/*
* Copyright (c) 2011-2015 EPFL DATA Laboratory
* Copyright (c) 2014-2015 The Squall Collaboration (see NOTICE)
*
* All rights reserved.
*
* 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.
*/
package ch.epfl.data.squall.api.sql.visitors.squall;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.Stack;
import net.sf.jsqlparser.expression.AllComparisonExpression;
import net.sf.jsqlparser.expression.AnyComparisonExpression;
import net.sf.jsqlparser.expression.BinaryExpression;
import net.sf.jsqlparser.expression.CaseExpression;
import net.sf.jsqlparser.expression.DateValue;
import net.sf.jsqlparser.expression.DoubleValue;
import net.sf.jsqlparser.expression.Expression;
import net.sf.jsqlparser.expression.ExpressionVisitor;
import net.sf.jsqlparser.expression.Function;
import net.sf.jsqlparser.expression.InverseExpression;
import net.sf.jsqlparser.expression.JdbcParameter;
import net.sf.jsqlparser.expression.LongValue;
import net.sf.jsqlparser.expression.NullValue;
import net.sf.jsqlparser.expression.Parenthesis;
import net.sf.jsqlparser.expression.StringValue;
import net.sf.jsqlparser.expression.TimeValue;
import net.sf.jsqlparser.expression.TimestampValue;
import net.sf.jsqlparser.expression.WhenClause;
import net.sf.jsqlparser.expression.operators.arithmetic.Addition;
import net.sf.jsqlparser.expression.operators.arithmetic.BitwiseAnd;
import net.sf.jsqlparser.expression.operators.arithmetic.BitwiseOr;
import net.sf.jsqlparser.expression.operators.arithmetic.BitwiseXor;
import net.sf.jsqlparser.expression.operators.arithmetic.Concat;
import net.sf.jsqlparser.expression.operators.arithmetic.Division;
import net.sf.jsqlparser.expression.operators.arithmetic.Multiplication;
import net.sf.jsqlparser.expression.operators.arithmetic.Subtraction;
import net.sf.jsqlparser.expression.operators.conditional.AndExpression;
import net.sf.jsqlparser.expression.operators.conditional.OrExpression;
import net.sf.jsqlparser.expression.operators.relational.Between;
import net.sf.jsqlparser.expression.operators.relational.EqualsTo;
import net.sf.jsqlparser.expression.operators.relational.ExistsExpression;
import net.sf.jsqlparser.expression.operators.relational.ExpressionList;
import net.sf.jsqlparser.expression.operators.relational.GreaterThan;
import net.sf.jsqlparser.expression.operators.relational.GreaterThanEquals;
import net.sf.jsqlparser.expression.operators.relational.InExpression;
import net.sf.jsqlparser.expression.operators.relational.IsNullExpression;
import net.sf.jsqlparser.expression.operators.relational.ItemsListVisitor;
import net.sf.jsqlparser.expression.operators.relational.LikeExpression;
import net.sf.jsqlparser.expression.operators.relational.Matches;
import net.sf.jsqlparser.expression.operators.relational.MinorThan;
import net.sf.jsqlparser.expression.operators.relational.MinorThanEquals;
import net.sf.jsqlparser.expression.operators.relational.NotEqualsTo;
import net.sf.jsqlparser.schema.Column;
import net.sf.jsqlparser.statement.select.SubSelect;
import ch.epfl.data.squall.api.sql.optimizers.index.IndexTranslator;
import ch.epfl.data.squall.api.sql.schema.Schema;
import ch.epfl.data.squall.api.sql.util.NotFromMyBranchException;
import ch.epfl.data.squall.api.sql.util.ParserUtil;
import ch.epfl.data.squall.api.sql.util.TableAliasName;
import ch.epfl.data.squall.components.Component;
import ch.epfl.data.squall.expressions.ColumnReference;
import ch.epfl.data.squall.expressions.IntegerYearFromDate;
import ch.epfl.data.squall.expressions.ValueExpression;
import ch.epfl.data.squall.expressions.ValueSpecification;
import ch.epfl.data.squall.types.DateType;
import ch.epfl.data.squall.types.DoubleType;
import ch.epfl.data.squall.types.LongType;
import ch.epfl.data.squall.types.StringType;
import ch.epfl.data.squall.types.Type;
/*
* Returns a list of hashExpressions for a given component in a given query plan.
