org.apache.jackrabbit.spi.commons.query.sql.JCRSQLQueryBuilder Maven / Gradle / Ivy
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/*
* 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.spi.commons.query.sql;
import org.apache.jackrabbit.spi.commons.query.AndQueryNode;
import org.apache.jackrabbit.spi.commons.query.LocationStepQueryNode;
import org.apache.jackrabbit.spi.commons.query.NAryQueryNode;
import org.apache.jackrabbit.spi.commons.query.NodeTypeQueryNode;
import org.apache.jackrabbit.spi.commons.query.NotQueryNode;
import org.apache.jackrabbit.spi.commons.query.OrQueryNode;
import org.apache.jackrabbit.spi.commons.query.OrderQueryNode;
import org.apache.jackrabbit.spi.commons.query.PathQueryNode;
import org.apache.jackrabbit.spi.commons.query.QueryConstants;
import org.apache.jackrabbit.spi.commons.query.QueryNode;
import org.apache.jackrabbit.spi.commons.query.QueryRootNode;
import org.apache.jackrabbit.spi.commons.query.RelationQueryNode;
import org.apache.jackrabbit.spi.commons.query.TextsearchQueryNode;
import org.apache.jackrabbit.spi.commons.query.PropertyFunctionQueryNode;
import org.apache.jackrabbit.spi.commons.query.QueryNodeFactory;
import org.apache.jackrabbit.spi.commons.conversion.NameException;
import org.apache.jackrabbit.spi.commons.name.NameConstants;
import org.apache.jackrabbit.spi.commons.name.NameFactoryImpl;
import org.apache.jackrabbit.spi.commons.name.PathBuilder;
import org.apache.jackrabbit.spi.Name;
import org.apache.jackrabbit.spi.Path;
import org.apache.jackrabbit.spi.commons.conversion.MalformedPathException;
import org.apache.jackrabbit.spi.commons.conversion.NameResolver;
import org.apache.jackrabbit.util.ISO8601;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.commons.collections4.map.AbstractReferenceMap.ReferenceStrength;
import org.apache.commons.collections4.map.ReferenceMap;
import javax.jcr.query.InvalidQueryException;
import javax.jcr.NamespaceException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Calendar;
import java.util.Collection;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.NoSuchElementException;
import java.util.Map;
import java.io.StringReader;
/**
* Implements the query builder for the JCR SQL syntax.
*/
public class JCRSQLQueryBuilder implements JCRSQLParserVisitor {
/**
* logger instance for this class
*/
private static final Logger log = LoggerFactory.getLogger(JCRSQLQueryBuilder.class);
/**
* DateFormat pattern for type
* {@link org.apache.jackrabbit.spi.commons.query.QueryConstants#TYPE_DATE}.
*/
private static final String DATE_PATTERN = "yyyy-MM-dd";
/**
* Map of reusable JCRSQL parser instances indexed by NamespaceResolver.
*/
private static Map parsers = new ReferenceMap<>(ReferenceStrength.WEAK, ReferenceStrength.WEAK);
/**
* The root node of the sql query syntax tree
*/
private final ASTQuery stmt;
/**
* The root query node
*/
private QueryRootNode root;
/**
* To resolve QNames
*/
private NameResolver resolver;
/**
* Query node to gather the constraints defined in the WHERE clause
*/
private final AndQueryNode constraintNode;
/**
* The Name of the node type in the from clause.
*/
private Name nodeTypeName;
/**
* List of PathQueryNode constraints that need to be merged
*/
private final List pathConstraints = new ArrayList();
/**
* The query node factory.
*/
private final QueryNodeFactory factory;
/**
* Creates a new JCRSQLQueryBuilder.
*
* @param statement the root node of the SQL syntax tree.
* @param resolver a namespace resolver to use for names in the
* statement.
* @param factory the query node factory.
*/
private JCRSQLQueryBuilder(ASTQuery statement,
NameResolver resolver,
QueryNodeFactory factory) {
this.stmt = statement;
this.resolver = resolver;
this.factory = factory;
this.constraintNode = factory.createAndQueryNode(null);
}
/**
* Creates a QueryNode tree from a SQL statement
* using the passed query node factory.
