/*
*
* * Copyright 2014 Orient Technologies LTD (info(at)orientechnologies.com)
* *
* * Licensed under the Apache License, Version 2.0 (the "License");
* * you may not use this file except in compliance with the License.
* * You may obtain a copy of the License at
* *
* * http://www.apache.org/licenses/LICENSE-2.0
* *
* * Unless required by applicable law or agreed to in writing, software
* * distributed under the License is distributed on an "AS IS" BASIS,
* * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* * See the License for the specific language governing permissions and
* * limitations under the License.
* *
* * For more information: http://www.orientechnologies.com
*
*/
package com.orientechnologies.orient.core.sql.filter;
import com.orientechnologies.common.exception.OException;
import com.orientechnologies.common.parser.OBaseParser;
import com.orientechnologies.orient.core.command.OCommandContext;
import com.orientechnologies.orient.core.command.OCommandPredicate;
import com.orientechnologies.orient.core.db.record.OIdentifiable;
import com.orientechnologies.orient.core.exception.OQueryParsingException;
import com.orientechnologies.orient.core.metadata.schema.OProperty;
import com.orientechnologies.orient.core.record.impl.ODocument;
import com.orientechnologies.orient.core.serialization.serializer.OStringSerializerHelper;
import com.orientechnologies.orient.core.sql.OCommandExecutorSQLSelect;
import com.orientechnologies.orient.core.sql.OCommandSQLParsingException;
import com.orientechnologies.orient.core.sql.OSQLEngine;
import com.orientechnologies.orient.core.sql.OSQLHelper;
import com.orientechnologies.orient.core.sql.operator.OQueryOperator;
import com.orientechnologies.orient.core.sql.operator.OQueryOperatorNot;
import com.orientechnologies.orient.core.sql.query.OSQLSynchQuery;
import java.util.*;
/**
* Parses text in SQL format and build a tree of conditions.
*
* @author Luca Garulli
*
*/
public class OSQLPredicate extends OBaseParser implements OCommandPredicate {
protected Set<OProperty> properties = new HashSet<OProperty>();
protected OSQLFilterCondition rootCondition;
protected List<String> recordTransformed;
protected List<OSQLFilterItemParameter> parameterItems;
protected int braces;
protected OCommandContext context;
public OSQLPredicate() {
}
public OSQLPredicate(final String iText) {
text(iText);
}
protected void throwSyntaxErrorException(final String iText) {
final String syntax = getSyntax();
if (syntax.equals("?"))
throw new OCommandSQLParsingException(iText, parserText, parserGetPreviousPosition());
throw new OCommandSQLParsingException(iText + ". Use " + syntax, parserText, parserGetPreviousPosition());
}
protected String upperCase(String text) {
// TODO remove and refactor (see same method in OCommandExecutorAbstract)
StringBuilder result = new StringBuilder(text.length());
for (char c : text.toCharArray()) {
String upper = ("" + c).toUpperCase(Locale.ENGLISH);
if (upper.length() > 1) {
result.append(c);
} else {
result.append(upper);
}
}
return result.toString();
}
public OSQLPredicate text(final String iText) {
if (iText == null)
throw new OCommandSQLParsingException("Query text is null");
try {
parserText = iText;
parserTextUpperCase = upperCase(parserText);
parserSetCurrentPosition(0);
parserSkipWhiteSpaces();
rootCondition = (OSQLFilterCondition) extractConditions(null);
optimize();
} catch (OQueryParsingException e) {
if (e.getText() == null)
// QUERY EXCEPTION BUT WITHOUT TEXT: NEST IT
throw OException.wrapException(
new OQueryParsingException("Error on parsing query", parserText, parserGetCurrentPosition()), e);
throw e;
} catch (Exception t) {
throw OException.wrapException(new OQueryParsingException("Error on parsing query", parserText, parserGetCurrentPosition()),
t);
}
return this;
}
public Object evaluate() {
return evaluate(null, null, null);
}
public Object evaluate(final OCommandContext iContext) {
return evaluate(null, null, iContext);
}
public Object evaluate(final OIdentifiable iRecord, ODocument iCurrentResult, final OCommandContext iContext) {
if (rootCondition == null)
return true;
return rootCondition.evaluate(iRecord, iCurrentResult, iContext);
}
protected Object extractConditions(final OSQLFilterCondition iParentCondition) {
final int oldPosition = parserGetCurrentPosition();
parserNextWord(true, " )=><,\r\n", true);
final String word = parserGetLastWord();
boolean inBraces = word.length() > 0 && word.charAt(0) == OStringSerializerHelper.EMBEDDED_BEGIN;
