Determine SQL parser API (#7954)

* Refactor SQLParserEngine

* Determine SQL parser API

shardingsphere-sql-parser/shardingsphere-sql-parser-engine/src/main/java/org/apache/shardingsphere/sql/parser/api/parser/SQLParserEngineFactory.java → shardingsphere-sql-parser/shardingsphere-sql-parser-engine/src/main/java/org/apache/shardingsphere/sql/parser/api/SQLParserEngine.java

@@ -15,29 +15,56 @@
  * limitations under the License.
  */
 
-package org.apache.shardingsphere.sql.parser.api.parser;
+package org.apache.shardingsphere.sql.parser.api;
 
 import lombok.AccessLevel;
 import lombok.NoArgsConstructor;
+import org.antlr.v4.runtime.tree.ParseTree;
+import org.antlr.v4.runtime.tree.ParseTreeVisitor;
+import org.apache.shardingsphere.sql.parser.core.parser.SQLParserExecutor;
+import org.apache.shardingsphere.sql.parser.core.visitor.SQLVisitorFactory;
+import org.apache.shardingsphere.sql.parser.core.visitor.SQLVisitorRule;
 
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 
 /**
- * SQL parser engine factory.
+ * SQL parser engine.
  */
 @NoArgsConstructor(access = AccessLevel.PRIVATE)
-public final class SQLParserEngineFactory {
+public final class SQLParserEngine {
     
-    private static final Map<String, SQLParserEngine> ENGINES = new ConcurrentHashMap<>();
+    private static final Map<String, SQLParserExecutor> ENGINES = new ConcurrentHashMap<>();
     
     /**
-     * Get SQL parser engine.
+     * Parse SQL.
      *
      * @param databaseType database type
-     * @return SQL parser engine
+     * @param sql SQL to be parsed
+     * @param useCache whether use cache
+     * @param visitorType SQL visitor type
+     * @param <T> type of SQL visitor result
+     * @return SQL visitor result
      */
-    public static SQLParserEngine getSQLParserEngine(final String databaseType) {
+    public static <T> T parse(final String databaseType, final String sql, final boolean useCache, final String visitorType) {
+        ParseTree parseTree = parse(databaseType, sql, useCache);
+        ParseTreeVisitor<T> visitor = SQLVisitorFactory.newInstance(databaseType, visitorType, SQLVisitorRule.valueOf(parseTree.getClass()));
+        return parseTree.accept(visitor);
+    }
+    
+    /**
+     * Parse SQL.
+     *
+     * @param databaseType database type
+     * @param sql SQL to be parsed
+     * @param useCache whether use cache
+     * @return parse tree
+     */
+    public static ParseTree parse(final String databaseType, final String sql, final boolean useCache) {
+        return getSQLParserExecutor(databaseType).parse(sql, useCache);
+    }
+    
+    private static SQLParserExecutor getSQLParserExecutor(final String databaseType) {
         if (ENGINES.containsKey(databaseType)) {
             return ENGINES.get(databaseType);
         }
@@ -45,7 +72,7 @@ public final class SQLParserEngineFactory {
             if (ENGINES.containsKey(databaseType)) {
                 return ENGINES.get(databaseType);
             }
-            SQLParserEngine result = new SQLParserEngine(databaseType);
+            SQLParserExecutor result = new SQLParserExecutor(databaseType);
             ENGINES.put(databaseType, result);
             return result;
         }

shardingsphere-sql-parser/shardingsphere-sql-parser-engine/src/main/java/org/apache/shardingsphere/sql/parser/api/visitor/SQLVisitorEngine.java

-/*
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements.  See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * The ASF licenses this file to You 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.apache.shardingsphere.sql.parser.api.visitor;
-
-import lombok.RequiredArgsConstructor;
-import org.antlr.v4.runtime.tree.ParseTree;
-import org.antlr.v4.runtime.tree.ParseTreeVisitor;
-import org.apache.shardingsphere.sql.parser.core.visitor.SQLVisitorFactory;
-import org.apache.shardingsphere.sql.parser.core.visitor.SQLVisitorRule;
-
-/**
- * SQL visitor engnie.
- * 
- * @param <T> type of return value
- */
-@RequiredArgsConstructor
-public final class SQLVisitorEngine<T> {
-    
-    private final String databaseType;
-    
-    private final String visitorType;
-    
-    /**
-     * Visit parse tree.
-     *
-     * @param parseTree parse tree
-     * @return visit result
-     */
-    public T visit(final ParseTree parseTree) {
-        ParseTreeVisitor<T> visitor = SQLVisitorFactory.newInstance(databaseType, visitorType, SQLVisitorRule.valueOf(parseTree.getClass()));
-        return parseTree.accept(visitor);
-    }
-}

shardingsphere-sql-parser/shardingsphere-sql-parser-engine/src/main/java/org/apache/shardingsphere/sql/parser/api/visitor/SQLVisitorEngineFactory.java

