Merge pull request #141 from kieler/tik/semantic-filtering-parse-util

Wrote a util for parsing semantic filter rules

plugins/de.cau.cs.kieler.klighd/src/de/cau/cs/kieler/klighd/filtering/parser/SemanticFilterRuleParserUtil.java

@@ -0,0 +1,98 @@
+/*
+ * KIELER - Kiel Integrated Environment for Layout Eclipse RichClient
+ *
+ * http://rtsys.informatik.uni-kiel.de/kieler
+ * 
+ * Copyright 2022 by
+ * + Kiel University
+ *   + Department of Computer Science
+ *     + Real-Time and Embedded Systems Group
+ * 
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package de.cau.cs.kieler.klighd.filtering.parser;
+
+import de.cau.cs.kieler.klighd.filtering.SemanticFilterRule;
+import de.cau.cs.kieler.klighd.filtering.SemanticFilterRuleUtil;
+import de.cau.cs.kieler.klighd.filtering.parser.SemanticFilterRuleParser.InvalidSyntaxException;
+
+/**
+ * Util for easily parsing rules.
+ * 
+ * @author tik
+ */
+public abstract class SemanticFilterRuleParserUtil {
+
+    /** Instance of parser. Just one is enough. */
+    private static final SemanticFilterRuleParser PARSER = new SemanticFilterRuleParser();
+
+    /**
+     * Parses a semantic filter rule expression and returns the {@link SemanticFilterRule}.
+     * 
+     * @param ruleString
+     *            The semantic filter rule expression
+     * @return The semantic filter rule
+     * @see SemanticFilterRuleParser#parse(String)
+     * @throws InvalidSyntaxException
+     */
+    public static SemanticFilterRule parse(String ruleString) throws InvalidSyntaxException {
+        return PARSER.parse(ruleString);
+    }
+
+    /**
+     * Parses a semantic filter rule expression and returns the {@link SemanticFilterRule} with
+     * given ruleName.
+     * 
+     * @param ruleString
+     *            The semantic filter rule expression
+     * @param ruleName
+     *            The rule name
+     * @return The semantic filter rule
+     * @see SemanticFilterRuleParser#parse(String)
+     * @throws InvalidSyntaxException
+     */
+    public static SemanticFilterRule parse(String ruleString, String ruleName)
+            throws InvalidSyntaxException {
+        return SemanticFilterRuleUtil.addRuleName(ruleName, PARSER.parse(ruleString));
+    }
+
+    /**
+     * Tries parsing a semantic filter rule expression. Returns the {@link SemanticFilterRule} or
+     * {@code null} if the syntax is invalid.
+     * 
+     * @param ruleString
+     *            The semantic filter rule expression
+     * @return The semantic filter rule or {@code null} if the syntax is invalid
+     * @see SemanticFilterRuleParser#parse(String)
+     */
+    public static SemanticFilterRule tryParse(String ruleString) {
+        try {
+            return parse(ruleString);
+        } catch (InvalidSyntaxException e) {
+            return null;
+        }
+    }
+
+    /**
+     * Tries parsing a semantic filter rule expression. Returns the {@link SemanticFilterRule} or
+     * {@code null} if the syntax is invalid.
+     * 
+     * @param ruleString
+     *            The semantic filter rule expression
+     * @param ruleName
+     *            The rule name
+     * @return The semantic filter rule or {@code null} if the syntax is invalid
+     * @see SemanticFilterRuleParser#parse(String)
+     */
+    public static SemanticFilterRule tryParse(String ruleString, String ruleName) {
+        try {
+            return parse(ruleString, ruleName);
+        } catch (InvalidSyntaxException e) {
+            return null;
+        }
+    }
+}