2 * Copyright (c) 2019 Pantheon Technologies, s.r.o. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.yangtools.yang.xpath.impl;
10 import static java.util.Objects.requireNonNull;
11 import static org.opendaylight.yangtools.yang.xpath.impl.ParseTreeUtils.getChild;
12 import static org.opendaylight.yangtools.yang.xpath.impl.ParseTreeUtils.illegalShape;
13 import static org.opendaylight.yangtools.yang.xpath.impl.ParseTreeUtils.verifyToken;
15 import com.google.common.collect.ImmutableSet;
16 import java.util.ArrayList;
17 import java.util.Collection;
18 import java.util.List;
19 import javax.xml.xpath.XPathExpressionException;
20 import org.antlr.v4.runtime.CharStreams;
21 import org.antlr.v4.runtime.CommonTokenStream;
22 import org.antlr.v4.runtime.tree.ParseTree;
23 import org.opendaylight.yangtools.yang.common.QName;
24 import org.opendaylight.yangtools.yang.common.YangNamespaceContext;
25 import org.opendaylight.yangtools.yang.xpath.api.YangBinaryOperator;
26 import org.opendaylight.yangtools.yang.xpath.api.YangExpr;
27 import org.opendaylight.yangtools.yang.xpath.api.YangLiteralExpr;
28 import org.opendaylight.yangtools.yang.xpath.api.YangLocationPath;
29 import org.opendaylight.yangtools.yang.xpath.api.YangLocationPath.Step;
30 import org.opendaylight.yangtools.yang.xpath.api.YangQNameExpr;
31 import org.opendaylight.yangtools.yang.xpath.api.YangXPathAxis;
32 import org.opendaylight.yangtools.yang.xpath.api.YangXPathMathMode;
33 import org.opendaylight.yangtools.yang.xpath.api.YangXPathMathSupport;
34 import org.opendaylight.yangtools.yang.xpath.impl.instanceIdentifierParser.EqQuotedStringContext;
35 import org.opendaylight.yangtools.yang.xpath.impl.instanceIdentifierParser.InstanceIdentifierContext;
36 import org.opendaylight.yangtools.yang.xpath.impl.instanceIdentifierParser.KeyPredicateContext;
37 import org.opendaylight.yangtools.yang.xpath.impl.instanceIdentifierParser.KeyPredicateExprContext;
38 import org.opendaylight.yangtools.yang.xpath.impl.instanceIdentifierParser.LeafListPredicateContext;
39 import org.opendaylight.yangtools.yang.xpath.impl.instanceIdentifierParser.LeafListPredicateExprContext;
40 import org.opendaylight.yangtools.yang.xpath.impl.instanceIdentifierParser.NodeIdentifierContext;
41 import org.opendaylight.yangtools.yang.xpath.impl.instanceIdentifierParser.PathArgumentContext;
42 import org.opendaylight.yangtools.yang.xpath.impl.instanceIdentifierParser.PosContext;
43 import org.opendaylight.yangtools.yang.xpath.impl.instanceIdentifierParser.PredicateContext;
44 import org.opendaylight.yangtools.yang.xpath.impl.instanceIdentifierParser.QuotedStringContext;
46 final class InstanceIdentifierParser {
47 private final YangNamespaceContext namespaceContext;
48 private final YangXPathMathSupport mathSupport;
50 InstanceIdentifierParser(final YangNamespaceContext namespaceContext, final YangXPathMathMode mathMode) {
51 this.namespaceContext = requireNonNull(namespaceContext);
52 this.mathSupport = mathMode.getSupport();
55 YangLocationPath interpretAsInstanceIdentifier(final YangLiteralExpr expr) throws XPathExpressionException {
56 final xpathLexer lexer = new xpathLexer(CharStreams.fromString(expr.getLiteral()));
57 final instanceIdentifierParser parser = new instanceIdentifierParser(new CommonTokenStream(lexer));
58 final CapturingErrorListener listener = new CapturingErrorListener();
59 lexer.removeErrorListeners();
60 lexer.addErrorListener(listener);
61 parser.removeErrorListeners();
62 parser.addErrorListener(listener);
64 final InstanceIdentifierContext id = parser.instanceIdentifier();
65 listener.reportError();
67 final int length = id.getChildCount();
68 final List<Step> steps = new ArrayList<>(length / 2);
69 for (int i = 1; i < length; i += 2) {
70 steps.add(parsePathArgument(getChild(id, PathArgumentContext.class, i)));
73 return YangLocationPath.of(true, steps);
76 private Step parsePathArgument(final PathArgumentContext expr) {
77 final QName qname = parseQName(getChild(expr, NodeIdentifierContext.class, 0));
78 switch (expr.getChildCount()) {
80 return YangXPathAxis.CHILD.asStep(qname, ImmutableSet.of());
82 return YangXPathAxis.CHILD.asStep(qname, parsePredicate(getChild(expr, PredicateContext.class, 1)));
84 throw illegalShape(expr);
88 private Collection<YangExpr> parsePredicate(final PredicateContext expr) {
89 final ParseTree first = expr.getChild(0);
90 if (first instanceof LeafListPredicateContext) {
91 return ImmutableSet.of(YangBinaryOperator.EQUALS.exprWith(YangLocationPath.self(),
92 parseEqStringValue(getChild(((LeafListPredicateContext) first)
93 .getChild(LeafListPredicateExprContext.class, 0), EqQuotedStringContext.class, 1))));
94 } else if (first instanceof PosContext) {
95 return ImmutableSet.of(YangBinaryOperator.EQUALS.exprWith(FunctionSupport.POSITION,
96 mathSupport.createNumber(((PosContext) first).getToken(instanceIdentifierParser.PositiveIntegerValue, 0)
100 final int length = expr.getChildCount();
101 final List<YangExpr> ret = new ArrayList<>(length);
102 for (int i = 0; i < length; ++i) {
103 final KeyPredicateExprContext pred = getChild(expr, KeyPredicateContext.class, i)
104 .getChild(KeyPredicateExprContext.class, 0);
105 ret.add(YangBinaryOperator.EQUALS.exprWith(
106 YangQNameExpr.of(parseQName(getChild(pred, NodeIdentifierContext.class, 0))),
107 parseEqStringValue(getChild(pred, EqQuotedStringContext.class, 1))));
114 private QName parseQName(final NodeIdentifierContext expr) {
115 return namespaceContext.createQName(
116 verifyToken(expr, 0, instanceIdentifierParser.Identifier).getText(),
117 verifyToken(expr, 2, instanceIdentifierParser.Identifier).getText());
120 private static YangLiteralExpr parseEqStringValue(final EqQuotedStringContext expr) {
121 return YangLiteralExpr.of(verifyToken(getChild(expr, QuotedStringContext.class, expr.getChildCount() - 1), 1,
122 instanceIdentifierParser.STRING).getText());