tdscore.java

jtds的源码 是你学习java的好东西

// jTDS JDBC Driver for Microsoft SQL Server and Sybase
// Copyright (C) 2004 The jTDS Project
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
//
package net.sourceforge.jtds.jdbc;

import java.io.*;
import java.sql.*;
import java.util.Arrays;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Random;

import net.sourceforge.jtds.ssl.*;
import net.sourceforge.jtds.util.*;

/**
 * This class implements the Sybase / Microsoft TDS protocol.
 * <p>
 * Implementation notes:
 * <ol>
 * <li>This class, together with TdsData, encapsulates all of the TDS specific logic
 *     required by the driver.
 * <li>This is a ground up reimplementation of the TDS protocol and is rather
 *     simpler, and hopefully easier to understand, than the original.
 * <li>The layout of the various Login packets is derived from the original code
 *     and freeTds work, and incorporates changes including the ability to login as a TDS 5.0 user.
 * <li>All network I/O errors are trapped here, reported to the log (if active)
 *     and the parent Connection object is notified that the connection should be considered
 *     closed.
 * <li>Rather than having a large number of classes one for each token, useful information
 *     about the current token is gathered together in the inner TdsToken class.
 * <li>As the rest of the driver interfaces to this code via higher-level method calls there
 *     should be know need for knowledge of the TDS protocol to leak out of this class.
 *     It is for this reason that all the TDS Token constants are private.
 * </ol>
 *
 * @author Mike Hutchinson
 * @author Matt Brinkley
 * @author Alin Sinpalean
 * @author FreeTDS project
 * @version $Id: TdsCore.java,v 1.115 2007/07/08 17:28:23 bheineman Exp $
 */
public class TdsCore {
    /**
     * Inner static class used to hold information about TDS tokens read.
     */
    private static class TdsToken {
        /** The current TDS token byte. */
        byte token;
        /** The status field from a DONE packet. */
        byte status;
        /** The operation field from a DONE packet. */
        byte operation;
        /** The update count from a DONE packet. */
        int updateCount;
        /** The nonce from an NTLM challenge packet. */
        byte[] nonce;
        /** NTLM authentication message. */
        byte[] ntlmMessage;
        /** target info for NTLM message TODO: I don't need to store these!!! */
        byte[] ntlmTarget;
        /** The dynamic parameters from the last TDS_DYNAMIC token. */
        ColInfo[] dynamParamInfo;
        /** The dynamic parameter data from the last TDS_DYNAMIC token. */
        Object[] dynamParamData;

        /**
         * Retrieve the update count status.
         *
         * @return <code>boolean</code> true if the update count is valid.
         */
        boolean isUpdateCount() {
            return (token == TDS_DONE_TOKEN || token == TDS_DONEINPROC_TOKEN)
                    && (status & DONE_ROW_COUNT) != 0;
        }

        /**
         * Retrieve the DONE token status.
         *
         * @return <code>boolean</code> true if the current token is a DONE packet.
         */
        boolean isEndToken() {
            return token == TDS_DONE_TOKEN
                   || token == TDS_DONEINPROC_TOKEN
                   || token == TDS_DONEPROC_TOKEN;
        }

        /**
         * Retrieve the NTLM challenge status.
         *
         * @return <code>boolean</code> true if the current token is an NTLM challenge.
         */
        boolean isAuthToken() {
            return token == TDS_AUTH_TOKEN;
        }

        /**
         * Retrieve the results pending status.
         *
         * @return <code>boolean</code> true if more results in input.
         */
        boolean resultsPending() {
            return !isEndToken() || ((status & DONE_MORE_RESULTS) != 0);
        }

        /**
         * Retrieve the result set status.
         *
         * @return <code>boolean</code> true if the current token is a result set.
         */
        boolean isResultSet() {
            return token == TDS_COLFMT_TOKEN
                   || token == TDS7_RESULT_TOKEN
                   || token == TDS_RESULT_TOKEN
                   || token == TDS5_WIDE_RESULT
                   || token == TDS_COLINFO_TOKEN
                   || token == TDS_ROW_TOKEN;
        }

        /**
         * Retrieve the row data status.
         *
         * @return <code>boolean</code> true if the current token is a result row.
         */
        public boolean isRowData() {
            return token == TDS_ROW_TOKEN;
        }

    }
    /**
     * Inner static class used to hold table meta data.
     */
    private static class TableMetaData {
        /** Table catalog (database) name. */
        String catalog;
        /** Table schema (user) name. */
        String schema;
        /** Table name. */
        String name;
    }

