/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.jackrabbit.oak.query.xpath;
import java.util.ArrayList;
import org.apache.jackrabbit.oak.query.QueryImpl;
import org.apache.jackrabbit.oak.query.xpath.Expression.OrCondition;
import org.apache.jackrabbit.oak.query.xpath.Expression.Property;
/**
* An xpath statement.
*/
public class Statement {
private String xpathQuery;
private boolean explain;
private boolean measure;
/**
* The selector to get the columns from (the selector used in the select
* column list).
*/
private Selector columnSelector;
private ArrayList<Expression> columnList = new ArrayList<Expression>();
/**
* All selectors.
*/
private ArrayList<Selector> selectors;
private Expression where;
private ArrayList<Order> orderList = new ArrayList<Order>();
public Statement optimize() {
if (explain || measure || orderList.size() > 0) {
return this;
}
if (where == null) {
return this;
}
if (where instanceof OrCondition) {
OrCondition or = (OrCondition) where;
Statement s1 = new Statement();
s1.columnSelector = columnSelector;
s1.selectors = selectors;
s1.columnList = columnList;
s1.where = or.left;
Statement s2 = new Statement();
s2.columnSelector = columnSelector;
s2.selectors = selectors;
s2.columnList = columnList;
s2.where = or.right;
s2.xpathQuery = xpathQuery;
return new UnionStatement(s1, s2);
}
return this;
}
@Override
public String toString() {
StringBuilder buff = new StringBuilder();
// explain | measure ...
if (explain) {
buff.append("explain ");
} else if (measure) {
buff.append("measure ");
}
// select ...
buff.append("select ");
buff.append(new Expression.Property(columnSelector, QueryImpl.JCR_PATH).toString());
if (selectors.size() > 1) {
buff.append(" as ").append('[').append(QueryImpl.JCR_PATH).append(']');
}
buff.append(", ");
buff.append(new Expression.Property(columnSelector, QueryImpl.JCR_SCORE).toString());
if (selectors.size() > 1) {
buff.append(" as ").append('[').append(QueryImpl.JCR_SCORE).append(']');
}
if (columnList.isEmpty()) {
buff.append(", ");
buff.append(new Expression.Property(columnSelector, "*").toString());
} else {
for (int i = 0; i < columnList.size(); i++) {
buff.append(", ");
Expression e = columnList.get(i);
String columnName = e.toString();
buff.append(columnName);
if (selectors.size() > 1) {
buff.append(" as [").append(e.getColumnAliasName()).append("]");
}
}
}
// from ...
buff.append(" from ");
for (int i = 0; i < selectors.size(); i++) {
Selector s = selectors.get(i);
if (i > 0) {
buff.append(" inner join ");
}
String nodeType = s.nodeType;
if (nodeType == null) {
nodeType = "nt:base";
}
buff.append('[' + nodeType + ']').append(" as ").append(s.name);
if (s.joinCondition != null) {
buff.append(" on ").append(s.joinCondition);
}
}
// where ...
if (where != null) {
buff.append(" where ").append(where.toString());
}
// order by ...
if (!orderList.isEmpty()) {
buff.append(" order by ");
for (int i = 0; i < orderList.size(); i++) {
if (i > 0) {
buff.append(", ");
}
buff.append(orderList.get(i));
}
}
// leave original xpath string as a comment
if (xpathQuery != null) {
buff.append(" /* xpath: ");
buff.append(xpathQuery);
buff.append(" */");
}
return buff.toString();
}
public void setExplain(boolean explain) {
this.explain = explain;
}
public void setMeasure(boolean measure) {
this.measure = measure;
}
public void addSelectColumn(Property p) {
columnList.add(p);
}
public void setSelectors(ArrayList<Selector> selectors) {
this.selectors = selectors;
}
public void setWhere(Expression where) {
this.where = where;
}
public void addOrderBy(Order order) {
this.orderList.add(order);
}
public void setColumnSelector(Selector columnSelector) {
this.columnSelector = columnSelector;
}
public void setOriginalQuery(String xpathQuery) {
this.xpathQuery = xpathQuery;
}
/**
* A union statement.
*/
static class UnionStatement extends Statement {
private final Statement s1, s2;
UnionStatement(Statement s1, Statement s2) {
this.s1 = s1;
this.s2 = s2;
}
@Override
public String toString() {
return s1 + " union " + s2;
}
}
}