if (word.length() > 0 && (word.equalsIgnoreCase("SELECT") || word.equalsIgnoreCase("TRAVERSE"))) {
// SUB QUERY
final StringBuilder embedded = new StringBuilder(256);
OStringSerializerHelper.getEmbedded(parserText, oldPosition - 1, -1, embedded);
parserSetCurrentPosition(oldPosition + embedded.length() + 1);
return new OSQLSynchQuery<Object>(embedded.toString());
}
parserSetCurrentPosition(oldPosition);
OSQLFilterCondition currentCondition = extractCondition();
// CHECK IF THERE IS ANOTHER CONDITION ON RIGHT
while (parserSkipWhiteSpaces()) {
if (!parserIsEnded() && parserGetCurrentChar() == ')')
return currentCondition;
final OQueryOperator nextOperator = extractConditionOperator();
if (nextOperator == null)
return currentCondition;
if (nextOperator.precedence > currentCondition.getOperator().precedence) {
// SWAP ITEMS
final OSQLFilterCondition subCondition = new OSQLFilterCondition(currentCondition.right, nextOperator);
currentCondition.right = subCondition;
subCondition.right = extractConditionItem(false, 1);
} else {
final OSQLFilterCondition parentCondition = new OSQLFilterCondition(currentCondition, nextOperator);
parentCondition.right = extractConditions(parentCondition);
currentCondition = parentCondition;
}
}
currentCondition.inBraces = inBraces;
// END OF TEXT
return currentCondition;
}
protected OSQLFilterCondition extractCondition() {
if (!parserSkipWhiteSpaces())
// END OF TEXT
return null;
// EXTRACT ITEMS
Object left = extractConditionItem(true, 1);
if (left != null && checkForEnd(left.toString()))
return null;
OQueryOperator oper;
final Object right;
if (left instanceof OQueryOperator && ((OQueryOperator) left).isUnary()) {
oper = (OQueryOperator) left;
left = extractConditionItem(false, 1);
right = null;
} else {
oper = extractConditionOperator();
if (oper instanceof OQueryOperatorNot)
// SPECIAL CASE: READ NEXT OPERATOR
oper = new OQueryOperatorNot(extractConditionOperator());
right = oper != null ? extractConditionItem(false, oper.expectedRightWords) : null;
}
// CREATE THE CONDITION OBJECT
return new OSQLFilterCondition(left, oper, right);
}
protected boolean checkForEnd(final String iWord) {
if (iWord != null
&& (iWord.equals(OCommandExecutorSQLSelect.KEYWORD_ORDER) || iWord.equals(OCommandExecutorSQLSelect.KEYWORD_LIMIT)
|| iWord.equals(OCommandExecutorSQLSelect.KEYWORD_SKIP) || iWord.equals(OCommandExecutorSQLSelect.KEYWORD_OFFSET))) {
parserMoveCurrentPosition(iWord.length() * -1);
return true;
}
return false;
}
private OQueryOperator extractConditionOperator() {
if (!parserSkipWhiteSpaces())
// END OF PARSING: JUST RETURN
return null;
if (parserGetCurrentChar() == ')')
// FOUND ')': JUST RETURN
return null;
final OQueryOperator[] operators = OSQLEngine.getInstance().getRecordOperators();
final String[] candidateOperators = new String[operators.length];
for (int i = 0; i < candidateOperators.length; ++i)
candidateOperators[i] = operators[i].keyword;
final int operatorPos = parserNextChars(true, false, candidateOperators);
if (operatorPos == -1) {
parserGoBack();
return null;
}
final OQueryOperator op = operators[operatorPos];
if (op.expectsParameters) {
// PARSE PARAMETERS IF ANY
parserGoBack();
parserNextWord(true, " 0123456789'\"");
final String word = parserGetLastWord();
final List<String> params = new ArrayList<String>();
// CHECK FOR PARAMETERS
if (word.length() > op.keyword.length() && word.charAt(op.keyword.length()) == OStringSerializerHelper.EMBEDDED_BEGIN) {
int paramBeginPos = parserGetCurrentPosition() - (word.length() - op.keyword.length());
parserSetCurrentPosition(OStringSerializerHelper.getParameters(parserText, paramBeginPos, -1, params));
} else if (!word.equals(op.keyword))
throw new OQueryParsingException("Malformed usage of operator '" + op.toString() + "'. Parsed operator is: " + word);
try {
// CONFIGURE COULD INSTANTIATE A NEW OBJECT: ACT AS A FACTORY
return op.configure(params);
} catch (Exception e) {
throw OException.wrapException(new OQueryParsingException("Syntax error using the operator '" + op.toString()
+ "'. Syntax is: " + op.getSyntax()), e);
}
} else
parserMoveCurrentPosition(+1);
return op;
}
private Object extractConditionItem(final boolean iAllowOperator, final int iExpectedWords) {
final Object[] result = new Object[iExpectedWords];
for (int i = 0; i < iExpectedWords; ++i) {
parserNextWord(false, " =><,\r\n", true);
String word = parserGetLastWord();
if (word.length() == 0)
break;
