Introducing Antlr4 for cpsPath parsing

[cps.git] / cps-path-parser / src / main / java / org / onap / cps / cpspath / parser / CpsPathBuilder.java

diff --git a/cps-path-parser/src/main/java/org/onap/cps/cpspath/parser/CpsPathBuilder.java b/cps-path-parser/src/main/java/org/onap/cps/cpspath/parser/CpsPathBuilder.java
new file mode 100644 (file)
index 0000000..83e076d
--- /dev/null
+++ b/cps-path-parser/src/main/java/org/onap/cps/cpspath/parser/CpsPathBuilder.java
@@ -0,0 +1,107 @@
+package org.onap.cps.cpspath.parser;
+/*
+ *  ============LICENSE_START=======================================================
+ *  Copyright (C) 2021 Nordix Foundation
+ *  ================================================================================
+ *  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.
+ *
+ *  SPDX-License-Identifier: Apache-2.0
+ *  ============LICENSE_END=========================================================
+ */
+
+import java.util.HashMap;
+import java.util.Map;
+import org.onap.cps.cpspath.parser.antlr4.CpsPathBaseListener;
+import org.onap.cps.cpspath.parser.antlr4.CpsPathParser.AncestorAxisContext;
+import org.onap.cps.cpspath.parser.antlr4.CpsPathParser.CpsPathWithDescendantAndLeafConditionsContext;
+import org.onap.cps.cpspath.parser.antlr4.CpsPathParser.CpsPathWithDescendantContext;
+import org.onap.cps.cpspath.parser.antlr4.CpsPathParser.CpsPathWithSingleLeafConditionContext;
+import org.onap.cps.cpspath.parser.antlr4.CpsPathParser.LeafConditionContext;
+import org.onap.cps.cpspath.parser.antlr4.CpsPathParser.MultipleValueConditionsContext;
+import org.onap.cps.cpspath.parser.antlr4.CpsPathParser.PrefixContext;
+import org.onap.cps.cpspath.parser.antlr4.CpsPathParser.SingleValueConditionContext;
+
+public class CpsPathBuilder extends CpsPathBaseListener {
+
+    final CpsPathQuery cpsPathQuery = new CpsPathQuery();
+
+    final Map<String, Object> leavesData = new HashMap<>();
+
+    @Override
+    public void exitPrefix(final PrefixContext ctx) {
+        cpsPathQuery.setXpathPrefix(ctx.getText());
+    }
+
+    @Override
+    public void exitLeafCondition(final LeafConditionContext ctx) {
+        Object comparisonValue = null;
+        if (ctx.IntegerLiteral() != null) {
+            comparisonValue = Integer.valueOf(ctx.IntegerLiteral().getText());
+        }
+        if (ctx.StringLiteral() != null) {
+            comparisonValue = stripFirstAndLastCharacter(ctx.StringLiteral().getText());
+        } else if (comparisonValue == null) {
+            throw new IllegalStateException("Unsupported comparison value encountered in expression" + ctx.getText());
+        }
+        leavesData.put(ctx.leafName().getText(), comparisonValue);
+    }
+
+    @Override
+    public void enterSingleValueCondition(final SingleValueConditionContext ctx) {
+        leavesData.clear();
+    }
+
+    @Override
+    public void enterMultipleValueConditions(final MultipleValueConditionsContext ctx) {
+        leavesData.clear();
+    }
+
+    @Override
+    public void exitSingleValueCondition(final SingleValueConditionContext ctx) {
+        final String leafName = ctx.leafCondition().leafName().getText();
+        cpsPathQuery.setLeafName(leafName);
+        cpsPathQuery.setLeafValue(leavesData.get(leafName));
+    }
+
+    @Override
+    public void exitCpsPathWithSingleLeafCondition(final CpsPathWithSingleLeafConditionContext ctx) {
+        cpsPathQuery.setCpsPathQueryType(CpsPathQueryType.XPATH_LEAF_VALUE);
+    }
+
+    @Override
+    public void exitCpsPathWithDescendant(final CpsPathWithDescendantContext ctx) {
+        cpsPathQuery.setCpsPathQueryType(CpsPathQueryType.XPATH_HAS_DESCENDANT_ANYWHERE);
+        cpsPathQuery.setDescendantName(cpsPathQuery.getXpathPrefix().substring(1));
+    }
+
+    @Override
+    public void exitCpsPathWithDescendantAndLeafConditions(
+        final CpsPathWithDescendantAndLeafConditionsContext ctx) {
+        cpsPathQuery.setCpsPathQueryType(CpsPathQueryType.XPATH_HAS_DESCENDANT_WITH_LEAF_VALUES);
+        cpsPathQuery.setDescendantName(cpsPathQuery.getXpathPrefix().substring(1));
+        cpsPathQuery.setLeavesData(leavesData);
+    }
+
+    @Override
+    public void exitAncestorAxis(final AncestorAxisContext ctx) {
+        cpsPathQuery.setAncestorSchemaNodeIdentifier(ctx.ancestorPath().getText());
+    }
+
+    CpsPathQuery build() {
+        return cpsPathQuery;
+    }
+
+    private static String stripFirstAndLastCharacter(final String wrappedString) {
+        return wrappedString.substring(1, wrappedString.length() - 1);
+    }
+
+}