*
* @param statement the SQL statement.
* @param resolver the namespace resolver to use.
* @return the QueryNode tree.
* @throws InvalidQueryException if statement is malformed.
*/
public static QueryRootNode createQuery(String statement,
NameResolver resolver,
QueryNodeFactory factory)
throws InvalidQueryException {
try {
// get parser
JCRSQLParser parser;
synchronized (parsers) {
parser = parsers.get(resolver);
if (parser == null) {
parser = new JCRSQLParser(new StringReader(statement));
parser.setNameResolver(resolver);
parsers.put(resolver, parser);
}
}
JCRSQLQueryBuilder builder;
// guard against concurrent use within same session
synchronized (parser) {
parser.ReInit(new StringReader(statement));
builder = new JCRSQLQueryBuilder(parser.Query(), resolver, factory);
}
return builder.getRootNode();
} catch (ParseException e) {
throw new InvalidQueryException(e.getMessage());
} catch (IllegalArgumentException e) {
throw new InvalidQueryException(e.getMessage());
} catch (Throwable t) {
// javacc parser may also throw an error in some cases
throw new InvalidQueryException(t.getMessage());
}
}
/**
* Creates a String representation of the query node tree in SQL syntax.
*
* @param root the root of the query node tree.
* @param resolver to resolve QNames.
* @return a String representation of the query node tree.
* @throws InvalidQueryException if the query node tree cannot be converted
* into a String representation due to restrictions in SQL.
*/
public static String toString(QueryRootNode root, NameResolver resolver)
throws InvalidQueryException {
return QueryFormat.toString(root, resolver);
}
/**
* Parses the statement and returns the root node of the QueryNode
* tree.
*
* @return the root node of the QueryNode tree.
*/
private QueryRootNode getRootNode() {
if (root == null) {
stmt.jjtAccept(this, null);
}
return root;
}
//----------------< JCRSQLParserVisitor >------------------------------------
public Object visit(SimpleNode node, Object data) {
// do nothing, should never be called actually
return data;
}
public Object visit(ASTQuery node, Object data) {
root = factory.createQueryRootNode();
root.setLocationNode(factory.createPathQueryNode(root));
// pass to select, from, where, ...
node.childrenAccept(this, root);
// use //* if no path has been set
PathQueryNode pathNode = root.getLocationNode();
pathNode.setAbsolute(true);
if (pathConstraints.size() == 0) {
LocationStepQueryNode step = factory.createLocationStepQueryNode(pathNode);
step.setNameTest(null);
step.setIncludeDescendants(true);
pathNode.addPathStep(step);
} else {
try {
while (pathConstraints.size() > 1) {
// merge path nodes
MergingPathQueryNode path = null;
for (Iterator it = pathConstraints.iterator(); it.hasNext();) {
path = (MergingPathQueryNode) it.next();
if (path.needsMerge()) {
break;
} else {
path = null;
}
}
if (path == null) {
throw new IllegalArgumentException("Invalid combination of jcr:path clauses");
} else {
pathConstraints.remove(path);
MergingPathQueryNode[] paths = (MergingPathQueryNode[]) pathConstraints.toArray(new MergingPathQueryNode[pathConstraints.size()]);
paths = path.doMerge(paths);
pathConstraints.clear();
pathConstraints.addAll(Arrays.asList(paths));
}
}
} catch (NoSuchElementException e) {
throw new IllegalArgumentException("Invalid combination of jcr:path clauses");
}
MergingPathQueryNode path = (MergingPathQueryNode) pathConstraints.get(0);
LocationStepQueryNode[] steps = path.getPathSteps();
for (int i = 0; i < steps.length; i++) {
LocationStepQueryNode step = factory.createLocationStepQueryNode(pathNode);
step.setNameTest(steps[i].getNameTest());
step.setIncludeDescendants(steps[i].getIncludeDescendants());
step.setIndex(steps[i].getIndex());
pathNode.addPathStep(step);
}
}
if (constraintNode.getNumOperands() == 1) {
// attach operand to last path step
LocationStepQueryNode[] steps = pathNode.getPathSteps();
steps[steps.length - 1].addPredicate(constraintNode.getOperands()[0]);
} else if (constraintNode.getNumOperands() > 1) {
// attach constraint to last path step
