decouple find RemoveAvailable with SQLStatement (#4370)

shardingsphere-sql-parser/shardingsphere-sql-parser-engine/src/main/java/org/apache/shardingsphere/sql/parser/sql/statement/dal/dialect/mysql/ShowColumnsStatement.java

@@ -17,8 +17,10 @@
 
 package org.apache.shardingsphere.sql.parser.sql.statement.dal.dialect.mysql;
 
+import com.google.common.base.Optional;
 import lombok.Getter;
 import lombok.Setter;
+import org.apache.shardingsphere.sql.parser.sql.segment.generic.RemoveAvailable;
 import org.apache.shardingsphere.sql.parser.sql.segment.generic.TableSegment;
 import org.apache.shardingsphere.sql.parser.sql.statement.dal.DALStatement;
 import org.apache.shardingsphere.sql.parser.sql.statement.generic.TableSegmentAvailable;
@@ -26,9 +28,20 @@ import org.apache.shardingsphere.sql.parser.sql.statement.generic.TableSegmentAv
 /**
  * Show columns statement.
  */
-@Setter
 @Getter
+@Setter
 public final class ShowColumnsStatement extends DALStatement implements TableSegmentAvailable {
     
     private TableSegment table;
+    
+    private RemoveAvailable fromSchema;
+    
+    /**
+     * Get from schema.
+     *
+     * @return from schema
+     */
+    public Optional<RemoveAvailable> getFromSchema() {
+        return Optional.fromNullable(fromSchema);
+    }
 }

shardingsphere-sql-parser/shardingsphere-sql-parser-engine/src/main/java/org/apache/shardingsphere/sql/parser/sql/statement/dal/dialect/mysql/ShowTableStatusStatement.java

@@ -17,10 +17,25 @@
 
 package org.apache.shardingsphere.sql.parser.sql.statement.dal.dialect.mysql;
 
+import com.google.common.base.Optional;
+import lombok.Setter;
+import org.apache.shardingsphere.sql.parser.sql.segment.generic.RemoveAvailable;
 import org.apache.shardingsphere.sql.parser.sql.statement.dal.DALStatement;
 
 /**
  * Show table status statement.
  */
+@Setter
 public final class ShowTableStatusStatement extends DALStatement {
+    
+    private RemoveAvailable fromSchema;
+    
+    /**
+     * Get from schema.
+     *
+     * @return from schema
+     */
+    public Optional<RemoveAvailable> getFromSchema() {
+        return Optional.fromNullable(fromSchema);
+    }
 }

shardingsphere-sql-parser/shardingsphere-sql-parser-engine/src/main/java/org/apache/shardingsphere/sql/parser/sql/statement/dal/dialect/mysql/ShowTablesStatement.java

@@ -17,10 +17,25 @@
 
 package org.apache.shardingsphere.sql.parser.sql.statement.dal.dialect.mysql;
 
+import com.google.common.base.Optional;
+import lombok.Setter;
+import org.apache.shardingsphere.sql.parser.sql.segment.generic.RemoveAvailable;
 import org.apache.shardingsphere.sql.parser.sql.statement.dal.DALStatement;
 
 /**
  * Show tables statement.
  */
+@Setter
 public final class ShowTablesStatement extends DALStatement {
+    
+    private RemoveAvailable fromSchema;
+    
+    /**
+     * Get from schema.
+     * 
+     * @return from schema
+     */
+    public Optional<RemoveAvailable> getFromSchema() {
+        return Optional.fromNullable(fromSchema);
+    }
 }