final String uWord = word.toUpperCase();
final int lastPosition = parserIsEnded() ? parserText.length() : parserGetCurrentPosition();
if (word.length() > 0 && word.charAt(0) == OStringSerializerHelper.EMBEDDED_BEGIN) {
braces++;
// SUB-CONDITION
parserSetCurrentPosition(lastPosition - word.length() + 1);
final Object subCondition = extractConditions(null);
if (!parserSkipWhiteSpaces() || parserGetCurrentChar() == ')') {
braces--;
parserMoveCurrentPosition(+1);
}
if (subCondition instanceof OSQLFilterCondition) {
((OSQLFilterCondition) subCondition).inBraces = true;
}
result[i] = subCondition;
} else if (word.charAt(0) == OStringSerializerHelper.LIST_BEGIN) {
// COLLECTION OF ELEMENTS
parserSetCurrentPosition(lastPosition - getLastWordLength());
final List<String> stringItems = new ArrayList<String>();
parserSetCurrentPosition(OStringSerializerHelper.getCollection(parserText, parserGetCurrentPosition(), stringItems));
result[i] = convertCollectionItems(stringItems);
parserMoveCurrentPosition(+1);
} else if (uWord.startsWith(OSQLFilterItemFieldAll.NAME + OStringSerializerHelper.EMBEDDED_BEGIN)) {
result[i] = new OSQLFilterItemFieldAll(this, word, null);
} else if (uWord.startsWith(OSQLFilterItemFieldAny.NAME + OStringSerializerHelper.EMBEDDED_BEGIN)) {
result[i] = new OSQLFilterItemFieldAny(this, word, null);
} else {
if (uWord.equals("NOT")) {
if (iAllowOperator)
return new OQueryOperatorNot();
else {
// GET THE NEXT VALUE
parserNextWord(false, " )=><,\r\n");
final String nextWord = parserGetLastWord();
if (nextWord.length() > 0) {
word += " " + nextWord;
if (word.endsWith(")"))
word = word.substring(0, word.length() - 1);
}
}
} else if (uWord.equals("AND"))
// SPECIAL CASE IN "BETWEEN X AND Y"
result[i] = word;
while (word.endsWith(")")) {
final int openParenthesis = word.indexOf('(');
if (openParenthesis == -1) {
// DISCARD END PARENTHESIS
word = word.substring(0, word.length() - 1);
parserMoveCurrentPosition(-1);
} else
break;
}
result[i] = OSQLHelper.parseValue(this, this, word, context);
}
}
return iExpectedWords == 1 ? result[0] : result;
}
private List<Object> convertCollectionItems(List<String> stringItems) {
List<Object> coll = new ArrayList<Object>();
for (String s : stringItems) {
coll.add(OSQLHelper.parseValue(this, this, s, context));
}
return coll;
}
public OSQLFilterCondition getRootCondition() {
return rootCondition;
}
@Override
public String toString() {
if (rootCondition != null)
return "Parsed: " + rootCondition.toString();
return "Unparsed: " + parserText;
}
/**
* Binds parameters.
*/
public void bindParameters(final Map<Object, Object> iArgs) {
if (parameterItems == null || iArgs == null || iArgs.size() == 0)
return;
for (int i = 0; i < parameterItems.size(); i++) {
OSQLFilterItemParameter value = parameterItems.get(i);
if ("?".equals(value.getName())) {
value.setValue(iArgs.get(i));
} else {
value.setValue(iArgs.get(value.getName()));
}
}
}
public OSQLFilterItemParameter addParameter(final String iName) {
final String name;
if (iName.charAt(0) == OStringSerializerHelper.PARAMETER_NAMED) {
name = iName.substring(1);
// CHECK THE PARAMETER NAME IS CORRECT
if (!OStringSerializerHelper.isAlphanumeric(name)) {
throw new OQueryParsingException("Parameter name '" + name + "' is invalid, only alphanumeric characters are allowed");
}
} else
name = iName;
final OSQLFilterItemParameter param = new OSQLFilterItemParameter(name);
if (parameterItems == null)
parameterItems = new ArrayList<OSQLFilterItemParameter>();
parameterItems.add(param);
return param;
}
public void setRootCondition(final OSQLFilterCondition iCondition) {
rootCondition = iCondition;
}
protected void optimize() {
if (rootCondition != null)
computePrefetchFieldList(rootCondition, new HashSet<String>());
}
protected Set<String> computePrefetchFieldList(final OSQLFilterCondition iCondition, final Set<String> iFields) {
Object left = iCondition.getLeft();
Object right = iCondition.getRight();
if (left instanceof OSQLFilterItemField) {
((OSQLFilterItemField) left).setPreLoadedFields(iFields);
iFields.add(((OSQLFilterItemField) left).getRoot());
} else if (left instanceof OSQLFilterCondition)
computePrefetchFieldList((OSQLFilterCondition) left, iFields);
if (right instanceof OSQLFilterItemField) {
((OSQLFilterItemField) right).setPreLoadedFields(iFields);
iFields.add(((OSQLFilterItemField) right).getRoot());
} else if (right instanceof OSQLFilterCondition)
computePrefetchFieldList((OSQLFilterCondition) right, iFields);
return iFields;
}
}