* If we do not have complexCondition,
* outside this class hashIndexes are extracted from hashExpressions.
*
* For example, on join condition R.B = S.B, from component R,
* we need to find the index of B. This is not so easy if
* a) R is not a DataSourceComponent)
* b) many operators down the path
*/
public class IndexJoinHashVisitor implements ExpressionVisitor,
ItemsListVisitor {
// these are only used within visit(Column) method
private Schema _schema;
private Component _affectedComponent;
private TableAliasName _tan;
private IndexTranslator _it;
// this will not break any contracts,
// even with new DateConversion() on all the places,
// we will have a single object per (possibly) multiple spout/bolt threads.
// generating plans is done from a single thread, static additionally saves
// space
private static LongType _lc = new LongType();
private static DoubleType _dblConv = new DoubleType();
private static DateType _dateConv = new DateType();
private static StringType _sc = new StringType();
private Stack<ValueExpression> _exprStack = new Stack<ValueExpression>();
private final List<ValueExpression> _hashExpressions = new ArrayList<ValueExpression>();
protected IndexJoinHashVisitor() {
}
/*
* affectedComponent is one of the parents of the join component
*/
public IndexJoinHashVisitor(Schema schema, Component affectedComponent,
TableAliasName tan) {
_schema = schema;
_affectedComponent = affectedComponent;
_tan = tan;
_it = new IndexTranslator(_schema, _tan);
}
public List<ValueExpression> getExpressions() {
return _hashExpressions;
}
protected void pushToExprStack(ValueExpression ve) {
_exprStack.push(ve);
}
/*
* Each of these operations create a Squall type, that's why so much similar
* code
*/
@Override
public void visit(Addition adtn) {
visitBinaryOperation(adtn);
final ValueExpression right = _exprStack.pop();
final ValueExpression left = _exprStack.pop();
final ValueExpression add = new ch.epfl.data.squall.expressions.Addition(
left, right);
_exprStack.push(add);
}
@Override
public void visit(AllComparisonExpression ace) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(AndExpression ae) {
visitBinaryOperation(ae);
}
@Override
public void visit(AnyComparisonExpression ace) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(Between btwn) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(BitwiseAnd ba) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(BitwiseOr bo) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(BitwiseXor bx) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(CaseExpression ce) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(Column column) {
final String tableCompName = ParserUtil.getComponentName(column);
final List<String> ancestorNames = ParserUtil
.getSourceNameList(_affectedComponent);
if (ancestorNames.contains(tableCompName)) {
// extract type for the column
final Type tc = _schema.getType(ParserUtil.getFullSchemaColumnName(
column, _tan));
// extract the position (index) of the required column
final int position = _it.getColumnIndex(column, _affectedComponent);
final ValueExpression ve = new ColumnReference(tc, position);
_exprStack.push(ve);
} else
throw new NotFromMyBranchException();
}
@Override
public void visit(Concat concat) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(DateValue dv) {
final ValueExpression ve = new ValueSpecification(_dateConv,
dv.getValue());
_exprStack.push(ve);
}
@Override
public void visit(Division dvsn) {
visitBinaryOperation(dvsn);
final ValueExpression right = _exprStack.pop();
final ValueExpression left = _exprStack.pop();
final ValueExpression division = new ch.epfl.data.squall.expressions.Division(
left, right);
_exprStack.push(division);
}
// all of ValueSpecifications (constants) guarantee we have some expressions
// in join conditions
@Override
public void visit(DoubleValue dv) {
final ValueExpression ve = new ValueSpecification(_dblConv,
dv.getValue());
_exprStack.push(ve);
}
@Override
public void visit(EqualsTo et) {
visitSideEquals(et.getLeftExpression());
visitSideEquals(et.getRightExpression());
}
@Override
