add InsertSetAddGeneratedKeyTokenGenerator

sharding-core/sharding-core-rewrite/src/main/java/org/apache/shardingsphere/core/rewrite/token/generator/InsertSetAddGeneratedKeyTokenGenerator.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.core.rewrite.token.generator;
+
+import com.google.common.base.Optional;
+import org.apache.shardingsphere.core.parse.sql.segment.dml.assignment.AssignmentSegment;
+import org.apache.shardingsphere.core.parse.sql.segment.dml.assignment.SetAssignmentsSegment;
+import org.apache.shardingsphere.core.parse.sql.statement.SQLStatement;
+import org.apache.shardingsphere.core.parse.sql.statement.dml.InsertStatement;
+import org.apache.shardingsphere.core.parse.sql.token.impl.InsertSetAddGeneratedKeyToken;
+import org.apache.shardingsphere.core.rule.ShardingRule;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Insert set add items token generator.
+ *
+ * @author panjuan
+ */
+public final class InsertSetAddGeneratedKeyTokenGenerator implements OptionalSQLTokenGenerator<ShardingRule> {
+    
+    @Override
+    public Optional<InsertSetAddGeneratedKeyToken> generateSQLToken(final SQLStatement sqlStatement, final ShardingRule shardingRule) {
+        Optional<SetAssignmentsSegment> setAssignmentsSegment = sqlStatement.findSQLSegment(SetAssignmentsSegment.class);
+        if (!(sqlStatement instanceof InsertStatement && setAssignmentsSegment.isPresent())) {
+            return Optional.absent();
+        }
+        return createInsertSetAddGeneratedKeyToken((InsertStatement) sqlStatement, shardingRule, setAssignmentsSegment.get());
+    }
+    
+    private Optional<InsertSetAddGeneratedKeyToken> createInsertSetAddGeneratedKeyToken(final InsertStatement insertStatement, final ShardingRule shardingRule, final SetAssignmentsSegment segment) {
+        Optional<String> generatedKeyColumn = getGeneratedKeyColumn(insertStatement, shardingRule);
+        if (generatedKeyColumn.isPresent()) {
+            List<AssignmentSegment> assignments = new ArrayList<>(segment.getAssignments());
+            return Optional.of(new InsertSetAddGeneratedKeyToken(assignments.get(assignments.size() - 1).getStopIndex() + 1, generatedKeyColumn.get()));
+        }
+        return Optional.absent();
+    }
+    
+    private Optional<String> getGeneratedKeyColumn(final InsertStatement insertStatement, final ShardingRule shardingRule) {
+        String tableName = insertStatement.getTables().getSingleTableName();
+        Optional<String> generateKeyColumn = shardingRule.findGenerateKeyColumnName(tableName);
+        return generateKeyColumn.isPresent() && !insertStatement.getColumnNames().contains(generateKeyColumn.get()) ? generateKeyColumn : Optional.<String>absent();
+    }
+}