yang/yang-parser-impl/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 java.util.Set;
  13 import java.util.function.Predicate;
  14 import org.antlr.v4.runtime.CharStreams;
  15 import org.antlr.v4.runtime.CommonTokenStream;
  16 import org.opendaylight.yangtools.antlrv4.code.gen.IfFeatureExpressionLexer;
  17 import org.opendaylight.yangtools.antlrv4.code.gen.IfFeatureExpressionParser;
  18 import org.opendaylight.yangtools.antlrv4.code.gen.IfFeatureExpressionParser.Identifier_ref_argContext;
  19 import org.opendaylight.yangtools.antlrv4.code.gen.IfFeatureExpressionParser.If_feature_exprContext;
  20 import org.opendaylight.yangtools.antlrv4.code.gen.IfFeatureExpressionParser.If_feature_factorContext;
  21 import org.opendaylight.yangtools.antlrv4.code.gen.IfFeatureExpressionParser.If_feature_termContext;
  22 import org.opendaylight.yangtools.antlrv4.code.gen.IfFeatureExpressionParserBaseVisitor;
  23 import org.opendaylight.yangtools.yang.common.QName;
  24 import org.opendaylight.yangtools.yang.parser.spi.meta.StmtContext;
  25 import org.opendaylight.yangtools.yang.parser.spi.meta.StmtContextUtils;
  26 import org.opendaylight.yangtools.yang.parser.spi.source.SourceException;
  27
  28 final class IfFeaturePredicateVisitor extends IfFeatureExpressionParserBaseVisitor<Predicate<Set<QName>>> {
  29     private final StmtContext<?, ?, ?> stmtCtx;
  30
  31     private IfFeaturePredicateVisitor(final StmtContext<?, ?, ?> ctx) {
  32         this.stmtCtx = requireNonNull(ctx);
  33     }
  34
  35     static Predicate<Set<QName>> parseIfFeatureExpression(final StmtContext<?, ?, ?> ctx, final String value) {
  36         final IfFeatureExpressionLexer lexer = new IfFeatureExpressionLexer(CharStreams.fromString(value));
  37         final CommonTokenStream tokens = new CommonTokenStream(lexer);
  38         final IfFeatureExpressionParser parser = new IfFeatureExpressionParser(tokens);
  39
  40         return new IfFeaturePredicateVisitor(ctx).visit(parser.if_feature_expr());
  41     }
  42
  43     @Override
  44     public Predicate<Set<QName>> visitIf_feature_expr(final If_feature_exprContext ctx) {
  45         if (ctx.if_feature_expr() == null) {
  46             return visitIf_feature_term(ctx.if_feature_term());
  47         }
  48
  49         return visitIf_feature_term(ctx.if_feature_term()).or(visitIf_feature_expr(ctx.if_feature_expr()));
  50     }
  51
  52     @Override
  53     public Predicate<Set<QName>> visitIf_feature_term(final If_feature_termContext ctx) {
  54         if (ctx.if_feature_term() == null) {
  55             return visitIf_feature_factor(ctx.if_feature_factor());
  56         }
  57
  58         return visitIf_feature_factor(ctx.if_feature_factor()).and(visitIf_feature_term(ctx.if_feature_term()));
  59     }
  60
  61     @Override
  62     public Predicate<Set<QName>> visitIf_feature_factor(final If_feature_factorContext ctx) {
  63         if (ctx.if_feature_expr() != null) {
  64             return visitIf_feature_expr(ctx.if_feature_expr());
  65         } else if (ctx.if_feature_factor() != null) {
  66             return visitIf_feature_factor(ctx.if_feature_factor()).negate();
  67         } else if (ctx.identifier_ref_arg() != null) {
  68             return visitIdentifier_ref_arg(ctx.identifier_ref_arg());
  69         }
  70
  71         throw new SourceException("Unexpected grammar context during parsing of IfFeature expression. "
  72                 + "Most probably IfFeature grammar has been changed.", stmtCtx.getStatementSourceReference());
  73     }
  74
  75     @Override
  76     public Predicate<Set<QName>> visitIdentifier_ref_arg(final Identifier_ref_argContext ctx) {
  77         final QName featureQName = StmtContextUtils.qnameFromArgument(stmtCtx, ctx.getText());
  78         return setQNames -> setQNames.contains(featureQName);
  79     }
  80 }