SelectSqlOperation.java

/*
 * Copyright 2008 Pavel Syrtsov
 *
 * Licensed 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 com.sf.ddao.ops;

import com.sf.ddao.DaoException;
import com.sf.ddao.Select;
import com.sf.ddao.chain.CtxHelper;
import com.sf.ddao.chain.InitializerException;
import com.sf.ddao.chain.Intializible;
import com.sf.ddao.chain.MethodCallCtx;
import com.sf.ddao.factory.StatementFactory;
import com.sf.ddao.factory.StatementFactoryException;
import com.sf.ddao.orm.RSMapper;
import com.sf.ddao.orm.RSMapperFactory;
import com.sf.ddao.orm.RSMapperFactoryRegistry;
import org.apache.commons.chain.Command;
import org.apache.commons.chain.Context;

import javax.inject.Inject;
import java.lang.annotation.Annotation;
import java.lang.reflect.AnnotatedElement;
import java.lang.reflect.Method;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

/**
 * Created by: Pavel Syrtsov
 * Date: Apr 2, 2007
 * Time: 8:10:29 PM
 */
public class SelectSqlOperation implements Command, Intializible {
    @Inject
    private StatementFactory statementFactory;
    private RSMapperFactory rsMapperFactory;

    public boolean execute(Context context) throws Exception {
        final MethodCallCtx callCtx = CtxHelper.get(context, MethodCallCtx.class);
        try {
            final Object res = exec(context, callCtx.getArgs());
            callCtx.setLastReturn(res);
            return CONTINUE_PROCESSING;
        } catch (Exception t) {
            throw new DaoException("Failed to execute sql operation for " + callCtx.getMethod(), t);
        }
    }

    public Object exec(Context context, Object[] args) throws StatementFactoryException, SQLException {
        PreparedStatement preparedStatement = statementFactory.createStatement(context, false);
        ResultSet resultSet = preparedStatement.executeQuery();
        RSMapper RSMapper = rsMapperFactory.getInstance(args, resultSet);
        final Object res = RSMapper.handle(context, resultSet);
        resultSet.close();
        preparedStatement.close();
        return res;
    }

    public void init(AnnotatedElement element, String sql) {
        try {
            statementFactory.init(element, sql);
            rsMapperFactory = RSMapperFactoryRegistry.create((Method) element);
        } catch (Exception e) {
            throw new InitializerException("Failed to initialize sql operation for " + element, e);
        }
    }

    public void init(AnnotatedElement element, Annotation annotation) {
        Select selectSql = element.getAnnotation(Select.class);
        init(element, selectSql.value());
    }
}