    //
    // Package private constants
    //
    /** Minimum network packet size. */
    public static final int MIN_PKT_SIZE = 512;
    /** Default minimum network packet size for TDS 7.0 and newer. */
    public static final int DEFAULT_MIN_PKT_SIZE_TDS70 = 4096;
    /** Maximum network packet size. */
    public static final int MAX_PKT_SIZE = 32768;
    /** The size of the packet header. */
    public static final int PKT_HDR_LEN = 8;
    /** TDS 4.2 or 7.0 Query packet. */
    public static final byte QUERY_PKT = 1;
    /** TDS 4.2 or 5.0 Login packet. */
    public static final byte LOGIN_PKT = 2;
    /** TDS Remote Procedure Call. */
    public static final byte RPC_PKT = 3;
    /** TDS Reply packet. */
    public static final byte REPLY_PKT = 4;
    /** TDS Cancel packet. */
    public static final byte CANCEL_PKT = 6;
    /** TDS MSDTC packet. */
    public static final byte MSDTC_PKT = 14;
    /** TDS 5.0 Query packet. */
    public static final byte SYBQUERY_PKT = 15;
    /** TDS 7.0 Login packet. */
    public static final byte MSLOGIN_PKT = 16;
    /** TDS 7.0 NTLM Authentication packet. */
    public static final byte NTLMAUTH_PKT = 17;
    /** SQL 2000 prelogin negotiation packet. */
    public static final byte PRELOGIN_PKT = 18;
    /** SSL Mode - Login packet must be encrypted. */
    public static final int SSL_ENCRYPT_LOGIN = 0;
    /** SSL Mode - Client requested force encryption. */
    public static final int SSL_CLIENT_FORCE_ENCRYPT = 1;
    /** SSL Mode - No server certificate installed. */
    public static final int SSL_NO_ENCRYPT = 2;
    /** SSL Mode - Server requested force encryption. */
    public static final int SSL_SERVER_FORCE_ENCRYPT = 3;

    //
    // Sub packet types
    //
    /** TDS 5.0 Parameter format token. */
    private static final byte TDS5_PARAMFMT2_TOKEN  = (byte) 32;   // 0x20
    /** TDS 5.0 Language token. */
    private static final byte TDS_LANG_TOKEN        = (byte) 33;   // 0x21
    /** TSD 5.0 Wide result set token. */
    private static final byte TDS5_WIDE_RESULT      = (byte) 97;   // 0x61
    /** TDS 5.0 Close token. */
    private static final byte TDS_CLOSE_TOKEN       = (byte) 113;  // 0x71
    /** TDS DBLIB Offsets token. */
    private static final byte TDS_OFFSETS_TOKEN     = (byte) 120;  // 0x78
    /** TDS Procedure call return status token. */
    private static final byte TDS_RETURNSTATUS_TOKEN= (byte) 121;  // 0x79
    /** TDS Procedure ID token. */
    private static final byte TDS_PROCID            = (byte) 124;  // 0x7C
    /** TDS 7.0 Result set column meta data token. */
    private static final byte TDS7_RESULT_TOKEN     = (byte) 129;  // 0x81
    /** TDS 7.0 Computed Result set column meta data token. */
    private static final byte TDS7_COMP_RESULT_TOKEN= (byte) 136;  // 0x88
    /** TDS 4.2 Column names token. */
    private static final byte TDS_COLNAME_TOKEN     = (byte) 160;  // 0xA0
    /** TDS 4.2 Column meta data token. */
    private static final byte TDS_COLFMT_TOKEN      = (byte) 161;  // 0xA1
    /** TDS Table name token. */
    private static final byte TDS_TABNAME_TOKEN     = (byte) 164;  // 0xA4
    /** TDS Cursor results column infomation token. */
    private static final byte TDS_COLINFO_TOKEN     = (byte) 165;  // 0xA5
    /** TDS Optional command token. */
    private static final byte TDS_OPTIONCMD_TOKEN   = (byte) 166;  // 0xA6
    /** TDS Computed result set names token. */
    private static final byte TDS_COMP_NAMES_TOKEN  = (byte) 167;  // 0xA7
    /** TDS Computed result set token. */
    private static final byte TDS_COMP_RESULT_TOKEN = (byte) 168;  // 0xA8
    /** TDS Order by columns token. */
    private static final byte TDS_ORDER_TOKEN       = (byte) 169;  // 0xA9
    /** TDS error result token. */
    private static final byte TDS_ERROR_TOKEN       = (byte) 170;  // 0xAA
    /** TDS Information message token. */
    private static final byte TDS_INFO_TOKEN        = (byte) 171;  // 0xAB
    /** TDS Output parameter value token. */
    private static final byte TDS_PARAM_TOKEN       = (byte) 172;  // 0xAC
    /** TDS Login acknowledgement token. */
    private static final byte TDS_LOGINACK_TOKEN    = (byte) 173;  // 0xAD
    /** TDS control token. */
    private static final byte TDS_CONTROL_TOKEN     = (byte) 174;  // 0xAE
    /** TDS Result set data row token. */
    private static final byte TDS_ROW_TOKEN         = (byte) 209;  // 0xD1
    /** TDS Computed result set data row token. */
    private static final byte TDS_ALTROW            = (byte) 211;  // 0xD3
    /** TDS 5.0 parameter value token. */
    private static final byte TDS5_PARAMS_TOKEN     = (byte) 215;  // 0xD7
    /** TDS 5.0 capabilities token. */
    private static final byte TDS_CAP_TOKEN         = (byte) 226;  // 0xE2
    /** TDS environment change token. */
    private static final byte TDS_ENVCHANGE_TOKEN   = (byte) 227;  // 0xE3
    /** TDS 5.0 message token. */
    private static final byte TDS_MSG50_TOKEN       = (byte) 229;  // 0xE5
    /** TDS 5.0 RPC token. */
    private static final byte TDS_DBRPC_TOKEN       = (byte) 230;  // 0xE6
    /** TDS 5.0 Dynamic SQL token. */
    private static final byte TDS5_DYNAMIC_TOKEN    = (byte) 231;  // 0xE7
    /** TDS 5.0 parameter descriptor token. */
    private static final byte TDS5_PARAMFMT_TOKEN   = (byte) 236;  // 0xEC
    /** TDS 7.0 NTLM authentication challenge token. */
    private static final byte TDS_AUTH_TOKEN        = (byte) 237;  // 0xED
    /** TDS 5.0 Result set column meta data token. */
    private static final byte TDS_RESULT_TOKEN      = (byte) 238;  // 0xEE
    /** TDS done token. */
    private static final byte TDS_DONE_TOKEN        = (byte) 253;  // 0xFD DONE
    /** TDS done procedure token. */
    private static final byte TDS_DONEPROC_TOKEN    = (byte) 254;  // 0xFE DONEPROC
    /** TDS done in procedure token. */
    private static final byte TDS_DONEINPROC_TOKEN  = (byte) 255;  // 0xFF DONEINPROC

