package org.h2.expression.condition;
import org.h2.engine.Session;
import org.h2.expression.Expression;
import org.h2.expression.ExpressionVisitor;
import org.h2.expression.ValueExpression;
import org.h2.message.DbException;
import org.h2.table.ColumnResolver;
import org.h2.table.TableFilter;
import org.h2.value.Value;
import org.h2.value.ValueBoolean;
import org.h2.value.ValueNull;
public class ConditionAndOr extends Condition {
public static final int AND = 0;
public static final int OR = 1;
private final int andOrType;
private Expression left, right;
public ConditionAndOr(int andOrType, Expression left, Expression right) {
this.andOrType = andOrType;
this.left = left;
this.right = right;
if (left == null || right == null) {
DbException.throwInternalError(left + " " + right);
}
}
@Override
public StringBuilder getSQL(StringBuilder builder, boolean alwaysQuote) {
builder.append('(');
left.getSQL(builder, alwaysQuote);
switch (andOrType) {
case AND:
builder.append("\n AND ");
break;
case OR:
builder.append("\n OR ");
break;
default:
throw DbException.throwInternalError("andOrType=" + andOrType);
}
return right.getSQL(builder, alwaysQuote).append(')');
}
@Override
public void createIndexConditions(Session session, TableFilter filter) {
if (andOrType == AND) {
left.createIndexConditions(session, filter);
right.createIndexConditions(session, filter);
}
}
@Override
public Expression getNotIfPossible(Session session) {
Expression l = left.getNotIfPossible(session);
if (l == null) {
l = new ConditionNot(left);
}
Expression r = right.getNotIfPossible(session);
if (r == null) {
r = new ConditionNot(right);
}
int reversed = andOrType == AND ? OR : AND;
return new ConditionAndOr(reversed, l, r);
}
@Override
public Value getValue(Session session) {
Value l = left.getValue(session);
Value r;
switch (andOrType) {
case AND: {
if (l != ValueNull.INSTANCE && !l.getBoolean()) {
return l;
}
r = right.getValue(session);
if (r != ValueNull.INSTANCE && !r.getBoolean()) {
return r;
}
if (l == ValueNull.INSTANCE) {
return l;
}
if (r == ValueNull.INSTANCE) {
return r;
}
return ValueBoolean.TRUE;
}
case OR: {
if (l.getBoolean()) {
return l;
}
r = right.getValue(session);
if (r.getBoolean()) {
return r;
}
if (l == ValueNull.INSTANCE) {
return l;
}
if (r == ValueNull.INSTANCE) {
return r;
}
return ValueBoolean.FALSE;
}
default:
throw DbException.throwInternalError("type=" + andOrType);
}
}
@Override
public Expression optimize(Session session) {
left = left.optimize(session);
right = right.optimize(session);
int lc = left.getCost(), rc = right.getCost();
if (rc < lc) {
Expression t = left;
left = right;
right = t;
}
if (session.getDatabase().getSettings().optimizeTwoEquals &&
andOrType == AND) {
if (left instanceof Comparison && right instanceof Comparison) {
Comparison compLeft = (Comparison) left;
Comparison compRight = (Comparison) right;
Expression added = compLeft.getAdditional(
session, compRight, true);
if (added != null) {
added = added.optimize(session);
return new ConditionAndOr(AND, this, added);
}
}
}
if (andOrType == OR &&
session.getDatabase().getSettings().optimizeOr) {
if (left instanceof Comparison &&
right instanceof Comparison) {
Comparison compLeft = (Comparison) left;
Comparison compRight = (Comparison) right;
Expression added = compLeft.getAdditional(
session, compRight, false);
if (added != null) {
return added.optimize(session);
}
} else if (left instanceof ConditionIn &&
right instanceof Comparison) {
Expression added = ((ConditionIn) left).
getAdditional((Comparison) right);
if (added != null) {
return added.optimize(session);
}
} else if (right instanceof ConditionIn &&
left instanceof Comparison) {
Expression added = ((ConditionIn) right).
getAdditional((Comparison) left);
if (added != null) {
return added.optimize(session);
}
} else if (left instanceof ConditionInConstantSet &&
right instanceof Comparison) {
Expression added = ((ConditionInConstantSet) left).
getAdditional(session, (Comparison) right);
if (added != null) {
return added.optimize(session);
}
} else if (right instanceof ConditionInConstantSet &&
left instanceof Comparison) {
Expression added = ((ConditionInConstantSet) right).
