解密陌生人（6）数据库操作工具和文件操作类

提示： 因为工程稍微有点大对我个人来说，所以可能在某些方面讲的不清楚或逻辑性不够强，如果有问题请及时@我。
原工程：https://github.com/LineChen/

在具体介绍各项操作之前先介绍一下数据库操作类和文件操作类。
数据库：MySQL、MVC模式
SqlHelper ：

package com.database;

import java.sql.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class SqlHelper {
String dbuserId = “root”;
String dbuserPassWd = “root”;
String driverName = “com.mysql.jdbc.Driver”;
String url = “jdbc:mysql://localhost:3306/hello_stranger_db”;
PreparedStatement ps = null;
Connection ct = null;
ResultSet rs = null;

// 连接数据库
public boolean ConnectDb() {
    boolean isConected = true;
    try {
        Class.forName(driverName);
        ct = DriverManager.getConnection(url, dbuserId, dbuserPassWd);
    } catch (Exception e) {
        isConected = false;
        e.printStackTrace();
    }
    return isConected;

}

/** 创建数据库或新的表 */
public boolean create(String sql) {
    boolean isOk = true;
    try {
        ConnectDb();
        ps = ct.prepareStatement(sql);
        isOk = !ps.execute();// 返回布尔值,返回false 代表成功,反之失败
    } catch (Exception e) {
        isOk = false;
        e.printStackTrace();
    } finally {
        this.close();
    }
    return isOk;
}


/** 查询 */
public ResultSet query(String sql, String[] paras) {
    try {
        ConnectDb();
        ps = ct.prepareStatement(sql);
        // 对参数赋值
        for (int i = 0; i < paras.length; i++) {
            ps.setString(i + 1, paras[i]);
        }
        rs = ps.executeQuery();
    } catch (Exception e) {
        e.printStackTrace();
    }
    return rs;
}

/** 增删改 */
public boolean updExecute(String sql, String[] paras) {
    boolean b = true;
    try {
        ConnectDb();
        ps = ct.prepareStatement(sql);
        // 给ps的？赋值
        for (int i = 0; i < paras.length; i++) {
            ps.setString(i + 1, paras[i]);
        }
        ps.executeUpdate();// 执行操作 返回变化的行数
        // if (ps.executeUpdate() != 1) {
        // b = false;
        // }
    } catch (Exception e) {
        b = false;
        e.printStackTrace();
    } finally {
        this.close();
    }
    return b;
}

// 统一关闭资源
public void close() {
    try {
        if (rs != null)
            rs.close();
        if (ps != null)
            ps.close();
        if (ct != null)
            ct.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

}

具体业务逻辑，model层，根据需要添加相应的方法，以下包括注册、登录、找回密码、添加好友、保存或获取离线消息等

package com.database;

import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;

import com.alibaba.fastjson.JSONObject;
import com.imomo_msg.MsgDb;
import com.imomo_msg.MsgKeys;
import com.server_utils.FileTools;

public class SqlModel {
/* 新增用户、修改信息等操作 /
public boolean updateDb(String sql, String[] paras) {
// 创建SqlHelper(如果程序并发性不考虑，可以吧SqlHelper做成静态的)
SqlHelper sqlHelper = new SqlHelper();
return sqlHelper.updExecute(sql, paras);
}

/** 登录验证 */
public boolean checkUser(String userEmail, String userPasswd) {
    SqlHelper sp = null;
    boolean isLegal = false;
    try {
        // 阻止SQL语句 和参数列表
        String sql = "select userPasswd from imomo_clients where userEmail = ?";
        String paras[] = { userEmail };
        sp = new SqlHelper();
        ResultSet rs = sp.query(sql, paras);
        if (rs.next()) {
            if (rs.getString(1).equals(userPasswd)) {
                isLegal = true;
            }
        }
    } catch (Exception e) {
        isLegal = false;
        e.printStackTrace();
    } finally {
        sp.close();
    }
    return isLegal;
}

