/pipermail/thermostat/2013-June/007100.html
author | Elliott Baron <ebaron@redhat.com> |
---|---|
date | Fri, 28 Jun 2013 12:37:39 -0400 |
parents | bf720980510c |
children |
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/* * Copyright 2012, 2013 Red Hat, Inc. * * This file is part of Thermostat. * * Thermostat 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 2, or (at your * option) any later version. * * Thermostat 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 Thermostat; see the file COPYING. If not see * <http://www.gnu.org/licenses/>. * * Linking this code with other modules is making a combined work * based on this code. Thus, the terms and conditions of the GNU * General Public License cover the whole combination. * * As a special exception, the copyright holders of this code give * you permission to link this code with independent modules to * produce an executable, regardless of the license terms of these * independent modules, and to copy and distribute the resulting * executable under terms of your choice, provided that you also * meet, for each linked independent module, the terms and conditions * of the license of that module. An independent module is a module * which is not derived from or based on this code. If you modify * this code, you may extend this exception to your version of the * library, but you are not obligated to do so. If you do not wish * to do so, delete this exception statement from your version. */ package com.redhat.thermostat.web.common; import java.lang.reflect.Type; import java.util.HashSet; import java.util.Set; import com.google.gson.JsonArray; import com.google.gson.JsonDeserializationContext; import com.google.gson.JsonDeserializer; import com.google.gson.JsonElement; import com.google.gson.JsonObject; import com.google.gson.JsonParseException; import com.google.gson.JsonSerializationContext; import com.google.gson.JsonSerializer; import com.redhat.thermostat.storage.core.Key; import com.redhat.thermostat.storage.query.BinaryComparisonExpression; import com.redhat.thermostat.storage.query.BinaryComparisonOperator; import com.redhat.thermostat.storage.query.BinaryLogicalExpression; import com.redhat.thermostat.storage.query.BinaryLogicalOperator; import com.redhat.thermostat.storage.query.BinarySetMembershipExpression; import com.redhat.thermostat.storage.query.BinarySetMembershipOperator; import com.redhat.thermostat.storage.query.ComparisonExpression; import com.redhat.thermostat.storage.query.Expression; import com.redhat.thermostat.storage.query.LiteralExpression; import com.redhat.thermostat.storage.query.LiteralSetExpression; import com.redhat.thermostat.storage.query.Operator; import com.redhat.thermostat.storage.query.UnaryLogicalExpression; import com.redhat.thermostat.storage.query.UnaryLogicalOperator; public class ExpressionSerializer implements JsonSerializer<Expression>, JsonDeserializer<Expression> { /* The concrete Expression fully-qualified class name */ static final String PROP_CLASS_NAME = "PROP_CLASS_NAME"; /* Serialized operand for a UnaryExpression */ static final String PROP_OPERAND = "PROP_OPERAND"; /* Serialized left operand for a BinaryExpression */ static final String PROP_OPERAND_LEFT = "PROP_OPERAND_LEFT"; /* Serialized right operand for a BinaryExpression */ static final String PROP_OPERAND_RIGHT = "PROP_OPERAND_RIGHT"; /* Serialized operator for an Expression */ static final String PROP_OPERATOR = "PROP_OPERATOR"; /* Serialized value for a LiteralExpression */ static final String PROP_VALUE = "PROP_VALUE"; /* Fully-qualified class name of a LiteralExpression's value */ static final String PROP_VALUE_CLASS = "PROP_VALUE_CLASS"; @Override public Expression deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException { JsonElement jsonClassName = json.getAsJsonObject().get(PROP_CLASS_NAME); if (jsonClassName == null) { throw new JsonParseException("No class name property provided"); } String className = jsonClassName.getAsString(); Expression result; try { Class<?> clazz = (Class<?