jdbcutil.java

来自「用jbuilder写的源程序」· Java 代码 · 共 116 行

/*
 * Copyright 2003-2006 the original author or authors.
 * 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.jdon.model.query;

import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import org.apache.log4j.Logger;

/**
 * @author <a href="mailto:[e-mail]">banq </a>
 *  
 */
public class JdbcUtil {
    private final static Logger logger = Logger.getLogger(JdbcUtil.class);

    /**
     * queryParam type only support String Integer Float or Long Double Bye Short
     * if you need operate other types, you must use JDBC directly!
     */
    public void setQueryParams(Collection queryParams, PreparedStatement ps) throws Exception {
        if ((queryParams == null) || (queryParams.size() == 0))
            return;
        int i = 1;
        Object key = null;

        Iterator iter = queryParams.iterator();
        while (iter.hasNext()) {
            key = iter.next();
            if (key != null) {
                convertType(i, key, ps);
                logger.debug("[JdonFramework] parameter " + i + " = " + key.toString());
            } else {
                logger.warn("[JdonFramework] parameter " + i + " is null");
                ps.setString(i, "");
            }
            i++;
        }

    }

    private void convertType(int i, Object key, PreparedStatement ps) {
        try {
            if (key instanceof java.lang.String) {
                String keyStrs = (String) key;
                ps.setString(i, keyStrs);
            } else if (key instanceof Integer) {
                ps.setInt(i, ((Integer) key).intValue());
            } else if (key instanceof Float) {
                ps.setFloat(i, ((Float) key).floatValue());
            } else if (key instanceof Long) {
                ps.setLong(i, ((Long) key).longValue());
            } else if (key instanceof Double) {
                ps.setDouble(i, ((Double) key).doubleValue());
            } else if (key instanceof Byte) {
                ps.setByte(i, ((Byte) key).byteValue());
            } else if (key instanceof Short) {
                ps.setShort(i, ((Short) key).shortValue());
            } else {
                ps.setObject(i, key);
                logger.debug("[JdonFramework]warniing: Type =" + key.getClass().getName() + " isn't be converted!");
            }
        } catch (SQLException e) {
            logger.error("[JdonFramework]setQueryParams error " + e + "in parameter order=" + i + " its value=" + key);
        } catch (Exception e) {
            logger.error(e);
        }
    }

    /**
     * return a List
     * in the List, every object is a map,  
     * by database column name, we can get the its result from map
     * 
     * 
     * @param rs ResultSet
     * @return List
     * @throws Exception
     */
    public List extract(ResultSet rs) throws Exception {
        ResultSetMetaData meta = rs.getMetaData();
        int count = meta.getColumnCount();
        List ret = new ArrayList();
        while (rs.next()) {
            Map map = new LinkedHashMap(count);
            for (int i = 1; i <= count; i++) {
                map.put(meta.getColumnName(i), rs.getObject(i));
            }
            ret.add(map);
        }
        return ret;
    }

}