/*
* Copyright 2015, The Querydsl Team (http://www.querydsl.com/team)
*
* 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 com.querydsl.jpa;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import javax.persistence.Column;
import javax.persistence.Table;
import com.google.common.collect.ArrayListMultimap;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ListMultimap;
import com.google.common.collect.Lists;
import com.querydsl.core.JoinExpression;
import com.querydsl.core.QueryMetadata;
import com.querydsl.core.types.*;
import com.querydsl.sql.*;
/**
* {@code NativeSQLSerializer} extends {@link SQLSerializer} to extract referenced entity paths and change
* some serialization formats
*
* @author tiwe
*
*/
public final class NativeSQLSerializer extends SQLSerializer {
private final ListMultimap<Expression<?>, String> aliases = ArrayListMultimap.create();
private final boolean wrapEntityProjections;
public NativeSQLSerializer(Configuration configuration) {
this(configuration, false);
}
public NativeSQLSerializer(Configuration configuration, boolean wrapEntityProjections) {
super(configuration);
this.wrapEntityProjections = wrapEntityProjections;
}
@Override
protected void appendAsColumnName(Path<?> path, boolean precededByDot) {
if (path.getAnnotatedElement().isAnnotationPresent(Column.class)) {
Column column = path.getAnnotatedElement().getAnnotation(Column.class);
if (!column.name().isEmpty()) {
append(getTemplates().quoteIdentifier(column.name(), precededByDot));
} else {
super.appendAsColumnName(path, precededByDot);
}
} else {
super.appendAsColumnName(path, precededByDot);
}
}
@Override
protected void handleJoinTarget(JoinExpression je) {
SQLTemplates templates = getTemplates();
Class<?> type = je.getTarget().getType();
if (type.isAnnotationPresent(Table.class) && templates.isSupportsAlias()) {
Table table = type.getAnnotation(Table.class);
boolean precededByDot;
if (!table.schema().isEmpty() && templates.isPrintSchema()) {
appendSchemaName(table.schema());
append(".");
precededByDot = true;
} else {
precededByDot = false;
}
appendTableName(table.name(), precededByDot);
append(templates.getTableAlias());
}
super.handleJoinTarget(je);
}
private boolean isAlias(Expression<?> expr) {
return expr instanceof Operation && ((Operation<?>) expr).getOperator() == Ops.ALIAS;
}
public ListMultimap<Expression<?>, String> getAliases() {
return aliases;
}
private boolean isAllExpression(Expression<?> expr) {
if (expr instanceof Operation) {
return ((Operation<?>) expr).getOperator() == SQLOps.ALL;
} else if (expr instanceof TemplateExpression) {
return ((TemplateExpression<?>) expr).getTemplate().toString().equals("*");
} else {
return false;
}
}
@Override
public void serialize(QueryMetadata metadata, boolean forCountRow) {
// TODO get rid of this wrapping when Hibernate doesn't require unique aliases anymore
boolean modified = false;
Set<String> used = new HashSet<String>();
Expression<?> projection = metadata.getProjection();
if (projection instanceof Path) {
Path<?> path = (Path<?>) projection;
if (!used.add(path.getMetadata().getName())) {
String alias = "col_1";
aliases.put(projection, alias);
projection = ExpressionUtils.as(projection, alias);
modified = true;
} else if (path.getAnnotatedElement().isAnnotationPresent(Column.class)) {
Column column = path.getAnnotatedElement().getAnnotation(Column.class);
if (!column.name().isEmpty()) {
aliases.put(path, column.name());
} else {
aliases.put(path, ColumnMetadata.getName(path));
}
} else {
aliases.put(path, ColumnMetadata.getName(path));
}
} else if (projection instanceof FactoryExpression) {
FactoryExpression<?> factoryExpr = (FactoryExpression<?>) projection;
List<Expression<?>> fargs = Lists.newArrayList(factoryExpr.getArgs());
for (int j = 0; j < fargs.size(); j++) {
if (fargs.get(j) instanceof Path) {
Path<?> path = (Path<?>) fargs.get(j);
String columnName;
if (path.getAnnotatedElement().isAnnotationPresent(Column.class)) {
Column column = path.getAnnotatedElement().getAnnotation(Column.class);
if (!column.name().isEmpty()) {
columnName = column.name();
} else {
columnName = ColumnMetadata.getName(path);
}
} else {
columnName = ColumnMetadata.getName(path);
}
if (!used.add(columnName)) {
String alias = "col_" + (j + 1);
aliases.put(path, alias);
fargs.set(j, ExpressionUtils.as(fargs.get(j), alias));
} else {
aliases.put(path, columnName);
}
} else if (isAlias(fargs.get(j))) {
Operation<?> operation = (Operation<?>) fargs.get(j);
aliases.put(operation, operation.getArg(1).toString());
} else if (!isAllExpression(fargs.get(j))) {
String alias = "col_" + (j + 1);
aliases.put(fargs.get(j), alias);
fargs.set(j, ExpressionUtils.as(fargs.get(j), alias));
}
}
projection = Projections.tuple(ImmutableList.copyOf(fargs));
modified = true;
} else if (isAlias(projection)) {
Operation<?> operation = (Operation<?>) projection;
aliases.put(operation, operation.getArg(1).toString());
} else {
// https://github.com/querydsl/querydsl/issues/80
if (!isAllExpression(projection)) {
String alias = "col_1";
aliases.put(projection, alias);
projection = ExpressionUtils.as(projection, alias);
modified = true;
}
}
if (modified) {
metadata = metadata.clone();
metadata.setProjection(projection);
}
super.serialize(metadata, forCountRow);
}
@Override
public void visitConstant(Object constant) {
if (constant instanceof Collection<?>) {
append("(");
boolean first = true;
for (Object element : ((Collection<?>) constant)) {
if (!first) {
append(", ");
}
visitConstant(element);
first = false;
}
append(")");
} else if (!getConstantToLabel().containsKey(constant)) {
String constLabel = String.valueOf(getConstantToLabel().size() + 1);
getConstantToLabel().put(constant, constLabel);
append("?" + constLabel);
} else {
append("?" + getConstantToLabel().get(constant));
}
}
@Override
protected void visitOperation(Class<?> type, Operator operator, List<? extends Expression<?>> args) {
if (operator == SQLOps.ALL
&& !RelationalPath.class.isInstance(args.get(0))
&& wrapEntityProjections) {
append("{");
super.visitOperation(type, operator, args);
append("}");
} else {
super.visitOperation(type, operator, args);
}
}
}