    //
    // Environment change payload codes
    //
    /** Environment change: database changed. */
    private static final byte TDS_ENV_DATABASE      = (byte) 1;
    /** Environment change: language changed. */
    private static final byte TDS_ENV_LANG          = (byte) 2;
    /** Environment change: charset changed. */
    private static final byte TDS_ENV_CHARSET       = (byte) 3;
    /** Environment change: network packet size changed. */
    private static final byte TDS_ENV_PACKSIZE      = (byte) 4;
    /** Environment change: locale changed. */
    private static final byte TDS_ENV_LCID          = (byte) 5;
    /** Environment change: TDS 8 collation changed. */
    private static final byte TDS_ENV_SQLCOLLATION  = (byte) 7; // TDS8 Collation

    //
    // Static variables used only for performance
    //
    /** Used to optimize the {@link #getParameters()} call */
    private static final ParamInfo[] EMPTY_PARAMETER_INFO = new ParamInfo[0];

    //
    // End token status bytes
    //
    /** Done: more results are expected. */
    private static final byte DONE_MORE_RESULTS     = (byte) 0x01;
    /** Done: command caused an error. */
    private static final byte DONE_ERROR            = (byte) 0x02;
    /** Done: There is a valid row count. */
    private static final byte DONE_ROW_COUNT        = (byte) 0x10;
    /** Done: Cancel acknowledgement. */
    static final byte DONE_CANCEL                   = (byte) 0x20;
    /**
     * Done: Response terminator (if more than one request packet is sent, each
     * response is terminated by a DONE packet with this flag set).
     */
    private static final byte DONE_END_OF_RESPONSE  = (byte) 0x80;

    //
    // Prepared SQL types
    //
    /** Do not prepare SQL */
    public static final int UNPREPARED = 0;
    /** Prepare SQL using temporary stored procedures */
    public static final int TEMPORARY_STORED_PROCEDURES = 1;
    /** Prepare SQL using sp_executesql */
    public static final int EXECUTE_SQL = 2;
    /** Prepare SQL using sp_prepare and sp_execute */
    public static final int PREPARE = 3;

    //
    // Sybase capability flags
    //
    /** Sybase char and binary > 255.*/
    static final int SYB_LONGDATA    = 1;
    /** Sybase date and time data types.*/
    static final int SYB_DATETIME    = 2;
    /** Sybase nullable bit type.*/
    static final int SYB_BITNULL     = 4;
    /** Sybase extended column meta data.*/
    static final int SYB_EXTCOLINFO  = 8;
    /** Sybase univarchar etc. */
    static final int SYB_UNICODE     = 16;
    /** Sybase 15+ unitext. */
    static final int SYB_UNITEXT     = 32;
    /** Sybase 15+ bigint. */
    static final int SYB_BIGINT      = 64;

    /** Cancel has been generated by <code>Statement.cancel()</code>. */
    private final static int ASYNC_CANCEL = 0;
    /** Cancel has been generated by a query timeout. */