public void visit(ExistsExpression ee) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(ExpressionList el) {
for (final Iterator iter = el.getExpressions().iterator(); iter
.hasNext();) {
final Expression expression = (Expression) iter.next();
expression.accept(this);
}
}
@Override
public void visit(Function function) {
// all aggregate functions (SUM, AVG, COUNT, MAX, MIN) have only one
// parameter (Expression)
// although COUNT(*) has no parameters
// EXTRACT_YEAR has one parameter
final ExpressionList params = function.getParameters();
int numParams = 0;
if (params != null) {
visit(params);
// only for size
final List<Expression> listParams = params.getExpressions();
numParams = listParams.size();
}
final List<ValueExpression> expressions = new ArrayList<ValueExpression>();
for (int i = 0; i < numParams; i++)
expressions.add(_exprStack.pop());
Collections.reverse(expressions); // at the stack top is the lastly
// added VE
final String fnName = function.getName();
if (fnName.equalsIgnoreCase("EXTRACT_YEAR")) {
if (numParams != 1)
throw new RuntimeException(
"EXTRACT_YEAR function has exactly one parameter!");
final ValueExpression expr = expressions.get(0);
final ValueExpression ve = new IntegerYearFromDate(expr);
_exprStack.push(ve);
}
}
@Override
public void visit(GreaterThan gt) {
visitUnsupportedOp();
}
@Override
public void visit(GreaterThanEquals gte) {
visitUnsupportedOp();
}
@Override
public void visit(InExpression ie) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(InverseExpression ie) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(IsNullExpression ine) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(JdbcParameter jp) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(LikeExpression le) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(LongValue lv) {
final ValueExpression ve = new ValueSpecification(_lc, lv.getValue());
_exprStack.push(ve);
}
@Override
public void visit(Matches mtchs) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(MinorThan mt) {
visitUnsupportedOp();
}
@Override
public void visit(MinorThanEquals mte) {
visitUnsupportedOp();
}
@Override
public void visit(Multiplication m) {
visitBinaryOperation(m);
final ValueExpression right = _exprStack.pop();
final ValueExpression left = _exprStack.pop();
final ValueExpression mult = new ch.epfl.data.squall.expressions.Multiplication(
left, right);
_exprStack.push(mult);
}
@Override
public void visit(NotEqualsTo net) {
visitUnsupportedOp();
}
// VISITOR DESIGN PATTERN
@Override
public void visit(NullValue nv) {
throw new UnsupportedOperationException("Not supported yet.");
}
// UNSUPPORTED
@Override
public void visit(OrExpression oe) {
throw new RuntimeException("OR in join condition is not yet supported!");
}
@Override
public void visit(Parenthesis prnths) {
prnths.getExpression().accept(this);
}
@Override
public void visit(StringValue sv) {
final ValueExpression ve = new ValueSpecification(_sc, sv.getValue());
_exprStack.push(ve);
}
@Override
public void visit(SubSelect ss) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(Subtraction s) {
visitBinaryOperation(s);
final ValueExpression right = _exprStack.pop();
final ValueExpression left = _exprStack.pop();
final ValueExpression sub = new ch.epfl.data.squall.expressions.Subtraction(
left, right);
_exprStack.push(sub);
}
@Override
public void visit(TimestampValue tv) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(TimeValue tv) {
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public void visit(WhenClause wc) {
throw new UnsupportedOperationException("Not supported yet.");
}
private void visitBinaryOperation(BinaryExpression be) {
be.getLeftExpression().accept(this);
be.getRightExpression().accept(this);
}
private void visitSideEquals(Expression ex) {
try {
_exprStack = new Stack<ValueExpression>();
ex.accept(this);
final ValueExpression ve = _exprStack.pop();
_hashExpressions.add(ve);
} catch (final NotFromMyBranchException exc) {
// expression would not be added in the list
}
}
private void visitUnsupportedOp() {
throw new RuntimeException(
"Only EQUALS operator can appear in join condition!");
}
}