RowSetNavigatorDataChangeMemory.java

/* Copyright (c) 2001-2011, The HSQL Development Group
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 *
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package org.hsqldb.navigator;

import java.io.IOException;

import org.hsqldb.Row;
import org.hsqldb.Session;
import org.hsqldb.error.Error;
import org.hsqldb.error.ErrorCode;
import org.hsqldb.lib.ArrayUtil;
import org.hsqldb.lib.OrderedLongKeyHashMap;
import org.hsqldb.result.ResultMetaData;
import org.hsqldb.rowio.RowInputInterface;
import org.hsqldb.rowio.RowOutputInterface;
import org.hsqldb.types.Type;

/*
 * All-in-memory implementation of RowSetNavigator for delete and update
 * operations.
 *
 * @author Fred Toussi (fredt@users dot sourceforge.net)
 * @version 2.2.7
 * @since 1.9.0
 */
public class RowSetNavigatorDataChangeMemory
implements RowSetNavigatorDataChange {

    public static RowSetNavigatorDataChangeMemory emptyRowSet =
        new RowSetNavigatorDataChangeMemory(null);
    int                   size;
    int                   currentPos = -1;
    OrderedLongKeyHashMap list;
    Session               session;

    public RowSetNavigatorDataChangeMemory(Session session) {
        this.session = session;
        list         = new OrderedLongKeyHashMap(64, true);
    }

    public void release() {

        beforeFirst();
        list.clear();

        size = 0;
    }

    public int getSize() {
        return size;
    }

    public int getRowPosition() {
        return currentPos;
    }

    public boolean next() {

        if (currentPos < size - 1) {
            currentPos++;

            return true;
        }

        currentPos = size - 1;

        return false;
    }

    public boolean beforeFirst() {

        currentPos = -1;

        return true;
    }

    public Row getCurrentRow() {
        return (Row) list.getValueByIndex(currentPos);
    }

    public Object[] getCurrentChangedData() {
        return (Object[]) list.getSecondValueByIndex(currentPos);
    }

    public int[] getCurrentChangedColumns() {
        return (int[]) list.getThirdValueByIndex(currentPos);
    }

    // reading and writing
    public void write(RowOutputInterface out,
                      ResultMetaData meta) throws IOException {}

    public void read(RowInputInterface in,
                     ResultMetaData meta) throws IOException {}

    public void endMainDataSet() {}

    public boolean addRow(Row row) {

        int lookup = list.getLookup(row.getId());

        if (lookup == -1) {
            list.put(row.getId(), row, null);

            size++;

            return true;
        } else {
            if (list.getSecondValueByIndex(lookup) != null) {
                if (session.database.sqlEnforceTDCD) {
                    throw Error.error(ErrorCode.X_27000);
                }

                list.setSecondValueByIndex(lookup, null);
                list.setThirdValueByIndex(lookup, null);

                return true;
            }

            return false;
        }
    }

    public Object[] addRow(Session session, Row row, Object[] data,
                           Type[] types, int[] columnMap) {

        long rowId  = row.getId();
        int  lookup = list.getLookup(rowId);

        if (lookup == -1) {
            list.put(rowId, row, data);
            list.setThirdValueByIndex(size, columnMap);

            size++;

            return data;
        } else {
            Object[] rowData = ((Row) list.getFirstByLookup(lookup)).getData();
            Object[] currentData =
                (Object[]) list.getSecondValueByIndex(lookup);

            if (currentData == null) {
                if (session.database.sqlEnforceTDCD) {
                    throw Error.error(ErrorCode.X_27000);
                } else {
                    return null;
                }
            }

            for (int i = 0; i < columnMap.length; i++) {
                int j = columnMap[i];

                if (types[j].compare(session, data[j], currentData[j]) != 0) {
                    if (types[j].compare(session, rowData[j], currentData[j])
                            != 0) {
                        if (session.database.sqlEnforceTDCU) {
                            throw Error.error(ErrorCode.X_27000);
                        }
                    } else {
                        currentData[j] = data[j];
                    }
                }
            }

            int[] currentMap = (int[]) list.getThirdValueByIndex(lookup);

            currentMap = ArrayUtil.union(currentMap, columnMap);

            list.setThirdValueByIndex(lookup, currentMap);

            return currentData;
        }
    }

    public boolean containsDeletedRow(Row row) {

        int lookup = list.getLookup(row.getId());

        if (lookup == -1) {
            return false;
        }

        Object[] currentData = (Object[]) list.getSecondValueByIndex(lookup);

        return currentData == null;
    }
}