parser/yang-parser-rfc7950/src/main/java/org/opendaylight/yangtools/yang/parser/rfc7950/stmt/if_feature/IfFeaturePredicateVisitor.java

   1 /*
   2  * Copyright (c) 2017 Pantheon Technologies, s.r.o. and others.  All rights reserved.
   3  *
   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
   7  */
   8 package org.opendaylight.yangtools.yang.parser.rfc7950.stmt.if_feature;
   9
  10 import static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.collect.ImmutableSet;
  13 import java.util.ArrayList;
  14 import java.util.List;
  15 import org.antlr.v4.runtime.CharStreams;
  16 import org.antlr.v4.runtime.CommonTokenStream;
  17 import org.eclipse.jdt.annotation.NonNullByDefault;
  18 import org.eclipse.jdt.annotation.Nullable;
  19 import org.opendaylight.yangtools.yang.model.api.stmt.IfFeatureExpr;
  20 import org.opendaylight.yangtools.yang.parser.antlr.IfFeatureExpressionLexer;
  21 import org.opendaylight.yangtools.yang.parser.antlr.IfFeatureExpressionParser;
  22 import org.opendaylight.yangtools.yang.parser.antlr.IfFeatureExpressionParser.Identifier_ref_argContext;
  23 import org.opendaylight.yangtools.yang.parser.antlr.IfFeatureExpressionParser.If_feature_exprContext;
  24 import org.opendaylight.yangtools.yang.parser.antlr.IfFeatureExpressionParser.If_feature_factorContext;
  25 import org.opendaylight.yangtools.yang.parser.antlr.IfFeatureExpressionParser.If_feature_termContext;
  26 import org.opendaylight.yangtools.yang.parser.antlr.IfFeatureExpressionParserBaseVisitor;
  27 import org.opendaylight.yangtools.yang.parser.rfc7950.antlr.SourceExceptionParser;
  28 import org.opendaylight.yangtools.yang.parser.spi.meta.StmtContext;
  29 import org.opendaylight.yangtools.yang.parser.spi.meta.StmtContextUtils;
  30 import org.opendaylight.yangtools.yang.parser.spi.source.SourceException;
  31
  32 // FIXME: YANGTOOLS-1396: refactor on top of vanilla IfFeatureExpressionParser
  33 @NonNullByDefault
  34 final class IfFeaturePredicateVisitor extends IfFeatureExpressionParserBaseVisitor<IfFeatureExpr> {
  35     private final StmtContext<?, ?, ?> stmtCtx;
  36
  37     private IfFeaturePredicateVisitor(final StmtContext<?, ?, ?> ctx) {
  38         this.stmtCtx = requireNonNull(ctx);
  39     }
  40
  41     static IfFeatureExpr parseIfFeatureExpression(final StmtContext<?, ?, ?> ctx, final String value) {
  42         final IfFeatureExpressionLexer lexer = new IfFeatureExpressionLexer(CharStreams.fromString(value));
  43         final IfFeatureExpressionParser parser = new IfFeatureExpressionParser(new CommonTokenStream(lexer));
  44         final IfFeatureExpr ret = new IfFeaturePredicateVisitor(ctx).visit(SourceExceptionParser.parse(lexer, parser,
  45             parser::if_feature_expr, ctx.sourceReference()));
  46
  47         return ret;
  48     }
  49
  50     @Override
  51     public IfFeatureExpr visitIf_feature_expr(final @Nullable If_feature_exprContext ctx) {
  52         return IfFeatureExpr.or(ctx.if_feature_term().stream()
  53             .map(this::visitIf_feature_term)
  54             .collect(ImmutableSet.toImmutableSet()));
  55     }
  56
  57     @Override
  58     public IfFeatureExpr visitIf_feature_term(final @Nullable If_feature_termContext ctx) {
  59         final IfFeatureExpr factor = visitIf_feature_factor(ctx.if_feature_factor());
  60         final List<If_feature_termContext> terms = ctx.if_feature_term();
  61         if (terms == null || terms.isEmpty()) {
  62             return factor;
  63         }
  64         final List<IfFeatureExpr> factors = new ArrayList<>(terms.size() + 1);
  65         factors.add(factor);
  66         for (If_feature_termContext term : terms) {
  67             factors.add(visitIf_feature_term(term));
  68         }
  69         return IfFeatureExpr.and(ImmutableSet.copyOf(factors));
  70     }
  71
  72     @Override
  73     public IfFeatureExpr visitIf_feature_factor(final @Nullable If_feature_factorContext ctx) {
  74         if (ctx.if_feature_expr() != null) {
  75             return visitIf_feature_expr(ctx.if_feature_expr());
  76         } else if (ctx.if_feature_factor() != null) {
  77             return visitIf_feature_factor(ctx.if_feature_factor()).negate();
  78         } else if (ctx.identifier_ref_arg() != null) {
  79             return visitIdentifier_ref_arg(ctx.identifier_ref_arg());
  80         }
  81
  82         throw new SourceException("Unexpected grammar context during parsing of IfFeature expression. "
  83                 + "Most probably IfFeature grammar has been changed.", stmtCtx);
  84     }
  85
  86     @Override
  87     public IfFeatureExpr visitIdentifier_ref_arg(final @Nullable Identifier_ref_argContext ctx) {
  88         return IfFeatureExpr.isPresent(StmtContextUtils.parseNodeIdentifier(stmtCtx, ctx.getText()));
  89     }
  90 }