result.java

hsqldb是100％java实现的数据库,是一个开放源代码的JAVA数据库 l 具有标准的SQL语法和JAVA接口 l HSQLDB可以自由使用和分发 l 非常简洁和快速的

/* Copyright (c) 1995-2000, The Hypersonic SQL Group.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of the Hypersonic SQL Group nor the names of its
 * contributors may be used to endorse or promote products derived from this
 * software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE HYPERSONIC SQL GROUP,
 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals 
 * on behalf of the Hypersonic SQL Group.
 *
 *
 * For work added by the HSQL Development Group:
 *
 * Copyright (c) 2001-2005, The HSQL Development Group
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of the HSQL Development Group nor the names of its
 * contributors may be used to endorse or promote products derived from this
 * software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL HSQL DEVELOPMENT GROUP, HSQLDB.ORG,
 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */


package org.hsqldb;

import java.io.DataInput;
import java.io.IOException;
import java.io.OutputStream;
import java.util.NoSuchElementException;

import org.hsqldb.lib.Iterator;
import org.hsqldb.rowio.RowInputBinary;
import org.hsqldb.rowio.RowOutputBinary;

// fredt@users 20020130 - patch 1.7.0 by fredt
// to ensure consistency of r.rTail r.iSize in all operations
// methods for set operations moved here from Select.java
// tony_lai@users 20020820 - patch 595073 - duplicated exception msg
// fredt@users 20030801 - patch 1.7.2 - separate metadata and polymophic serialisation
// boucherb@users 200307/8 - various, in support of fred's work over the same time period

/**
 *  The primary unit of comunication between Connection, Server and Session
 *  objects.
 *
 *  An HSQLDB Result object encapsulates all requests (such as to alter or
 *  query session settings, to allocate and execute statements, etc.) and all
 *  responses (such as exception indications, update counts, result sets and
 *  result set metadata). It also implements the HSQL wire protocol for
 *  comunicating all such requests and responses across the network.
 *
 * Extensively rewritten and extended in successive versions of HSQLDB.
 *
 * @author Thomas Mueller (Hypersonic SQL Group)
 * @version 1.8.0
 * @since Hypersonic SQL
 */
public class Result {

    // record list
    public Record  rRoot;
    private Record rTail;
    private int    size;

    // transient - number of significant columns
    private int significantColumns;

    // type of result
    public int mode;

//    boolean isMulti;
    // database ID
    int databaseID;

    // session ID
    int sessionID;

    // user / password or error strings
    String mainString;
    String subString;

    // database name
    String subSubString;

    // the exception if this is an error
    private Throwable exception;

    // prepared statement id / error vendor code
    int statementID;

    // max rows (out) or update count (in)
    int                   updateCount;
    public ResultMetaData metaData;

    /** A Result object's metadata */
    public static class ResultMetaData {

        // always resolved
        public String[]  colLabels;
        public String[]  tableNames;
        public String[]  colNames;
        public boolean[] isLabelQuoted;
        public int[]     colTypes;
        public int[]     colSizes;
        public int[]     colScales;

        // extra attrs, sometimes resolved
        public String[]  catalogNames;
        public String[]  schemaNames;
        public int[]     colNullable;
        public boolean[] isIdentity;
        public boolean[] isWritable;
        public int[]     paramMode;

        // It's possible to do better than java.lang.Object
        // for type OTHER if the expression generating the value
        // is of type FUNCTION.  This applies to result set columns
        // whose value is the result of a SQL function call and
        // especially to the arguments and return value of a CALL
        public String[] classNames;
        boolean         isParameterDescription;

        ResultMetaData() {}

        ResultMetaData(int n) {
            prepareData(n);
        }

        /**
         *  Method declaration
         *
         * @param  columns
         */
        private void prepareData(int columns) {

            colLabels     = new String[columns];
            tableNames    = new String[columns];
            colNames      = new String[columns];
            isLabelQuoted = new boolean[columns];
            colTypes      = new int[columns];
            colSizes      = new int[columns];
            colScales     = new int[columns];
            catalogNames  = new String[columns];
            schemaNames   = new String[columns];
            colNullable   = new int[columns];
            isIdentity    = new boolean[columns];
            isWritable    = new boolean[columns];
            classNames    = new String[columns];
        }

        public int[] getParameterTypes() {
            return colTypes;
        }

        boolean isTableColumn(int i) {
            return tableNames[i] != null && tableNames[i].length() > 0
                   && colNames[i] != null && colNames[i].length() > 0;
        }

        private void decodeTableColumnAttrs(int in, int i) {

            colNullable[i] = in & 0x0000000f;
            isIdentity[i]  = (in & 0x00000010) != 0;
            isWritable[i]  = (in & 0x00000020) != 0;
        }

        private void writeTableColumnAttrs(RowOutputBinary out,
                                           int i)
                                           throws IOException, HsqlException {

