/*
* 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
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* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
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* See the License for the specific language governing permissions and
* limitations under the License.
*
* Other licenses:
* -----------------------------------------------------------------------------
* Commercial licenses for this work are available. These replace the above
* ASL 2.0 and offer limited warranties, support, maintenance, and commercial
* database integrations.
*
* For more information, please visit: http://www.jooq.org/licenses
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package org.jooq.impl;
import static java.util.Arrays.asList;
import static org.jooq.Clause.CONDITION;
import static org.jooq.Clause.CONDITION_COMPARISON;
import static org.jooq.Comparator.EQUALS;
import static org.jooq.Comparator.GREATER;
import static org.jooq.Comparator.GREATER_OR_EQUAL;
import static org.jooq.Comparator.LESS;
import static org.jooq.Comparator.LESS_OR_EQUAL;
import static org.jooq.Comparator.NOT_EQUALS;
// ...
// ...
import static org.jooq.SQLDialect.CUBRID;
// ...
import static org.jooq.SQLDialect.DERBY;
import static org.jooq.SQLDialect.FIREBIRD;
// ...
// ...
// ...
// ...
// ...
import static org.jooq.SQLDialect.SQLITE;
// ...
// ...
import static org.jooq.impl.Keywords.K_NOT;
import java.util.ArrayList;
import java.util.List;
import org.jooq.Clause;
import org.jooq.Comparator;
import org.jooq.Condition;
import org.jooq.Configuration;
import org.jooq.Context;
import org.jooq.Field;
import org.jooq.QueryPartInternal;
import org.jooq.Row;
import org.jooq.SQLDialect;
/**
* @author Lukas Eder
*/
@SuppressWarnings({ "unchecked", "rawtypes" })
final class RowCondition extends AbstractCondition {
/**
* Generated UID
*/
private static final long serialVersionUID = -1806139685201770706L;
private static final Clause[] CLAUSES = { CONDITION, CONDITION_COMPARISON };
private final Row left;
private final Row right;
private final Comparator comparator;
RowCondition(Row left, Row right, Comparator comparator) {
this.left = left;
this.right = right;
this.comparator = comparator;
}
@Override
public final void accept(Context<?> ctx) {
ctx.visit(delegate(ctx.configuration()));
}
@Override
public final Clause[] clauses(Context<?> ctx) {
return null;
}
private final QueryPartInternal delegate(Configuration configuration) {
SQLDialect dialect = configuration.dialect();
// Regular comparison predicate emulation
if (asList(EQUALS, NOT_EQUALS).contains(comparator) &&
asList(DERBY, FIREBIRD, SQLITE).contains(dialect.family())) {
List<Condition> conditions = new ArrayList<Condition>();
Field<?>[] leftFields = left.fields();
Field<?>[] rightFields = right.fields();
for (int i = 0; i < leftFields.length; i++) {
conditions.add(leftFields[i].equal((Field) rightFields[i]));
}
Condition result = DSL.and(conditions);
if (comparator == NOT_EQUALS) {
result = result.not();
}
return (QueryPartInternal) result;
}
// Ordering comparison predicate emulation
else if (asList(GREATER, GREATER_OR_EQUAL, LESS, LESS_OR_EQUAL).contains(comparator) &&
asList(DERBY, CUBRID, FIREBIRD, SQLITE).contains(dialect.family())) {
// The order component of the comparator (stripping the equal component)
Comparator order
= (comparator == GREATER) ? GREATER
: (comparator == GREATER_OR_EQUAL) ? GREATER
: (comparator == LESS) ? LESS
: (comparator == LESS_OR_EQUAL) ? LESS
: null;
// [#2658] The factored order component of the comparator (enforcing the equal component)
Comparator factoredOrder
= (comparator == GREATER) ? GREATER_OR_EQUAL
: (comparator == GREATER_OR_EQUAL) ? GREATER_OR_EQUAL
: (comparator == LESS) ? LESS_OR_EQUAL
: (comparator == LESS_OR_EQUAL) ? LESS_OR_EQUAL
: null;
// Whether the comparator has an equal component
boolean equal
= (comparator == GREATER_OR_EQUAL)
||(comparator == LESS_OR_EQUAL);
// The following algorithm emulates the equivalency of these expressions:
// (A, B, C) > (X, Y, Z)
// (A > X) OR (A = X AND B > Y) OR (A = X AND B = Y AND C > Z)
List<Condition> outer = new ArrayList<Condition>();
Field<?>[] leftFields = left.fields();
Field<?>[] rightFields = right.fields();
for (int i = 0; i < leftFields.length; i++) {
List<Condition> inner = new ArrayList<Condition>();
for (int j = 0; j < i; j++) {
inner.add(leftFields[j].equal((Field) rightFields[j]));
}
inner.add(leftFields[i].compare(order, (Field) rightFields[i]));
outer.add(DSL.and(inner));
}
if (equal) {
outer.add(new RowCondition(left, right, Comparator.EQUALS));
}
Condition result = DSL.or(outer);
// [#2658] For performance reasons, an additional, redundant
// predicate is factored out to favour the application of range
// scans as the topmost predicate is AND-connected, not
// OR-connected:
// (A, B, C) > (X, Y, Z)
// (A >= X) AND ((A > X) OR (A = X AND B > Y) OR (A = X AND B = Y AND C > Z))
if (leftFields.length > 1) {
result = leftFields[0].compare(factoredOrder, (Field) rightFields[0]).and(result);
}
return (QueryPartInternal) result;
}
else {
return new Native();
}
}
private class Native extends AbstractCondition {
/**
* Generated UID
*/
private static final long serialVersionUID = -2977241780111574353L;
@Override
public final void accept(Context<?> ctx) {
// Some dialects do not support != comparison with rows
if (comparator == NOT_EQUALS && asList().contains(ctx.configuration().dialect().family())) {
ctx.visit(K_NOT).sql('(')
.visit(left).sql(" = ").visit(right)
.sql(')');
}
else {
// Some databases need extra parentheses around the RHS
boolean extraParentheses = asList().contains(ctx.configuration().dialect().family());
ctx.visit(left)
.sql(' ')
.sql(comparator.toSQL())
.sql(' ')
.sql(extraParentheses ? "(" : "")
.visit(right)
.sql(extraParentheses ? ")" : "");
}
}
@Override
public final Clause[] clauses(Context<?> ctx) {
return CLAUSES;
}
}
}