LocationStepQueryNode[] steps = pathNode.getPathSteps();
steps[steps.length - 1].addPredicate(constraintNode);
}
if (nodeTypeName != null) {
// add node type constraint
LocationStepQueryNode[] steps = pathNode.getPathSteps();
NodeTypeQueryNode nodeType
= factory.createNodeTypeQueryNode(steps[steps.length - 1], nodeTypeName);
steps[steps.length - 1].addPredicate(nodeType);
}
return root;
}
public Object visit(ASTSelectList node, Object data) {
final QueryRootNode root = (QueryRootNode) data;
node.childrenAccept(new DefaultParserVisitor() {
public Object visit(ASTIdentifier node, Object data) {
root.addSelectProperty(node.getName());
return data;
}
public Object visit(ASTExcerptFunction node, Object data) {
root.addSelectProperty(NameFactoryImpl.getInstance().create(Name.NS_REP_URI, "excerpt(.)"));
return data;
}
}, root);
return data;
}
public Object visit(ASTFromClause node, Object data) {
QueryRootNode root = (QueryRootNode) data;
return node.childrenAccept(new DefaultParserVisitor() {
public Object visit(ASTIdentifier node, Object data) {
if (!node.getName().equals(NameConstants.NT_BASE)) {
// node is either primary or mixin node type
nodeTypeName = node.getName();
}
return data;
}
}, root);
}
public Object visit(ASTWhereClause node, Object data) {
return node.childrenAccept(this, constraintNode);
}
public Object visit(ASTPredicate node, Object data) {
NAryQueryNode parent = (NAryQueryNode) data;
int type = node.getOperationType();
QueryNode predicateNode;
try {
final Name[] tmp = new Name[2];
final ASTLiteral[] value = new ASTLiteral[1];
node.childrenAccept(new DefaultParserVisitor() {
public Object visit(ASTIdentifier node, Object data) {
if (tmp[0] == null) {
tmp[0] = node.getName();
} else if (tmp[1] == null) {
tmp[1] = node.getName();
}
return data;
}
public Object visit(ASTLiteral node, Object data) {
value[0] = node;
return data;
}
public Object visit(ASTLowerFunction node, Object data) {
getIdentifier(node);
return data;
}
public Object visit(ASTUpperFunction node, Object data) {
getIdentifier(node);
return data;
}
private void getIdentifier(SimpleNode node) {
if (node.jjtGetNumChildren() > 0) {
Node n = node.jjtGetChild(0);
if (n instanceof ASTIdentifier) {
ASTIdentifier identifier = (ASTIdentifier) n;
if (tmp[0] == null) {
tmp[0] = identifier.getName();
} else if (tmp[1] == null) {
tmp[1] = identifier.getName();
}
}
}
}
}, data);
Name identifier = tmp[0];
if (identifier != null && identifier.equals(NameConstants.JCR_PATH)) {
if (tmp[1] != null) {
// simply ignore, this is a join of a mixin node type
} else {
createPathQuery(value[0].getValue(), parent.getType());
}
// done
return data;
}
if (type == QueryConstants.OPERATION_BETWEEN) {
AndQueryNode between = factory.createAndQueryNode(parent);
RelationQueryNode rel = createRelationQueryNode(between,
identifier, QueryConstants.OPERATION_GE_GENERAL, (ASTLiteral) node.children[1]);
node.childrenAccept(this, rel);
between.addOperand(rel);
rel = createRelationQueryNode(between,
identifier, QueryConstants.OPERATION_LE_GENERAL, (ASTLiteral) node.children[2]);
node.childrenAccept(this, rel);
between.addOperand(rel);
predicateNode = between;
} else if (type == QueryConstants.OPERATION_GE_GENERAL
|| type == QueryConstants.OPERATION_GT_GENERAL
|| type == QueryConstants.OPERATION_LE_GENERAL
|| type == QueryConstants.OPERATION_LT_GENERAL
|| type == QueryConstants.OPERATION_NE_GENERAL
|| type == QueryConstants.OPERATION_EQ_GENERAL) {
predicateNode = createRelationQueryNode(parent,
identifier, type, value[0]);
node.childrenAccept(this, predicateNode);
} else if (type == QueryConstants.OPERATION_LIKE) {
ASTLiteral pattern = value[0];
if (node.getEscapeString() != null) {
if (node.getEscapeString().length() == 1) {
// backslash is the escape character we use internally
pattern.setValue(translateEscaping(pattern.getValue(), node.getEscapeString().charAt(0), '\\'));
} else {
throw new IllegalArgumentException("ESCAPE string value must have length 1: '" + node.getEscapeString() + "'");
}
} else {
// no escape character specified.