            // HSQLDB also ignores precision and scale for all types except
            // XXXCHAR, for which it may (or may not) perform some trimming/padding.
            // All in all, it's currently meaningless (indeed misleading) to
            // transmit and report the values, as the data typically will
            // not be constrained accordingly.
//        switch(colType[i]) {
//            // As early as SQL 92, these are allowed to have a scale.
//            // However, DatabaseCommandInterpreter.processCreateColumn
//            // does not currently handle this correctly and will assign
//            // a precision instead of a scale if TIME(s) or TIMESTAMP(s)
//            // is specified
//            case Types.TIME :
//            case Types.TIMESTAMP :
//                  out.writeIntData(colScale[i]);
//                  break;
//            case Types.DECIMAL :
//            case Types.NUMERIC : {
//                out.writeIntData(colScale[i]);
//            } // fall through
//            // Apparently, SQL 92 specifies that FLOAT can have
//            // a declared precision, which is typically the number of
//            // bits (not binary digits).  In any case, this is somewhat
//            // meaningless under HSQLDB/Java, in that we use java.lang.Double
//            // to represent SQL FLOAT
//            case Types.FLOAT :
//            // It's legal to declare precision for these, although HSQLDB
//            // currently does not use it to constrain values
//            case Types.BINARY :
//            case Types.VARBINARY :
//            case Types.LONGVARBINARY :
//            // possibly, but not universally acted upon (trimmming/padding)
//            case Types.CHAR  :
//            case Types.VARCHAR :
//            case Types.LONGVARCHAR : {
//                out.writeIntData(colSize[i]);
//            }
//        }
            out.writeIntData(encodeTableColumnAttrs(i));
            out.writeString(catalogNames[i] == null ? ""
                                                    : catalogNames[i]);
            out.writeString(schemaNames[i] == null ? ""
                                                   : schemaNames[i]);
        }

        private int encodeTableColumnAttrs(int i) {

            int out = colNullable[i];    // always between 0x00 and 0x02

            if (isIdentity[i]) {
                out |= 0x00000010;
            }

            if (isWritable[i]) {
                out |= 0x00000020;
            }

            return out;
        }

        private void readTableColumnAttrs(RowInputBinary in,
                                          int i)
                                          throws IOException, HsqlException {

            decodeTableColumnAttrs(in.readIntData(), i);

            catalogNames[i] = in.readString();
            schemaNames[i]  = in.readString();
        }

        ResultMetaData(RowInputBinary in,
                       int mode) throws HsqlException, IOException {

            int l = in.readIntData();

            prepareData(l);

            if (mode == ResultConstants.PARAM_META_DATA) {
                isParameterDescription = true;
                paramMode              = new int[l];
            }

            for (int i = 0; i < l; i++) {
                colTypes[i] = in.readType();

                // fredt - 1.8.0 added
                colSizes[i]   = in.readIntData();
                colScales[i]  = in.readIntData();
                colLabels[i]  = in.readString();
                tableNames[i] = in.readString();
                colNames[i]   = in.readString();
                classNames[i] = in.readString();

                if (isTableColumn(i)) {
                    readTableColumnAttrs(in, i);
                }

                if (mode == ResultConstants.PARAM_META_DATA) {
                    paramMode[i] = in.readIntData();
                }
            }
        }

        void write(RowOutputBinary out,
                   int colCount) throws HsqlException, IOException {

            out.writeIntData(colCount);

            for (int i = 0; i < colCount; i++) {
                out.writeType(colTypes[i]);

                // fredt - 1.8.0 added
                out.writeIntData(colSizes[i]);
                out.writeIntData(colScales[i]);
                out.writeString(colLabels[i] == null ? ""
                                                     : colLabels[i]);
                out.writeString(tableNames[i] == null ? ""
                                                      : tableNames[i]);
                out.writeString(colNames[i] == null ? ""
                                                    : colNames[i]);
                out.writeString(classNames[i] == null ? ""
                                                      : classNames[i]);

                if (isTableColumn(i)) {
                    writeTableColumnAttrs(out, i);
                }

                if (isParameterDescription) {
                    out.writeIntData(paramMode[i]);
                }
            }
        }
    }