>) Class.forName(className); // Deserialize using concrete implementations to avoid reflection // and unchecked casts if (BinaryComparisonExpression.class.isAssignableFrom(clazz)) { result = deserializeBinaryComparisonExpression(json, context); } else if (BinarySetMembershipExpression.class.isAssignableFrom(clazz)) { result = deserializeBinarySetMembershipExpression(json, context); } else if (BinaryLogicalExpression.class.isAssignableFrom(clazz)) { result = deserializeBinaryLogicalExpression(json, context); } else if (UnaryLogicalExpression.class.isAssignableFrom(clazz)) { result = deserializeUnaryLogicalExpression(json, context); } else if (LiteralExpression.class.isAssignableFrom(clazz)) { result = deserializeLiteralExpression(json, context); } else if (LiteralSetExpression.class.isAssignableFrom(clazz)) { result = deserializeLiteralArrayExpression(json, context); } else { throw new JsonParseException("Unknown Expression of type " + className); } } catch (ClassNotFoundException e) { throw new JsonParseException("Unable to deserialize Expression", e); } return result; } private <T> Expression deserializeBinaryComparisonExpression(JsonElement json, JsonDeserializationContext context) { JsonElement jsonLeft = json.getAsJsonObject().get(PROP_OPERAND_LEFT); JsonElement jsonRight = json.getAsJsonObject().get(PROP_OPERAND_RIGHT); JsonElement jsonOp = json.getAsJsonObject().get(PROP_OPERATOR); LiteralExpression<Key<T>> left = context.deserialize(jsonLeft, Expression.class); LiteralExpression<T> right = context.deserialize(jsonRight, Expression.class); BinaryComparisonOperator op = context.deserialize(jsonOp, Operator.class); return new BinaryComparisonExpression<>(left, op, right); } private <T> Expression deserializeBinarySetMembershipExpression(JsonElement json, JsonDeserializationContext context) { JsonElement jsonLeft = json.getAsJsonObject().get(PROP_OPERAND_LEFT); JsonElement jsonRight = json.getAsJsonObject().get(PROP_OPERAND_RIGHT); JsonElement jsonOp = json.getAsJsonObject().get(PROP_OPERATOR); LiteralExpression<Key<T>> left = context.deserialize(jsonLeft, Expression.class); LiteralSetExpression<T> right = context.deserialize(jsonRight, Expression.class); BinarySetMembershipOperator op = context.deserialize(jsonOp, Operator.class); return new BinarySetMembershipExpression<>(left, op, right); } private <S extends Expression, T extends Expression> Expression deserializeBinaryLogicalExpression(JsonElement json, JsonDeserializationContext context) { JsonElement jsonLeft = json.getAsJsonObject().get(PROP_OPERAND_LEFT); JsonElement jsonRight = json.getAsJsonObject().get(PROP_OPERAND_RIGHT); JsonElement jsonOp = json.getAsJsonObject().get(PROP_OPERATOR); S left = context.deserialize(jsonLeft, Expression.class); T right = context.deserialize(jsonRight, Expression.class); BinaryLogicalOperator op = context.deserialize(jsonOp, Operator.class); return new BinaryLogicalExpression<>(left, op, right); } private <T extends ComparisonExpression> Expression deserializeUnaryLogicalExpression(JsonElement json, JsonDeserializationContext context) { JsonElement jsonOperand = json.getAsJsonObject().get(PROP_OPERAND); JsonElement jsonOp = json.getAsJsonObject().get(PROP_OPERATOR); T operand = context.deserialize(jsonOperand, Expression.class); UnaryLogicalOperator operator = context.deserialize(jsonOp, Operator.class); return new UnaryLogicalExpression<>(operand, operator); } private Expression deserializeLiteralExpression(JsonElement json, JsonDeserializationContext context) throws ClassNotFoundException { JsonElement jsonValue = json.getAsJsonObject().get(PROP_VALUE); JsonElement jsonValueClass = json.getAsJsonObject().get(PROP_VALUE_CLASS); String valueClassName = jsonValueClass.getAsString(); Class<?