// if the pattern contains any backslash characters we need
// to escape them.
pattern.setValue(pattern.getValue().replaceAll("\\\\", "\\\\\\\\"));
}
predicateNode = createRelationQueryNode(parent,
identifier, type, pattern);
node.childrenAccept(this, predicateNode);
} else if (type == QueryConstants.OPERATION_IN) {
OrQueryNode in = factory.createOrQueryNode(parent);
for (int i = 1; i < node.children.length; i++) {
RelationQueryNode rel = createRelationQueryNode(in,
identifier, QueryConstants.OPERATION_EQ_VALUE, (ASTLiteral) node.children[i]);
node.childrenAccept(this, rel);
in.addOperand(rel);
}
predicateNode = in;
} else if (type == QueryConstants.OPERATION_NULL
|| type == QueryConstants.OPERATION_NOT_NULL) {
predicateNode = createRelationQueryNode(parent,
identifier, type, null);
} else if (type == QueryConstants.OPERATION_SIMILAR) {
ASTLiteral literal;
if (node.children.length == 1) {
literal = (ASTLiteral) node.children[0];
} else {
literal = (ASTLiteral) node.children[1];
}
predicateNode = createRelationQueryNode(parent, identifier, type, literal);
} else if (type == QueryConstants.OPERATION_SPELLCHECK) {
predicateNode = createRelationQueryNode(parent,
NameConstants.JCR_PRIMARYTYPE, type,
(ASTLiteral) node.children[0]);
} else {
throw new IllegalArgumentException("Unknown operation type: " + type);
}
} catch (ArrayIndexOutOfBoundsException e) {
throw new IllegalArgumentException("Too few arguments in predicate");
}
if (predicateNode != null) {
parent.addOperand(predicateNode);
}
return data;
}
public Object visit(ASTOrExpression node, Object data) {
NAryQueryNode parent = (NAryQueryNode) data;
OrQueryNode orQuery = factory.createOrQueryNode(parent);
// pass to operands
node.childrenAccept(this, orQuery);
if (orQuery.getNumOperands() > 0) {
parent.addOperand(orQuery);
}
return parent;
}
public Object visit(ASTAndExpression node, Object data) {
NAryQueryNode parent = (NAryQueryNode) data;
AndQueryNode andQuery = factory.createAndQueryNode(parent);
// pass to operands
node.childrenAccept(this, andQuery);
if (andQuery.getNumOperands() > 0) {
parent.addOperand(andQuery);
}
return parent;
}
public Object visit(ASTNotExpression node, Object data) {
NAryQueryNode parent = (NAryQueryNode) data;
NotQueryNode notQuery = factory.createNotQueryNode(parent);
// pass to operand
node.childrenAccept(this, notQuery);
if (notQuery.getNumOperands() > 0) {
parent.addOperand(notQuery);
}
return parent;
}
public Object visit(ASTBracketExpression node, Object data) {
// bracket expression only has influence on how the syntax tree
// is created.
