[ONOS-3898/4069] Yang Utils Extension to support RPC/Notification/Choice/Case/Union
Change-Id: I405852caff3464719e8e586fa8e9ae9b6ed043ff
diff --git a/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/listeners/CaseListener.java b/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/listeners/CaseListener.java
new file mode 100644
index 0000000..b98bd12
--- /dev/null
+++ b/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/listeners/CaseListener.java
@@ -0,0 +1,157 @@
+/*
+ * Copyright 2014-2016 Open Networking Laboratory
+ *
+ * Licensed 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.onosproject.yangutils.parser.impl.listeners;
+
+import org.onosproject.yangutils.datamodel.YangCase;
+import org.onosproject.yangutils.datamodel.YangChoice;
+import org.onosproject.yangutils.datamodel.YangNode;
+import org.onosproject.yangutils.datamodel.exceptions.DataModelException;
+import org.onosproject.yangutils.parser.Parsable;
+import org.onosproject.yangutils.parser.antlrgencode.GeneratedYangParser;
+import org.onosproject.yangutils.parser.exceptions.ParserException;
+import org.onosproject.yangutils.parser.impl.TreeWalkListener;
+
+import static org.onosproject.yangutils.datamodel.utils.GeneratedLanguage.JAVA_GENERATION;
+import static org.onosproject.yangutils.datamodel.utils.YangDataModelFactory.getYangCaseNode;
+import static org.onosproject.yangutils.parser.impl.parserutils.ListenerCollisionDetector.detectCollidingChildUtil;
+import static org.onosproject.yangutils.parser.impl.parserutils.ListenerErrorLocation.ENTRY;
+import static org.onosproject.yangutils.parser.impl.parserutils.ListenerErrorLocation.EXIT;
+import static org.onosproject.yangutils.parser.impl.parserutils.ListenerErrorMessageConstruction.constructExtendedListenerErrorMessage;
+import static org.onosproject.yangutils.parser.impl.parserutils.ListenerErrorMessageConstruction.constructListenerErrorMessage;
+import static org.onosproject.yangutils.parser.impl.parserutils.ListenerErrorType.INVALID_HOLDER;
+import static org.onosproject.yangutils.parser.impl.parserutils.ListenerErrorType.MISSING_CURRENT_HOLDER;
+import static org.onosproject.yangutils.parser.impl.parserutils.ListenerErrorType.MISSING_HOLDER;
+import static org.onosproject.yangutils.parser.impl.parserutils.ListenerErrorType.UNHANDLED_PARSED_DATA;
+import static org.onosproject.yangutils.parser.impl.parserutils.ListenerUtil.getValidIdentifier;
+import static org.onosproject.yangutils.parser.impl.parserutils.ListenerValidation.checkStackIsNotEmpty;
+import static org.onosproject.yangutils.parser.impl.parserutils.ListenerValidation.validateCardinalityMaxOne;
+import static org.onosproject.yangutils.utils.YangConstructType.CASE_DATA;
+import static org.onosproject.yangutils.utils.YangConstructType.DESCRIPTION_DATA;
+import static org.onosproject.yangutils.utils.YangConstructType.REFERENCE_DATA;
+import static org.onosproject.yangutils.utils.YangConstructType.STATUS_DATA;
+import static org.onosproject.yangutils.utils.YangConstructType.WHEN_DATA;
+
+/*
+ * Reference: RFC6020 and YANG ANTLR Grammar
+ *
+ * ABNF grammar as per RFC6020
+ * case-stmt = case-keyword sep identifier-arg-str optsep
+ * (";" /
+ * "{" stmtsep
+ * ;; these stmts can appear in any order
+ * [when-stmt stmtsep]
+ * *(if-feature-stmt stmtsep)
+ * [status-stmt stmtsep]
+ * [description-stmt stmtsep]
+ * [reference-stmt stmtsep]
+ * *(data-def-stmt stmtsep)
+ * "}")
+ *
+ * ANTLR grammar rule
+ * caseStatement : CASE_KEYWORD identifier (STMTEND | LEFT_CURLY_BRACE (whenStatement | ifFeatureStatement
+ * | statusStatement | descriptionStatement | referenceStatement | dataDefStatement)* RIGHT_CURLY_BRACE);
+ */
+
+/**
+ * Implements listener based call back function corresponding to the "case" rule
+ * defined in ANTLR grammar file for corresponding ABNF rule in RFC 6020.