-/*
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements.  See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * The ASF licenses this file to You 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.apache.shardingsphere.sql.parser.api.visitor;
-
-import lombok.AccessLevel;
-import lombok.NoArgsConstructor;
-
-/**
- * SQL visitor engine factory.
- */
-@NoArgsConstructor(access = AccessLevel.PRIVATE)
-public final class SQLVisitorEngineFactory {
-    
-    /**
-     * Get SQL visitor engine.
-     *
-     * @param databaseType database type
-     * @param visitorType visitor type
-     * @param <T> type of visitor result
-     * @return SQL visitor engine
-     */
-    public static <T> SQLVisitorEngine<T> getSQLVisitorEngine(final String databaseType, final String visitorType) {
-        return new SQLVisitorEngine<>(databaseType, visitorType);
-    }
-}

shardingsphere-sql-parser/shardingsphere-sql-parser-engine/src/main/java/org/apache/shardingsphere/sql/parser/api/parser/SQLParserEngine.java → shardingsphere-sql-parser/shardingsphere-sql-parser-engine/src/main/java/org/apache/shardingsphere/sql/parser/core/parser/SQLParserExecutor.java

@@ -15,7 +15,7 @@
  * limitations under the License.
  */
 
-package org.apache.shardingsphere.sql.parser.api.parser;
+package org.apache.shardingsphere.sql.parser.core.parser;
 
 import lombok.RequiredArgsConstructor;
 import org.antlr.v4.runtime.BailErrorStrategy;
@@ -24,18 +24,17 @@ import org.antlr.v4.runtime.atn.PredictionMode;
 import org.antlr.v4.runtime.misc.ParseCancellationException;
 import org.antlr.v4.runtime.tree.ErrorNode;
 import org.antlr.v4.runtime.tree.ParseTree;
+import org.apache.shardingsphere.sql.parser.api.parser.SQLParser;
 import org.apache.shardingsphere.sql.parser.cache.SQLParsedResultCache;
-import org.apache.shardingsphere.sql.parser.core.parser.ParseASTNode;
-import org.apache.shardingsphere.sql.parser.core.parser.SQLParserFactory;
 import org.apache.shardingsphere.sql.parser.exception.SQLParsingException;
 
 import java.util.Optional;
 
 /**
- * SQL parser engine.
+ * SQL parser executor.
  */
 @RequiredArgsConstructor
-public final class SQLParserEngine {
+public final class SQLParserExecutor {
     
     private final String databaseType;
     

shardingsphere-sql-parser/shardingsphere-sql-parser-engine/src/main/java/org/apache/shardingsphere/sql/parser/statement/standard/StandardSQLStatementParserEngine.java

@@ -18,12 +18,8 @@
 package org.apache.shardingsphere.sql.parser.statement.standard;
 
 import lombok.RequiredArgsConstructor;
-import org.antlr.v4.runtime.tree.ParseTree;
-import org.antlr.v4.runtime.tree.ParseTreeVisitor;
+import org.apache.shardingsphere.sql.parser.api.SQLParserEngine;
 import org.apache.shardingsphere.sql.parser.cache.SQLParsedResultCache;
-import org.apache.shardingsphere.sql.parser.core.visitor.SQLVisitorFactory;
-import org.apache.shardingsphere.sql.parser.core.visitor.SQLVisitorRule;
-import org.apache.shardingsphere.sql.parser.api.parser.SQLParserEngineFactory;
 import org.apache.shardingsphere.sql.parser.hook.ParsingHookRegistry;
 import org.apache.shardingsphere.sql.parser.sql.common.statement.SQLStatement;
 import org.apache.shardingsphere.sql.parser.statement.SQLStatementParserEngine;
@@ -65,20 +61,14 @@ public final class StandardSQLStatementParserEngine implements SQLStatementParse
     
     private SQLStatement parse0(final String sql, final boolean useCache) {
         if (!useCache) {
-            return parseSQLStatement(sql);
+            return SQLParserEngine.parse(databaseTypeName, sql, false, "STATEMENT");
         }
         Optional<SQLStatement> statement = cache.get(sql);
         if (statement.isPresent()) {
             return statement.get();
         }
-        SQLStatement result = parseSQLStatement(sql);
+        SQLStatement result = SQLParserEngine.parse(databaseTypeName, sql, false, "STATEMENT");
         cache.put(sql, result);
         return result;
     }
-    
-    private SQLStatement parseSQLStatement(final String sql) {
-        ParseTree parseTree = SQLParserEngineFactory.getSQLParserEngine(databaseTypeName).parse(sql, false);
-        ParseTreeVisitor<SQLStatement> visitor = SQLVisitorFactory.newInstance(databaseTypeName, "STATEMENT", SQLVisitorRule.valueOf(parseTree.getClass()));
-        return parseTree.accept(visitor);
-    }
 }

shardingsphere-sql-parser/shardingsphere-sql-parser-engine/src/test/java/org/apache/shardingsphere/sql/parser/api/SQLParserEngineFactoryTest.java

-/*
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements.  See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * The ASF licenses this file to You 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.apache.shardingsphere.sql.parser.api;
-
-import org.apache.shardingsphere.sql.parser.api.parser.SQLParserEngineFactory;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-
-import java.lang.reflect.Field;
-import java.util.Map;
-
-import static org.hamcrest.CoreMatchers.is;
-import static org.junit.Assert.assertThat;
-
-public final class SQLParserEngineFactoryTest {
-    
-    @Before
-    @After
-    public void reset() throws NoSuchFieldException, IllegalAccessException {
-        Field field = SQLParserEngineFactory.class.getDeclaredField("ENGINES");
-        field.setAccessible(true);
-        ((Map) field.get(SQLParserEngineFactory.class)).clear();
-    }
-    
-    @Test
-    public void assertGetSQLParserEngine() {
-        assertThat(SQLParserEngineFactory.getSQLParserEngine("MySQL"), is(SQLParserEngineFactory.getSQLParserEngine("MySQL")));
-    }
-}