// simply pass on to children
return node.childrenAccept(this, data);
}
public Object visit(ASTLiteral node, Object data) {
// do nothing
return data;
}
public Object visit(ASTIdentifier node, Object data) {
// do nothing
return data;
}
public Object visit(ASTOrderByClause node, Object data) {
QueryRootNode root = (QueryRootNode) data;
OrderQueryNode order = factory.createOrderQueryNode(root);
root.setOrderNode(order);
node.childrenAccept(this, order);
return root;
}
public Object visit(ASTOrderSpec node, Object data) {
OrderQueryNode order = (OrderQueryNode) data;
final Name[] identifier = new Name[1];
// collect identifier
node.childrenAccept(new DefaultParserVisitor() {
public Object visit(ASTIdentifier node, Object data) {
identifier[0] = node.getName();
return data;
}
}, data);
OrderQueryNode.OrderSpec spec = new OrderQueryNode.OrderSpec(identifier[0], true);
order.addOrderSpec(spec);
node.childrenAccept(this, spec);
return data;
}
public Object visit(ASTAscendingOrderSpec node, Object data) {
// do nothing ascending is default anyway
return data;
}
public Object visit(ASTDescendingOrderSpec node, Object data) {
OrderQueryNode.OrderSpec spec = (OrderQueryNode.OrderSpec) data;
spec.setAscending(false);
return data;
}
public Object visit(ASTContainsExpression node, Object data) {
NAryQueryNode parent = (NAryQueryNode) data;
try {
Path relPath = null;
if (node.getPropertyName() != null) {
PathBuilder builder = new PathBuilder();
builder.addLast(node.getPropertyName());
relPath = builder.getPath();
}
TextsearchQueryNode tsNode = factory.createTextsearchQueryNode(parent, node.getQuery());
tsNode.setRelativePath(relPath);
tsNode.setReferencesProperty(true);
parent.addOperand(tsNode);
} catch (MalformedPathException e) {
// path is always valid
}
return parent;
}
public Object visit(ASTLowerFunction node, Object data) {
RelationQueryNode parent = (RelationQueryNode) data;
if (parent.getValueType() != QueryConstants.TYPE_STRING) {
String msg = "LOWER() function is only supported for String literal";
throw new IllegalArgumentException(msg);
}
parent.addOperand(factory.createPropertyFunctionQueryNode(parent, PropertyFunctionQueryNode.LOWER_CASE));
return parent;
}
public Object visit(ASTUpperFunction node, Object data) {
RelationQueryNode parent = (RelationQueryNode) data;
if (parent.getValueType() != QueryConstants.TYPE_STRING) {
String msg = "UPPER() function is only supported for String literal";
throw new IllegalArgumentException(msg);
}
parent.addOperand(factory.createPropertyFunctionQueryNode(parent, PropertyFunctionQueryNode.UPPER_CASE));
return parent;
}
public Object visit(ASTExcerptFunction node, Object data) {
// do nothing
return data;
}
//------------------------< internal >--------------------------------------
/**
* Creates a new {@link org.apache.jackrabbit.spi.commons.query.RelationQueryNode}.
*
* @param parent the parent node for the created RelationQueryNode.
* @param propertyName the property name for the relation.
* @param operationType the operation type.
* @param literal the literal value for the relation or
* null if the relation does not have a
* literal (e.g. IS NULL).
* @return a RelationQueryNode.
* @throws IllegalArgumentException if the literal value does not conform
* to its type. E.g. a malformed String representation of a date.