/**
 * 根据Id返回用户名
 * 
 * @param userId
 * @return 返回null表示不存在该用户
 */
public String getUserName(String userEmail, boolean isEmail) {
    SqlHelper sp = null;
    String userName = "null";
    try {
        String sql = null;
        if(isEmail) {
              sql = "select userName from imomo_clients where userEmail = ?";
        } else {
              sql = "select userName from imomo_clients where userId = ?";
        }
        String paras[] = {userEmail};
        sp = new SqlHelper();
        ResultSet rs = sp.query(sql, paras);
        if (rs.next()) {
            userName = rs.getString(1);
        }
    } catch (Exception e) {
        userName = "null";
        e.printStackTrace();
    } finally {
        sp.close();
    }
    return userName;
}

/**
 * 
 * @param userEmail
 *            用户注册邮箱 或用户Id
 * @param isEmail
 *            是邮箱还是用户Id标识 true - 邮箱 false - 用户Id
 * @return
 */
public JSONObject getUserInfo(String userEmail, boolean isEmail) {
    JSONObject userInfo = new JSONObject();
    SqlHelper sp = null;
    String sql = null;
    try {
        if (isEmail) {
            sql = "select userId, userName, userHeadPath, userSex, userBirthday, personSignature, vitalityValue from imomo_clients where userEmail = ?";
        } else {
            sql = "select userId, userName, userHeadPath, userSex, userBirthday, personSignature, vitalityValue from imomo_clients where userId = ?";
        }
        String paras[] = { userEmail };

        sp = new SqlHelper();
        ResultSet rs = sp.query(sql, paras);
        if (rs.next()) {
            userInfo.put(MsgKeys.userId, rs.getString(1));
            userInfo.put(MsgKeys.userName, rs.getString(2));
            userInfo.put(MsgKeys.userHeadPath, rs.getString(3));
            userInfo.put(MsgKeys.userSex, rs.getString(4));
            userInfo.put(MsgKeys.userBirthday, rs.getString(5));
            userInfo.put(MsgKeys.personSignature, rs.getString(6));
            userInfo.put(MsgKeys.vitalityValue, rs.getInt(7));
        }
    } catch (Exception e) {
        userInfo = null;
        e.printStackTrace();
    } finally {
        sp.close();
    }
    return userInfo;
}

/**
 * 判断一个表是否存在
 * 
 * @param userId
 * @return
 */
public boolean isTableExists(String tableName) {
    boolean isExists = true;
    String sql = "SHOW TABLES like ?";
    String paras[] = { tableName };
    SqlHelper sp = null;
    String tempTable = null;
    try {
        sp = new SqlHelper();
        ResultSet rs = sp.query(sql, paras);
        if (!rs.next()) {
            isExists = false;
        }
    } catch (Exception e) {
        isExists = false;
        e.printStackTrace();
    } finally {
        sp.close();
    }
    return isExists;
}

/**
 * 分配Id
 * 
 * @param userEmail
 * @return
 */
public String allocateId() {
    SqlHelper sp = null;
    int newId = 0;
    try {
        String sql = "select allocate_id from allocation_id where flag = ?";
        String paras[] = { "0" };
        sp = new SqlHelper();
        ResultSet rs = sp.query(sql, paras);
        if (rs.next()) {
            newId = rs.getInt(1);
            sp.updExecute(
                    "update allocation_id set flag = ? where flag = ?",
                    new String[] { "1", "0" });
            sp.updExecute("insert into allocation_id values(?,?)",
                    new String[] { (newId + 1) + "", "0" });
        } else {
            return "null";
        }
    } catch (Exception e) {
        e.printStackTrace();
        return "null";
    } finally {
        sp.close();
    }
    return newId + "";
}

/**
 * 插入一条离线消息
 * 
 * @param msgDb
 * @return
 */
public boolean insertCacheMsg(MsgDb msgDb, String userId) {
    String sql = "insert into " + "mc_" + userId + " values (?,?)";
    String[] paras = { msgDb.msgType + "", msgDb.msgJson };
    return updateDb(sql, paras);
}

/** 根据表名，清空表中的信息缓存 */
public boolean clearMsgCache(String userId) {
    String sql = "delete from " + "mc_" + userId + " where 1 = ?";
    String[] paras = { "1" };
    SqlHelper sqlHelper = new SqlHelper();
    return sqlHelper.updExecute(sql, paras);
}