shardingsphere-sql-parser/shardingsphere-sql-parser-mysql/src/main/java/org/apache/shardingsphere/sql/parser/core/filler/dal/FromSchemaFiller.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.core.filler.dal;
+
+import org.apache.shardingsphere.sql.parser.core.filler.SQLSegmentFiller;
+import org.apache.shardingsphere.sql.parser.sql.segment.dal.FromSchemaSegment;
+import org.apache.shardingsphere.sql.parser.sql.statement.SQLStatement;
+import org.apache.shardingsphere.sql.parser.sql.statement.dal.dialect.mysql.ShowColumnsStatement;
+import org.apache.shardingsphere.sql.parser.sql.statement.dal.dialect.mysql.ShowTableStatusStatement;
+import org.apache.shardingsphere.sql.parser.sql.statement.dal.dialect.mysql.ShowTablesStatement;
+
+/**
+ * From schema filler.
+ */
+public final class FromSchemaFiller implements SQLSegmentFiller<FromSchemaSegment> {
+    
+    @Override
+    public void fill(final FromSchemaSegment sqlSegment, final SQLStatement sqlStatement) {
+        if (sqlStatement instanceof ShowTablesStatement) {
+            ((ShowTablesStatement) sqlStatement).setFromSchema(sqlSegment);
+        }
+        if (sqlStatement instanceof ShowTableStatusStatement) {
+            ((ShowTableStatusStatement) sqlStatement).setFromSchema(sqlSegment);
+        }
+        if (sqlStatement instanceof ShowColumnsStatement) {
+            ((ShowColumnsStatement) sqlStatement).setFromSchema(sqlSegment);
+        }
+    }
+}

shardingsphere-sql-parser/shardingsphere-sql-parser-mysql/src/main/java/org/apache/shardingsphere/sql/parser/visitor/impl/MySQLDALVisitor.java

@@ -89,6 +89,7 @@ public final class MySQLDALVisitor extends MySQLVisitor {
         if (null != ctx.fromSchema()) {
             FromSchemaSegment fromSchemaSegment = (FromSchemaSegment) visit(ctx.fromSchema());
             result.getAllSQLSegments().add(fromSchemaSegment);
+            result.setFromSchema(fromSchemaSegment);
         }
         if (null != ctx.showLike()) {
             ShowLikeSegment showLikeSegment = (ShowLikeSegment) visit(ctx.showLike());
@@ -103,6 +104,7 @@ public final class MySQLDALVisitor extends MySQLVisitor {
         if (null != ctx.fromSchema()) {
             FromSchemaSegment fromSchemaSegment = (FromSchemaSegment) visit(ctx.fromSchema());
             result.getAllSQLSegments().add(fromSchemaSegment);
+            result.setFromSchema(fromSchemaSegment);
         }
         if (null != ctx.showLike()) {
             ShowLikeSegment showLikeSegment = (ShowLikeSegment) visit(ctx.showLike());
@@ -123,6 +125,7 @@ public final class MySQLDALVisitor extends MySQLVisitor {
         if (null != ctx.fromSchema()) {
             FromSchemaSegment fromSchemaSegment = (FromSchemaSegment) visit(ctx.fromSchema());
             result.getAllSQLSegments().add(fromSchemaSegment);
+            result.setFromSchema(fromSchemaSegment);
         }
         return result;
     }

shardingsphere-sql-parser/shardingsphere-sql-parser-mysql/src/main/resources/META-INF/parsing-rule-definition/mysql/filler-rule-definition.xml

@@ -18,4 +18,5 @@
 
 <filler-rule-definition>
     <filler-rule sql-segment-class="org.apache.shardingsphere.sql.parser.sql.segment.tcl.AutoCommitSegment" filler-class="org.apache.shardingsphere.sql.parser.core.filler.tcl.MySQLAutoCommitFiller" />
+    <filler-rule sql-segment-class="org.apache.shardingsphere.sql.parser.sql.segment.dal.FromSchemaSegment" filler-class="org.apache.shardingsphere.sql.parser.core.filler.dal.FromSchemaFiller" />
 </filler-rule-definition>

shardingsphere-underlying/shardingsphere-rewrite/shardingsphere-rewrite-engine/src/main/java/org/apache/shardingsphere/underlying/rewrite/sql/token/generator/generic/RemoveTokenGenerator.java

@@ -17,14 +17,17 @@
 
 package org.apache.shardingsphere.underlying.rewrite.sql.token.generator.generic;
 