*/
private RelationQueryNode createRelationQueryNode(QueryNode parent,
Name propertyName,
int operationType,
ASTLiteral literal)
throws IllegalArgumentException {
RelationQueryNode node = null;
try {
Path relPath = null;
if (propertyName != null) {
PathBuilder builder = new PathBuilder();
builder.addLast(propertyName);
relPath = builder.getPath();
}
if (literal == null) {
node = factory.createRelationQueryNode(parent, operationType);
node.setRelativePath(relPath);
} else if (literal.getType() == QueryConstants.TYPE_DATE) {
SimpleDateFormat format = new SimpleDateFormat(DATE_PATTERN);
Date date = format.parse(literal.getValue());
node = factory.createRelationQueryNode(parent, operationType);
node.setRelativePath(relPath);
node.setDateValue(date);
} else if (literal.getType() == QueryConstants.TYPE_DOUBLE) {
double d = Double.parseDouble(literal.getValue());
node = factory.createRelationQueryNode(parent, operationType);
node.setRelativePath(relPath);
node.setDoubleValue(d);
} else if (literal.getType() == QueryConstants.TYPE_LONG) {
long l = Long.parseLong(literal.getValue());
node = factory.createRelationQueryNode(parent, operationType);
node.setRelativePath(relPath);
node.setLongValue(l);
} else if (literal.getType() == QueryConstants.TYPE_STRING) {
node = factory.createRelationQueryNode(parent, operationType);
node.setRelativePath(relPath);
node.setStringValue(literal.getValue());
} else if (literal.getType() == QueryConstants.TYPE_TIMESTAMP) {
Calendar c = ISO8601.parse(literal.getValue());
node = factory.createRelationQueryNode(parent, operationType);
node.setRelativePath(relPath);
node.setDateValue(c.getTime());
}
} catch (java.text.ParseException e) {
throw new IllegalArgumentException(e.toString());
} catch (NumberFormatException e) {
throw new IllegalArgumentException(e.toString());
} catch (MalformedPathException e) {
// path is always valid, but throw anyway
throw new IllegalArgumentException(e.getMessage());
}
if (node == null) {
throw new IllegalArgumentException("Unknown type for literal: " + literal.getType());
}
return node;
}
/**
* Creates LocationStepQueryNodes from a path.
*
* @param path the path pattern
* @param operation the type of the parent node
*/
private void createPathQuery(String path, int operation) {
MergingPathQueryNode pathNode = new MergingPathQueryNode(operation,
factory.createPathQueryNode(null).getValidJcrSystemNodeTypeNames());
pathNode.setAbsolute(true);
if (path.equals("/")) {
pathNode.addPathStep(factory.createLocationStepQueryNode(pathNode));
pathConstraints.add(pathNode);
return;
}
String[] names = path.split("/");
for (int i = 0; i < names.length; i++) {
if (names[i].length() == 0) {
if (i == 0) {
// root
pathNode.addPathStep(factory.createLocationStepQueryNode(pathNode));
} else {
// descendant '//' -> invalid path
// todo throw or ignore?
// we currently do not throw and add location step for an
// empty name (which is basically the root node)
pathNode.addPathStep(factory.createLocationStepQueryNode(pathNode));
}
} else {
int idx = names[i].indexOf('[');
String name;
int index = LocationStepQueryNode.NONE;
if (idx > -1) {
// contains index
name = names[i].substring(0, idx);
String suffix = names[i].substring(idx);
String indexStr = suffix.substring(1, suffix.length() - 1);
if (indexStr.equals("%")) {
// select all same name siblings
index = LocationStepQueryNode.NONE;
} else {
try {
index = Integer.parseInt(indexStr);
} catch (NumberFormatException e) {
log.warn("Unable to parse index for path element: " + names[i]);
}
}
if (name.equals("%")) {
name = null;
}
} else {
// no index specified
// - index defaults to 1 if there is an explicit name test
// - index defaults to NONE if name test is %
name = names[i];
if (name.equals("%")) {
name = null;
} else {
index = 1;
}
}
Name qName = null;
if (name != null) {
try {
qName = resolver.getQName(name);
} catch (NamespaceException e) {
throw new IllegalArgumentException("Illegal name: " + name);
} catch (NameException e) {
throw new IllegalArgumentException("Illegal name: " + name);
}
}
// if name test is % this means also search descendants
boolean descendant = name == null;
LocationStepQueryNode step = factory.createLocationStepQueryNode(pathNode);
step.setNameTest(qName);
step.setIncludeDescendants(descendant);
if (index > 0) {
step.setIndex(index);
}
pathNode.addPathStep(step);
}
}
pathConstraints.add(pathNode);
}
/**
* Translates a pattern using the escape character from into
* a pattern using the escape character to.