getAdditional(session, (Comparison) left);
if (added != null) {
return added.optimize(session);
}
} else if (left instanceof ConditionAndOr &&
right instanceof ConditionAndOr ){
ConditionAndOr condAORight = (ConditionAndOr)right;
ConditionAndOr condAORLeft = (ConditionAndOr)left;
Expression reduced = optimizeConditionAndOr(condAORLeft,condAORight);
if(reduced != null){
return reduced.optimize(session);
}
}
}
Value l = left.isConstant() ? left.getValue(session) : null;
Value r = right.isConstant() ? right.getValue(session) : null;
if (l == null && r == null) {
return this;
}
if (l != null && r != null) {
return ValueExpression.get(getValue(session));
}
switch (andOrType) {
case AND:
if (l != null) {
if (l != ValueNull.INSTANCE && !l.getBoolean()) {
return ValueExpression.get(l);
} else if (l.getBoolean()) {
return right;
}
} else if (r != null) {
if (r != ValueNull.INSTANCE && !r.getBoolean()) {
return ValueExpression.get(r);
} else if (r.getBoolean()) {
return left;
}
}
break;
case OR:
if (l != null) {
if (l.getBoolean()) {
return ValueExpression.get(l);
} else if (l != ValueNull.INSTANCE) {
return right;
}
} else if (r != null) {
if (r.getBoolean()) {
return ValueExpression.get(r);
} else if (r != ValueNull.INSTANCE) {
return left;
}
}
break;
default:
DbException.throwInternalError("type=" + andOrType);
}
return this;
}
@Override
public void addFilterConditions(TableFilter filter, boolean outerJoin) {
if (andOrType == AND) {
left.addFilterConditions(filter, outerJoin);
right.addFilterConditions(filter, outerJoin);
} else {
super.addFilterConditions(filter, outerJoin);
}
}
@Override
public void mapColumns(ColumnResolver resolver, int level, int state) {
left.mapColumns(resolver, level, state);
right.mapColumns(resolver, level, state);
}
@Override
public void setEvaluatable(TableFilter tableFilter, boolean b) {
left.setEvaluatable(tableFilter, b);
right.setEvaluatable(tableFilter, b);
}
@Override
public void updateAggregate(Session session, int stage) {
left.updateAggregate(session, stage);
right.updateAggregate(session, stage);
}
@Override
public boolean isEverything(ExpressionVisitor visitor) {
return left.isEverything(visitor) && right.isEverything(visitor);
}
@Override
public int getCost() {
return left.getCost() + right.getCost();
}
@Override
public int getSubexpressionCount() {
return 2;
}
@Override
public Expression getSubexpression(int index) {
switch (index) {
case 0:
return left;
case 1:
return right;
default:
throw new IndexOutOfBoundsException();
}
}
private static Expression optimizeConditionAndOr(ConditionAndOr left, ConditionAndOr right) {
if (left.andOrType != AND || right.andOrType != AND) {
return null;
}
Expression leftLeft = left.getSubexpression(0), leftRight = left.getSubexpression(1);
Expression rightLeft = right.getSubexpression(0), rightRight = right.getSubexpression(1);
String leftLeftSQL = leftLeft.getSQL(true), rightLeftSQL = rightLeft.getSQL(true);
Expression combinedExpression;
if (leftLeftSQL.equals(rightLeftSQL)) {
combinedExpression = new ConditionAndOr(OR, leftRight, rightRight);
return new ConditionAndOr(AND, leftLeft, combinedExpression);
}
String rightRightSQL = rightRight.getSQL(true);
if (leftLeftSQL.equals(rightRightSQL)) {
combinedExpression = new ConditionAndOr(OR, leftRight, rightLeft);
return new ConditionAndOr(AND, leftLeft, combinedExpression);
}
String leftRightSQL = leftRight.getSQL(true);
if (leftRightSQL.equals(rightLeftSQL)) {
combinedExpression = new ConditionAndOr(OR, leftLeft, rightRight);
return new ConditionAndOr(AND, leftRight, combinedExpression);
} else if (leftRightSQL.equals(rightRightSQL)) {
combinedExpression = new ConditionAndOr(OR, leftLeft, rightLeft);
return new ConditionAndOr(AND, leftRight, combinedExpression);
}
return null;
}
}