StatementHandler.java

/* Copyright (c) 2001-2024, The HSQL Development Group
 * All rights reserved.
 *
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 *
 * Redistributions of source code must retain the above copyright notice, this
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 *
 * Redistributions in binary form must reproduce the above copyright notice,
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package org.hsqldb;

import org.hsqldb.HsqlNameManager.HsqlName;
import org.hsqldb.error.Error;
import org.hsqldb.error.ErrorCode;
import org.hsqldb.lib.OrderedHashSet;
import org.hsqldb.lib.OrderedIntHashSet;
import org.hsqldb.result.Result;

/**
 * Implementation of Statement for condition handler objects.<p>
 *
 * @author Fred Toussi (fredt@users dot sourceforge.net)
 * @version 2.7.3
 * @since 1.9.0
 */
public class StatementHandler extends Statement {

    public static final int NONE          = 0;
    public static final int SQL_EXCEPTION = 1;
    public static final int SQL_WARNING   = 2;
    public static final int SQL_NOT_FOUND = 3;
    public static final int SQL_STATE     = 4;

    //
    public static final int CONTINUE = 5;
    public static final int EXIT     = 6;
    public static final int UNDO     = 7;

    //
    public final int handlerType;

    //
    private OrderedIntHashSet      conditionGroups = new OrderedIntHashSet();
    private OrderedHashSet<String> conditionStates = new OrderedHashSet<>();
    private Statement              statement;

    //
    public static final StatementHandler[] emptyExceptionHandlerArray =
        new StatementHandler[]{};

    StatementHandler(int handlerType) {
        super(StatementTypes.HANDLER, StatementTypes.X_SQL_CONTROL);

        this.handlerType = handlerType;
    }

    public void addConditionState(String sqlState) {

        boolean result = conditionStates.add(sqlState);

        result &= conditionGroups.isEmpty();

        if (!result) {
            throw Error.error(ErrorCode.X_42612);
        }
    }

    public void addConditionType(int conditionType) {

        boolean result = conditionGroups.add(conditionType);

        result &= conditionStates.isEmpty();

        if (!result) {
            throw Error.error(ErrorCode.X_42612);
        }
    }

    public void addStatement(Statement s) {
        statement = s;
    }

    public boolean handlesConditionType(int type) {
        return conditionGroups.contains(type);
    }

    public boolean handlesCondition(String sqlState) {

        if (conditionStates.contains(sqlState)) {
            return true;
        }

        String conditionClass = sqlState.substring(0, 2);

        if (conditionStates.contains(conditionClass)) {
            return true;
        }

        if (conditionClass.equals("01")) {
            return conditionGroups.contains(SQL_WARNING);
        }

        if (conditionClass.equals("02")) {
            return conditionGroups.contains(SQL_NOT_FOUND);
        }

        return conditionGroups.contains(SQL_EXCEPTION);
    }

    public int[] getConditionTypes() {
        return conditionGroups.toArray();
    }

    public String[] getConditionStates() {

        String[] array = new String[conditionStates.size()];

        conditionStates.toArray(array);

        return array;
    }

    public void resolve(Session session) {

        if (statement != null) {
            statement.resolve(session);

            readTableNames  = statement.getTableNamesForRead();
            writeTableNames = statement.getTableNamesForWrite();
        }
    }

    public Result execute(Session session) {

        if (statement != null) {
            return statement.execute(session);
        } else {
            return Result.updateZeroResult;
        }
    }

    public String describe(Session session) {
        return "";
    }

    public OrderedHashSet<HsqlName> getReferences() {

        if (statement == null) {
            return new OrderedHashSet<>();
        }

        return statement.getReferences();
    }

    public String getSQL() {

        StringBuilder sb = new StringBuilder(64);
        String        s;

        s = handlerType == CONTINUE
            ? Tokens.T_CONTINUE
            : handlerType == EXIT
              ? Tokens.T_EXIT
              : Tokens.T_UNDO;

        sb.append(Tokens.T_DECLARE)
          .append(' ')
          .append(s)
          .append(' ')
          .append(Tokens.T_HANDLER)
          .append(' ')
          .append(Tokens.T_FOR)
          .append(' ');

        for (int i = 0; i < conditionStates.size(); i++) {
            if (i > 0) {
                sb.append(',');
            }

            sb.append(Tokens.T_SQLSTATE)
              .append(' ')
              .append('\'')
              .append(conditionStates.get(i))
              .append('\'');
        }

        for (int i = 0; i < conditionGroups.size(); i++) {
            if (i > 0) {
                sb.append(',');
            }

            switch (conditionGroups.get(i)) {

                case SQL_EXCEPTION :
                    sb.append(Tokens.T_SQLEXCEPTION);
                    break;

                case SQL_WARNING :
                    sb.append(Tokens.T_SQLWARNING);
                    break;

                case SQL_NOT_FOUND :
                    sb.append(Tokens.T_NOT).append(' ').append(Tokens.FOUND);
                    break;
            }
        }

        if (statement != null) {
            sb.append(' ').append(statement.getSQL());
        }

        return sb.toString();
    }

    public boolean isCatalogLock(int model) {
        return false;
    }

    public boolean isCatalogChange() {
        return false;
    }
}