*
* @param pattern the pattern to translate
* @param from the currently used escape character.
* @param to the new escape character to use.
* @return the new pattern using the escape character to.
*/
private static String translateEscaping(String pattern, char from, char to) {
// if escape characters are the same OR pattern does not contain any
// escape characters -> simply return pattern as is.
if (from == to || (pattern.indexOf(from) < 0 && pattern.indexOf(to) < 0)) {
return pattern;
}
StringBuffer translated = new StringBuffer(pattern.length());
boolean escaped = false;
for (int i = 0; i < pattern.length(); i++) {
if (pattern.charAt(i) == from) {
if (escaped) {
translated.append(from);
escaped = false;
} else {
escaped = true;
}
} else if (pattern.charAt(i) == to) {
if (escaped) {
translated.append(to).append(to);
escaped = false;
} else {
translated.append(to).append(to);
}
} else {
if (escaped) {
translated.append(to);
escaped = false;
}
translated.append(pattern.charAt(i));
}
}
return translated.toString();
}
/**
* Extends the PathQueryNode with merging capability. A
* PathQueryNode n1 can be merged with another
* node n2 in the following case:
*
* n1 contains a location step at position X with
* a name test that matches any node and has the descending flag set. Where
* X < number of location steps.
* n2 contains no location step to match any node name and
* the sequence of name tests is the same as the sequence of name tests
* of n1.
* The merged node then contains a location step at position X
* with the name test of the location step at position X+1 and
* the descending flag set.
*
* The following path patterns:
* /foo/%/bar OR /foo/bar
* are merged into:
* /foo//bar.
*
* The path patterns:
* /foo/% AND NOT /foo/%/%
* are merged into:
* /foo/*
*/
private static class MergingPathQueryNode extends PathQueryNode {
/**
* The operation type of the parent node
*/
private int operation;
/**
* Creates a new MergingPathQueryNode with the operation
* type of a parent node. operation must be one of:
* {@link org.apache.jackrabbit.spi.commons.query.QueryNode#TYPE_OR},
* {@link org.apache.jackrabbit.spi.commons.query.QueryNode#TYPE_AND} or
* {@link org.apache.jackrabbit.spi.commons.query.QueryNode#TYPE_NOT}.
*
* @param operation the operation type of the parent node.
* @param validJcrSystemNodeTypeNames names of valid node types under
* /jcr:system.
*/
MergingPathQueryNode(
int operation, Collection validJcrSystemNodeTypeNames) {
super(null, validJcrSystemNodeTypeNames);
if (operation != QueryNode.TYPE_OR && operation != QueryNode.TYPE_AND && operation != QueryNode.TYPE_NOT) {
throw new IllegalArgumentException("operation");
}
this.operation = operation;
}
/**
* Merges this node with a node from nodes. If a merge
* is not possible an NoSuchElementException is thrown.
*
* @param nodes the nodes to try to merge with.
* @return the merged array containing a merged version of this node.
*/
MergingPathQueryNode[] doMerge(MergingPathQueryNode[] nodes) {
if (operation == QueryNode.TYPE_OR) {
return doOrMerge(nodes);
} else {
return doAndMerge(nodes);
}
}
/**
* Merges two nodes into a node which selects any child nodes of a
* given node.
*
* Example:
* The path patterns:
* /foo/% AND NOT /foo/%/%
* are merged into:
* /foo/*
*
* @param nodes the nodes to merge with.
* @return the merged nodes.