/**
 * 创建用户消息缓冲表（当接收消息的用户未上线，暂存消息，上线之后立即发送）
 * 
 * @param userId
 *            接收信息的用户Id
 * @return 返回true表示成功，反之失败
 */
public boolean createCacheTable(String userId) {
    String tableName = "mc_" + userId;// 表明尽量短
    String sql = "create table " + tableName
            + " (msgType int(4), msgJson text)";
    SqlHelper sqlHelper = new SqlHelper();
    return sqlHelper.create(sql);
}

/**
 * 得到离线消息记录数
 * 
 * @param userId
 * @return
 */
public int getMsgCount(String userId) {
    int count = 0;// "SELECT count(*) FROM sqlite_master WHERE type=‘table‘ AND name= ? ";
    String tableName = "mc_" + userId;
    String sql = "select count(*) from " + tableName + " where 1 = ?";
    String paras[] = { "1" };
    SqlHelper sp = null;
    try {
        sp = new SqlHelper();
        ResultSet rs = sp.query(sql, paras);
        if (rs.next()) {
            count = rs.getInt(1);
        }
    } catch (Exception e) {
        count = 0;
        e.printStackTrace();
    } finally {
        sp.close();
    }
    return count;
}

/**
 * 从数据库得到离线消息list
 * 
 * @param userId
 * @return
 */
public List<MsgDb> getCacheMsgs(String userId) {
    String tableName = "mc_" + userId;
    List<MsgDb> list = new ArrayList<MsgDb>();
    String sql = "select * from " + tableName + " where 1 = ?";
    String paras[] = { "1" };
    SqlHelper sp = null;
    try {
        sp = new SqlHelper();
        ResultSet rs = sp.query(sql, paras);
        while (rs.next()) {
            MsgDb msgDb = new MsgDb();
            msgDb.msgType = rs.getInt("msgType");
            msgDb.msgJson = rs.getString("msgJson");
            list.add(msgDb);
        }
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        sp.close();
    }

    return list;
}

/**
 * 添加好友
 * 
 * @param userId
 *            用户Id
 * @param friendId
 *            待添加的好友Id
 * @return
 */
public boolean addFriend(String userId, String friendId) {
    SqlHelper sp = null;
    String sql2 = "select userId from friend_list  where userId = ?";
    String[] pp = { userId };
    try {
        sp = new SqlHelper();
        ResultSet rs = sp.query(sql2, pp);
        if (!rs.next()) {
            System.out.println("rs.next() " + rs.next());
            String sql3 = "insert into friend_list(userId) values(?)";
            String paras[] = { userId };
            updateDb(sql3, paras);
        }
        String sql1 = "select friendList from friend_list  where userId = ?";
        String paras1[] = { userId };
        String freindListStr = "";
        sp = new SqlHelper();
        ResultSet rs2 = sp.query(sql1, paras1);
        if (rs2.next()) {
            freindListStr = rs2.getString(1);
        }
        if (freindListStr == null) {
            freindListStr = friendId;
        } else {
            String[] friends = getFriendIds(userId);
            boolean isExists = false;
            for (String string : friends) {
                if (string.equals(friendId)) {
                    isExists = true;
                    break;
                }
            }
            if (!isExists)
                freindListStr += "," + friendId;
        }

        String sql = "update friend_list set friendList = ? where userId = ?";
        String paras[] = { freindListStr, userId };
        return updateDb(sql, paras);
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        sp.close();
    }
    return false;

}

/**
 * 删除好友
 * 
 * @param userId
 * @param friendId
 * @return
 */
public boolean deleteFriend(String userId, String friendId) {
    String[] oldFriend = this.getFriendIds(userId);
    String newFriendStr = "";
    for (String str : oldFriend) {
        if (!str.equals(friendId)) {
            newFriendStr += str + ",";
        }
    }
    String sql = "update friend_list set friendList = ? where userId = ?";
    String paras[] = { newFriendStr.substring(0, newFriendStr.length() - 1), userId };
    return updateDb(sql, paras);
}