> valueClass = Class.forName(valueClassName); return makeLiteralExpression(context, jsonValue, valueClass); } private <T> Expression makeLiteralExpression(JsonDeserializationContext context, JsonElement jsonValue, Class<T> valueClass) throws ClassNotFoundException { T value = context.deserialize(jsonValue, valueClass); return new LiteralExpression<>(value); } private Expression deserializeLiteralArrayExpression(JsonElement json, JsonDeserializationContext context) throws ClassNotFoundException { JsonElement jsonValue = json.getAsJsonObject().get(PROP_VALUE); if (jsonValue instanceof JsonArray) { JsonElement jsonValueClass = json.getAsJsonObject().get(PROP_VALUE_CLASS); String valueClassName = jsonValueClass.getAsString(); Class<?> type = Class.forName(valueClassName); JsonArray jsonArr = (JsonArray) jsonValue; return makeLiteralArrayExpression(context, jsonArr, type); } else { throw new JsonParseException("No JsonArray supplied for " + PROP_VALUE); } } private <T> Expression makeLiteralArrayExpression(JsonDeserializationContext context, JsonArray jsonArr, Class<T> valueClass) { Set<T> values = new HashSet<>(); for (JsonElement element : jsonArr) { T value = context.deserialize(element, valueClass); values.add(value); } return new LiteralSetExpression<>(values, valueClass); } @Override public JsonElement serialize(Expression src, Type typeOfSrc, JsonSerializationContext context) { JsonObject result; // Only concrete implementations are public if (src instanceof BinaryLogicalExpression) { BinaryLogicalExpression<?, ?> binExpr = (BinaryLogicalExpression<?, ?>) src; JsonElement left = context.serialize(binExpr.getLeftOperand()); JsonElement op = context.serialize(binExpr.getOperator()); JsonElement right = context.serialize(binExpr.getRightOperand()); result = new JsonObject(); result.add(PROP_OPERAND_LEFT, left); result.add(PROP_OPERATOR, op); result.add(PROP_OPERAND_RIGHT, right); } else if (src instanceof BinaryComparisonExpression) { BinaryComparisonExpression<?> binExpr = (BinaryComparisonExpression<?>) src; JsonElement left = context.serialize(binExpr.getLeftOperand()); JsonElement op = context.serialize(binExpr.getOperator()); JsonElement right = context.serialize(binExpr.getRightOperand()); result = new JsonObject(); result.add(PROP_OPERAND_LEFT, left); result.add(PROP_OPERATOR, op); result.add(PROP_OPERAND_RIGHT, right); } else if (src instanceof BinarySetMembershipExpression) { BinarySetMembershipExpression<?> binExpr = (BinarySetMembershipExpression<?>) src; JsonElement left = context.serialize(binExpr.getLeftOperand()); JsonElement op = context.serialize(binExpr.getOperator()); JsonElement right = context.serialize(binExpr.getRightOperand()); result = new JsonObject(); result.add(PROP_OPERAND_LEFT, left); result.add(PROP_OPERATOR, op); result.add(PROP_OPERAND_RIGHT, right); } else if (src instanceof UnaryLogicalExpression) { UnaryLogicalExpression<?> unaryExpr = (UnaryLogicalExpression<?>) src; JsonElement operand = context.serialize(unaryExpr.getOperand()); JsonElement operator = context.serialize(unaryExpr.getOperator()); result = new JsonObject(); result.add(PROP_OPERAND, operand); result.add(PROP_OPERATOR, operator); } else if (src instanceof LiteralExpression) { LiteralExpression<?> litExpr = (LiteralExpression<?>) src; JsonElement value = context.serialize(litExpr.getValue()); result = new JsonObject(); result.add(PROP_VALUE, value); // Store the type of value to properly deserialize it later result.addProperty(PROP_VALUE_CLASS, litExpr.getValue().getClass().getCanonicalName()); } else if (src instanceof LiteralSetExpression) { LiteralSetExpression<?> litArrExpr = (LiteralSetExpression<?>) src; result = serializeLiteralArrayExpression(litArrExpr, context); } else { throw new JsonParseException("Unknown expression of type " + src.getClass()); } result.addProperty(PROP_CLASS_NAME, src.getClass().getCanonicalName()); return result; } private <T> JsonObject serializeLiteralArrayExpression(LiteralSetExpression<T> expr, JsonSerializationContext context) { JsonObject result = new JsonObject(); Set<T> list = expr.getValues(); Class<T> type = expr.getType(); JsonArray arr = new JsonArray(); for (T element : list) { arr.add(context.serialize(element, type)); } result.add(PROP_VALUE, arr); // Store type of list elements result.addProperty(PROP_VALUE_CLASS, type.getCanonicalName()); return result; } }