+import com.google.common.base.Preconditions;
 import org.apache.shardingsphere.sql.parser.relation.statement.SQLStatementContext;
-import org.apache.shardingsphere.sql.parser.sql.segment.SQLSegment;
 import org.apache.shardingsphere.sql.parser.sql.segment.generic.RemoveAvailable;
+import org.apache.shardingsphere.sql.parser.sql.statement.dal.dialect.mysql.ShowColumnsStatement;
+import org.apache.shardingsphere.sql.parser.sql.statement.dal.dialect.mysql.ShowTableStatusStatement;
+import org.apache.shardingsphere.sql.parser.sql.statement.dal.dialect.mysql.ShowTablesStatement;
 import org.apache.shardingsphere.underlying.rewrite.sql.token.generator.CollectionSQLTokenGenerator;
 import org.apache.shardingsphere.underlying.rewrite.sql.token.pojo.generic.RemoveToken;
 
 import java.util.Collection;
-import java.util.LinkedList;
+import java.util.Collections;
 
 /**
  * Remove token generator.
@@ -33,15 +36,35 @@ public final class RemoveTokenGenerator implements CollectionSQLTokenGenerator {
     
     @Override
     public boolean isGenerateSQLToken(final SQLStatementContext sqlStatementContext) {
-        return !sqlStatementContext.getSqlStatement().findSQLSegments(RemoveAvailable.class).isEmpty();
+        if (sqlStatementContext.getSqlStatement() instanceof ShowTablesStatement) {
+            return ((ShowTablesStatement) sqlStatementContext.getSqlStatement()).getFromSchema().isPresent();
+        }
+        if (sqlStatementContext.getSqlStatement() instanceof ShowTableStatusStatement) {
+            return ((ShowTableStatusStatement) sqlStatementContext.getSqlStatement()).getFromSchema().isPresent();
+        }
+        if (sqlStatementContext.getSqlStatement() instanceof ShowColumnsStatement) {
+            return ((ShowColumnsStatement) sqlStatementContext.getSqlStatement()).getFromSchema().isPresent();
+        }
+        return false;
     }
     
     @Override
     public Collection<RemoveToken> generateSQLTokens(final SQLStatementContext sqlStatementContext) {
-        Collection<RemoveToken> result = new LinkedList<>();
-        for (SQLSegment each : sqlStatementContext.getSqlStatement().findSQLSegments(RemoveAvailable.class)) {
-            result.add(new RemoveToken(each.getStartIndex(), each.getStopIndex()));
+        if (sqlStatementContext.getSqlStatement() instanceof ShowTablesStatement) {
+            Preconditions.checkState(((ShowTablesStatement) sqlStatementContext.getSqlStatement()).getFromSchema().isPresent());
+            RemoveAvailable removeAvailable = ((ShowTablesStatement) sqlStatementContext.getSqlStatement()).getFromSchema().get();
+            return Collections.singletonList(new RemoveToken(removeAvailable.getStartIndex(), removeAvailable.getStopIndex()));
+        }
+        if (sqlStatementContext.getSqlStatement() instanceof ShowTableStatusStatement) {
+            Preconditions.checkState(((ShowTableStatusStatement) sqlStatementContext.getSqlStatement()).getFromSchema().isPresent());
+            RemoveAvailable removeAvailable = ((ShowTableStatusStatement) sqlStatementContext.getSqlStatement()).getFromSchema().get();
+            return Collections.singletonList(new RemoveToken(removeAvailable.getStartIndex(), removeAvailable.getStopIndex()));
+        }
+        if (sqlStatementContext.getSqlStatement() instanceof ShowColumnsStatement) {
+            Preconditions.checkState(((ShowColumnsStatement) sqlStatementContext.getSqlStatement()).getFromSchema().isPresent());
+            RemoveAvailable removeAvailable = ((ShowColumnsStatement) sqlStatementContext.getSqlStatement()).getFromSchema().get();
+            return Collections.singletonList(new RemoveToken(removeAvailable.getStartIndex(), removeAvailable.getStopIndex()));
         }
-        return result;
+        return Collections.emptyList();
     }
 }