/**
 * 获取好友列表
 * 
 * @param userId
 * @return list
 */
public String[] getFriendIds(String userId) {
    String[] friendList = null;
    String sql = "select friendList from friend_list  where userId = ?";
    String paras[] = { userId };
    SqlHelper sp = null;
    try {
        sp = new SqlHelper();
        ResultSet rs = sp.query(sql, paras);
        if (rs.next()) {
            friendList = rs.getString(1).split(",");
        }
    } catch (Exception e) {

// e.printStackTrace();
} finally {
sp.close();
}
return friendList;
}

/**
 * 更新活力值
 * @param userId
 * @param type
 * @return
 */
public boolean UpdateVitality(String userId, int type){
    SqlHelper sp = null;
    try {
        String sql1 = "select vitalityValue from imomo_clients where userId = ?";
        String[] paras1 = {userId};
        sp = new SqlHelper();
        ResultSet rs = sp.query(sql1, paras1);
        int vitalityValue = 0;
        if (rs.next()) {
            vitalityValue = rs.getInt(1);
        }
        String sql = "update imomo_clients set vitalityValue = ? where userId = ?";
        String[] paras = new String[2];
        if(type == -1){
            paras[0]= (vitalityValue - 10) + "";
        } else if(type == 1){
            paras[0]= (vitalityValue + 15) + "";
        }
        paras[1]=userId;
        return sp.updExecute(sql, paras);
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        sp.close();
    }
    return false;
}

}

文件操作类： 主要的方法是保存二进制文件、获取图片或语音的字节数组
package com.server_utils;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;

import com.imomo_server.ServerUtils;

/**
* 考虑并发性,
*
* @author Administrator
*
*/
public class FileTools {
static FileTools fileTools;

public static void main(String[] args) {
    byte[] fff = FileTools.getInstance().getMultyFileBytes(
            StaticValues.MSG_CACHE_IMA_P_PATH + "fff.png");
    FileTools.getInstance().saveMultyFile(
            StaticValues.MSG_CACHE_IMA_P_PATH + "90joj.jpg", fff);
}

public static FileTools getInstance() {
    // if(fileTools == null){
    // fileTools = new FileTools();
    // }
    return new FileTools();
}

/**
 * @category 存储用户图片或语音消息
 * @param msgBytes
 *            图片或语音byte数组
 */
public void saveMultyFile(String filepath, byte[] msgBytes) {
    if (msgBytes.length > 0) {
        File file = new File(filepath);
        FileOutputStream fileout = null;
        FileChannel fc = null;
        try {
            fileout = new FileOutputStream(file);
            fc = fileout.getChannel();
            fileout.write(msgBytes);
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                fc.close();
                fileout.close();
            } catch (Exception e2) {
                e2.printStackTrace();
            }
        }
    } else {
        System.out.println("警告：文件为空，无法保存!!");
    }
}

/**
 * @param filepath
 *            文件路径
 * @return 图片或语音byte数组
 */
public byte[] getMultyFileBytes(String filepath) {
    File file = new File(filepath);
    ByteBuffer bytebuffer = null;
    FileInputStream fileInputStream = null;
    FileChannel channel = null;
    try {
        if (!file.exists()) {
            System.err.println("该文件不存在...");
        } else {
            fileInputStream = new FileInputStream(file);
            channel = fileInputStream.getChannel();
            bytebuffer = ByteBuffer.allocate((int) channel.size());
            bytebuffer.clear();
            channel.read(bytebuffer);
            return bytebuffer.array();
        }
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            channel.close();
            fileInputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    return null;
}

/**
 * 删除文件
 * 
 * @param filePath
 *            文件路径
 */
public void deleteFile(String filePath) {
    File file = new File(filePath);
    if (file.exists()) {
        file.delete();
    }
}

/**
 * 保存用户反馈信息
 * 
 * @param userId
 * @param reback
 */
public void saveReback(String userId, String reback) {
    File file = new File(StaticValues.REBACK_PATH);
    BufferedWriter out = null;
    if (!file.exists()) {
        try {
            file.createNewFile();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    try {
        out = new BufferedWriter(new OutputStreamWriter(
                new FileOutputStream(file, true)));
        out.write(userId + ":" + reback );//+ "\r\n\r\n"
        out.write("\r\n");
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            out.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

}