*/
private MergingPathQueryNode[] doAndMerge(MergingPathQueryNode[] nodes) {
if (operation == QueryNode.TYPE_AND) {
// check if there is an node with operation OP_AND_NOT
MergingPathQueryNode n = null;
for (int i = 0; i < nodes.length; i++) {
if (nodes[i].operation == QueryNode.TYPE_NOT) {
n = nodes[i];
nodes[i] = this;
}
}
if (n == null) {
throw new NoSuchElementException("Merging not possible with any node");
} else {
return n.doAndMerge(nodes);
}
}
// check if this node is valid as an operand
if (operands.size() < 3) {
throw new NoSuchElementException("Merging not possible");
}
int size = operands.size();
LocationStepQueryNode n1 = (LocationStepQueryNode) operands.get(size - 1);
LocationStepQueryNode n2 = (LocationStepQueryNode) operands.get(size - 2);
if (n1.getNameTest() != null || n2.getNameTest() != null
|| !n1.getIncludeDescendants() || !n2.getIncludeDescendants()) {
throw new NoSuchElementException("Merging not possible");
}
// find a node to merge with
MergingPathQueryNode matchedNode = null;
for (int i = 0; i < nodes.length; i++) {
if (nodes[i].operands.size() == operands.size() - 1) {
boolean match = true;
for (int j = 0; j < operands.size() - 1 && match; j++) {
LocationStepQueryNode step = (LocationStepQueryNode) operands.get(j);
LocationStepQueryNode other = (LocationStepQueryNode) nodes[i].operands.get(j);
match &= (step.getNameTest() == null) ? other.getNameTest() == null : step.getNameTest().equals(other.getNameTest());
}
if (match) {
matchedNode = nodes[i];
break;
}
}
}
if (matchedNode == null) {
throw new NoSuchElementException("Merging not possible with any node");
}
// change descendants flag to only match child nodes
// that's the result of the merge.
((LocationStepQueryNode) matchedNode.operands.get(matchedNode.operands.size() - 1)).setIncludeDescendants(false);
return nodes;
}
/**
* Merges two nodes into one node selecting a node on the
* descendant-or-self axis.
*
* Example:
* The following path patterns:
* /foo/%/bar OR /foo/bar
* are merged into:
* /foo//bar.
*
* @param nodes the node to merge.
* @return the merged nodes.
*/
private MergingPathQueryNode[] doOrMerge(MergingPathQueryNode[] nodes) {
// compact this
MergingPathQueryNode compacted = new MergingPathQueryNode(
QueryNode.TYPE_OR, getValidJcrSystemNodeTypeNames());
for (Iterator it = operands.iterator(); it.hasNext();) {
LocationStepQueryNode step = (LocationStepQueryNode) it.next();
if (step.getIncludeDescendants() && step.getNameTest() == null) {
// check if has next
if (it.hasNext()) {
LocationStepQueryNode next = (LocationStepQueryNode) it.next();
next.setIncludeDescendants(true);
compacted.addPathStep(next);
} else {
compacted.addPathStep(step);
}
} else {
compacted.addPathStep(step);
}
}
MergingPathQueryNode matchedNode = null;
for (int i = 0; i < nodes.length; i++) {
// loop over the steps and compare the names
if (nodes[i].operands.size() == compacted.operands.size()) {
boolean match = true;
Iterator compactedSteps = compacted.operands.iterator();
Iterator otherSteps = nodes[i].operands.iterator();
while (match && compactedSteps.hasNext()) {
LocationStepQueryNode n1 = (LocationStepQueryNode) compactedSteps.next();
LocationStepQueryNode n2 = (LocationStepQueryNode) otherSteps.next();
match &= (n1.getNameTest() == null) ? n2.getNameTest() == null : n1.getNameTest().equals(n2.getNameTest());
}
if (match) {
matchedNode = nodes[i];
break;
}
}
}
if (matchedNode == null) {
throw new NoSuchElementException("Merging not possible with any node.");
}
// construct new list
List mergedList = new ArrayList(Arrays.asList(nodes));
mergedList.remove(matchedNode);
mergedList.add(compacted);
return (MergingPathQueryNode[]) mergedList.toArray(new MergingPathQueryNode[mergedList.size()]);
}
/**
* Returns true if this node needs merging; false
* otherwise.
*
* @return true if this node needs merging; false
* otherwise.
*/
boolean needsMerge() {
for (Iterator it = operands.iterator(); it.hasNext();) {
LocationStepQueryNode step = (LocationStepQueryNode) it.next();
if (step.getIncludeDescendants() && step.getNameTest() == null) {
return true;
}
}
return false;
}
}
}