/*
* Copyright 2014 mango.concurrent.cc
*
* The Mango Project 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 cc.concurrent.mango.runtime.operator;
import cc.concurrent.mango.SQL;
import cc.concurrent.mango.exception.IncorrectAnnotationException;
import cc.concurrent.mango.exception.IncorrectReturnTypeException;
import cc.concurrent.mango.exception.IncorrectSqlException;
import cc.concurrent.mango.runtime.parser.ASTRootNode;
import cc.concurrent.mango.runtime.parser.Parser;
import cc.concurrent.mango.util.Strings;
import java.lang.reflect.Method;
import java.util.regex.Pattern;
/**
* Operator工厂
*
* @author ash
*/
public class OperatorFactory {
private final static Pattern INSERT_PATTERN = Pattern.compile("^\\s*INSERT\\s+", Pattern.CASE_INSENSITIVE);
private final static Pattern DELETE_PATTERN = Pattern.compile("^\\s*DELETE\\s+", Pattern.CASE_INSENSITIVE);
private final static Pattern UPDATE_PATTERN = Pattern.compile("^\\s*UPDATE\\s+", Pattern.CASE_INSENSITIVE);
private final static Pattern SELECT_PATTERN = Pattern.compile("^\\s*SELECT\\s+", Pattern.CASE_INSENSITIVE);
/**
* 获取Operator
*
* @param method
* @return
* @throws Exception
*/
public static CacheableOperator getOperator(Method method) throws Exception {
SQL sqlAnno = method.getAnnotation(SQL.class);
if (sqlAnno == null) {
throw new IncorrectAnnotationException("each method expected one cc.concurrent.mango.SQL annotation " +
"but not found");
}
String sql = sqlAnno.value();
if (Strings.isNullOrEmpty(sql)) {
throw new IncorrectSqlException("sql is null or empty");
}
ASTRootNode rootNode = new Parser(sql).parse().reduce();
SQLType sqlType = getSQLType(sql);
Class<?> returnType = method.getReturnType();
if (sqlType == SQLType.SELECT) { // 查
return new QueryOperator(rootNode, method, sqlType);
} else if (int.class.equals(returnType) || long.class.equals(returnType)) { // 更新
return new UpdateOperator(rootNode, method, sqlType);
} else if (int[].class.equals(returnType)) { // 批量更新
return new BatchUpdateOperator(rootNode, method, sqlType);
} else {
throw new IncorrectReturnTypeException("if sql don't start with select, " +
"update return type expected int, " +
"batch update return type expected int[], " +
"but " + method.getReturnType());
}
}
private static SQLType getSQLType(String sql) {
if (INSERT_PATTERN.matcher(sql).find()) {
return SQLType.INSERT;
} else if (DELETE_PATTERN.matcher(sql).find()) {
return SQLType.DELETE;
} else if (UPDATE_PATTERN.matcher(sql).find()) {
return SQLType.UPDATE;
} else if (SELECT_PATTERN.matcher(sql).find()) {
return SQLType.SELECT;
} else {
throw new IncorrectSqlException("sql must start with INSERT or DELETE or UPDATE or SELECT");
}
}
}