+ */
+public final class CaseListener {
+
+ /**
+ * Create a new case listener.
+ */
+ private CaseListener() {
+ }
+
+ /**
+ * It is called when parser enters grammar rule (case), it perform
+ * validations and updates the data model tree.
+ *
+ * @param listener listener's object
+ * @param ctx context object of the grammar rule
+ */
+ public static void processCaseEntry(TreeWalkListener listener,
+ GeneratedYangParser.CaseStatementContext ctx) {
+
+ // Check for stack to be non empty.
+ checkStackIsNotEmpty(listener, MISSING_HOLDER, CASE_DATA, ctx.identifier().getText(), ENTRY);
+
+ // Check validity of identifier and remove double quotes.
+ String identifier = getValidIdentifier(ctx.identifier().getText(), CASE_DATA, ctx);
+
+ // Validate sub statement cardinality.
+ validateSubStatementsCardinality(ctx);
+
+ Parsable curData = listener.getParsedDataStack().peek();
+
+ // Check for identifier collision
+ int line = ctx.getStart().getLine();
+ int charPositionInLine = ctx.getStart().getCharPositionInLine();
+ detectCollidingChildUtil(listener, line, charPositionInLine, identifier, CASE_DATA);
+
+ if (curData instanceof YangChoice) {
+ YangCase caseNode = getYangCaseNode(JAVA_GENERATION);
+ caseNode.setName(identifier);
+ YangNode curNode = (YangNode) curData;
+ try {
+ curNode.addChild(caseNode);
+ } catch (DataModelException e) {
+ throw new ParserException(constructExtendedListenerErrorMessage(UNHANDLED_PARSED_DATA,
+ CASE_DATA, ctx.identifier().getText(), ENTRY, e.getMessage()));
+ }
+ listener.getParsedDataStack().push(caseNode);
+ } else {
+ throw new ParserException(constructListenerErrorMessage(INVALID_HOLDER, CASE_DATA,
+ ctx.identifier().getText(), ENTRY));
+ }
+ }
+
+ /**
+ * It is called when parser exits from grammar rule (case), it perform
+ * validations and update the data model tree.
+ *
+ * @param listener Listener's object
+ * @param ctx context object of the grammar rule
+ */
+ public static void processCaseExit(TreeWalkListener listener,
+ GeneratedYangParser.CaseStatementContext ctx) {
+
+ // Check for stack to be non empty.
+ checkStackIsNotEmpty(listener, MISSING_HOLDER, CASE_DATA, ctx.identifier().getText(), EXIT);
+
+ if (listener.getParsedDataStack().peek() instanceof YangCase) {
+ listener.getParsedDataStack().pop();
+ } else {
+ throw new ParserException(constructListenerErrorMessage(MISSING_CURRENT_HOLDER, CASE_DATA,
+ ctx.identifier().getText(), EXIT));
+ }
+ }
+
+ /**
+ * Validates the cardinality of case sub-statements as per grammar.
+ *
+ * @param ctx context object of the grammar rule
+ */
+ private static void validateSubStatementsCardinality(GeneratedYangParser.CaseStatementContext ctx) {
+
+ validateCardinalityMaxOne(ctx.whenStatement(), WHEN_DATA, CASE_DATA, ctx.identifier().getText());
+ validateCardinalityMaxOne(ctx.statusStatement(), STATUS_DATA, CASE_DATA, ctx.identifier().getText());
+ validateCardinalityMaxOne(ctx.descriptionStatement(), DESCRIPTION_DATA, CASE_DATA, ctx.identifier().getText());
+ validateCardinalityMaxOne(ctx.referenceStatement(), REFERENCE_DATA, CASE_DATA, ctx.identifier().getText());
+ }
+}