    /**
     *  General constructor
     */
    public Result(int type) {

        mode = type;

/*
        if (type == ResultConstants.MULTI) {
            isMulti = true;
        }
*/
        if (type == ResultConstants.DATA
                || type == ResultConstants.PARAM_META_DATA
                || type == ResultConstants.SQLEXECUTE
                || type == ResultConstants.SETSESSIONATTR) {
            metaData = new ResultMetaData();
        }
    }

    Result(ResultMetaData md) {

        mode               = ResultConstants.DATA;
        significantColumns = md.colTypes.length;
        metaData           = md;
    }

// fredt@users 20020221 - patch 513005 by sqlbob@users (RMP)

    /**
     *  Constructor for errors
     *
     * @param  error error message
     * @param  state   sql state
     * @param  code   vendor code
     */
    Result(String error, String state, int code) {

        mode         = ResultConstants.ERROR;
        mainString   = error;
        subString    = state;
        statementID  = code;
        subSubString = "";
    }

    /**
     *  Only used with DATA and PARAM_META_DATA results
     *
     * @param  columns
     */
    Result(int type, int columns) {

        metaData = new ResultMetaData();

        metaData.prepareData(columns);

        if (type == ResultConstants.PARAM_META_DATA) {
            metaData.isParameterDescription = true;
            metaData.paramMode              = new int[columns];
        }

        mode               = type;
        significantColumns = columns;
    }

    /**
     * For BATCHEXECUTE and BATCHEXECDIRECT
     */
    public Result(int type, int[] types, int id) {

        mode               = type;
        metaData           = new ResultMetaData();
        metaData.colTypes  = types;
        significantColumns = types.length;
        statementID        = id;
    }

    /**
     *  Constructor declaration
     *
     * @param  in
     * @exception  HsqlException  Description of the Exception
     */
    Result(RowInputBinary in) throws HsqlException {

        try {
            mode = in.readIntData();

            if (mode == ResultConstants.MULTI) {
                readMultiResult(in);

                return;
            }

            databaseID = in.readIntData();
            sessionID  = in.readIntData();

            switch (mode) {

                case ResultConstants.GETSESSIONATTR :
                case ResultConstants.SQLDISCONNECT :
                case ResultConstants.SQLSTARTTRAN :
                case ResultConstants.HSQLRESETSESSION :
                    break;

                case ResultConstants.SQLPREPARE :
                    setStatementType(in.readIntData());

                    mainString = in.readString();
                    break;

                case ResultConstants.PREPARE_ACK :
                case ResultConstants.SQLFREESTMT :
                    statementID = in.readIntData();
                    break;

                case ResultConstants.SQLEXECDIRECT :
                    updateCount = in.readIntData();
                    statementID = in.readIntData();
                    mainString  = in.readString();
                    break;

                case ResultConstants.ERROR :
                case ResultConstants.SQLCONNECT :
                    mainString   = in.readString();
                    subString    = in.readString();
                    subSubString = in.readString();
                    statementID  = in.readIntData();

//                    throw Trace.getError(string, code);
                    break;

                case ResultConstants.UPDATECOUNT :
                    updateCount = in.readIntData();
                    break;

                case ResultConstants.SQLENDTRAN : {
                    int type = in.readIntData();

                    setEndTranType(type);                    // endtran type

                    switch (type) {

                        case ResultConstants.SAVEPOINT_NAME_RELEASE :
                        case ResultConstants.SAVEPOINT_NAME_ROLLBACK :
                            mainString = in.readString();    // savepoint name
                    }

                    break;
                }
                case ResultConstants.BATCHEXECUTE :
                case ResultConstants.BATCHEXECDIRECT :
                case ResultConstants.SQLEXECUTE :
                case ResultConstants.SETSESSIONATTR : {
                    updateCount = in.readIntData();
                    statementID = in.readIntData();

                    int l = in.readIntData();

                    metaData           = new ResultMetaData(l);
                    significantColumns = l;

                    for (int i = 0; i < l; i++) {
                        metaData.colTypes[i] = in.readType();
                    }

                    int count = in.readIntData();

                    while (count-- > 0) {
                        add(in.readData(metaData.colTypes));
                    }

                    break;
                }
                case ResultConstants.DATA :
                case ResultConstants.PARAM_META_DATA : {
                    metaData           = new ResultMetaData(in, mode);