/**
* Copyright (C) 2012 the original author or authors.
*
* 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 co.jirm.orm.builder.select;
import static com.google.common.base.Strings.nullToEmpty;
import java.util.concurrent.atomic.AtomicBoolean;
import co.jirm.core.sql.MutableParameters;
import co.jirm.core.sql.Parameters;
import co.jirm.core.util.SafeAppendable;
import co.jirm.orm.builder.ConditionVisitors;
import co.jirm.orm.builder.ConditionVisitors.ParametersConditionVisitor;
public class SelectClauseVisitors {
public abstract static class SimpleClauseVisitor extends SelectClauseVisitor {
protected abstract void doVisit(SqlSelectClause<?> clause);
@Override
public abstract void visit(SelectWhereClauseBuilder<?> whereClauseBuilder);
@Override
public abstract void visit(OrderByClauseBuilder<?> clauseBuilder);
@Override
public void visit(LimitClauseBuilder<?> limitClauseBuilder) {
doVisit(limitClauseBuilder);
}
@Override
public void visit(OffsetClauseBuilder<?> clauseBuilder) {
doVisit(clauseBuilder);
}
@Override
public void visit(SelectCustomClauseBuilder<?> clauseBuilder) {
doVisit(clauseBuilder);
}
@Override
public void visit(ForUpdateClauseBuilder<?> clauseBuilder) {
doVisit(clauseBuilder);
}
@Override
public void visit(ForShareClauseBuilder<?> clauseBuilder) {
doVisit(clauseBuilder);
}
}
public abstract static class ParametersClauseVisitor extends SelectClauseVisitor {
private final ParametersConditionVisitor conditionVisitor = new ParametersConditionVisitor() {
@Override
public void doParameters(Parameters p) {
ParametersClauseVisitor.this.doParameters(p);
}
};
@Override
public void visit(SelectWhereClauseBuilder<?> whereClauseBuilder) {
whereClauseBuilder.getCondition().accept(conditionVisitor);
}
@Override
public void visit(LimitClauseBuilder<?> limitClauseBuilder) {
doParameters(limitClauseBuilder);
}
@Override
public void visit(OrderByClauseBuilder<?> clauseBuilder) {
doParameters(clauseBuilder);
}
@Override
public void visit(OffsetClauseBuilder<?> clauseBuilder) {
doParameters(clauseBuilder);
}
@Override
public void visit(SelectCustomClauseBuilder<?> clauseBuilder) {
doParameters(clauseBuilder);
}
@Override
public void visit(ForUpdateClauseBuilder<?> clauseBuilder) {
//NOOP
}
@Override
public void visit(ForShareClauseBuilder<?> clauseBuilder) {
//NOOP
}
public abstract void doParameters(Parameters p);
}
public static MutableParameters getParameters(SelectVisitorAcceptor k) {
final MutableParameters mp = new MutableParameters();
new ParametersClauseVisitor() {
@Override
public void doParameters(Parameters p) {
mp.addAll(p);
}
}.startOn(k);
return mp;
}
/*
* TODO move this to writer package.
*/
public static SelectClauseVisitor clauseVisitor(final Appendable appendable) {
final SafeAppendable sb = new SafeAppendable(appendable);
SimpleClauseVisitor cv = new SimpleClauseVisitor() {
AtomicBoolean first = new AtomicBoolean(true);
/*
* TODO take care of multiples and order.
*/
@Override
protected void doVisit(SqlSelectClause<?> clause) {
if (! appendStart(clause)) return;
sb.append(clause.getSql());
}
@Override
public void visit(SelectWhereClauseBuilder<?> whereClauseBuilder) {
if (! appendStart(whereClauseBuilder)) return;
whereClauseBuilder.getCondition().accept(ConditionVisitors.conditionVisitor(sb.getAppendable()));
}
@Override
public void visit(OrderByClauseBuilder<?> orderClauseBuilder) {
if ( ! appendStart(orderClauseBuilder) ) return;
if (nullToEmpty(orderClauseBuilder.getSql()).trim().isEmpty())
OrderByPartialVisitors.visitor(sb.getAppendable()).visit(orderClauseBuilder.getOrderByPartial());
else
sb.append(orderClauseBuilder.getSql());
}
private boolean appendStart(SelectClause<?> k) {
if (k.isNoOp()) return false;
if (first.get() ) {
first.set(false);
}
else {
sb.append(" ");
}
if (k.getType() != SelectClauseType.CUSTOM) {
sb.append(k.getType().getSql());
if (k.getType() != SelectClauseType.FORUPDATE &&
k.getType() != SelectClauseType.FORSHARE)
sb.append(" ");
}
return true;
}
};
return cv;
}
}