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package org.hsqldb;

import org.hsqldb.lib.LongLookup;
import org.hsqldb.persist.CachedObject;
import org.hsqldb.persist.PersistentStore;
import org.hsqldb.rowio.RowInputInterface;
import org.hsqldb.rowio.RowOutputInterface;
import org.hsqldb.types.DateTimeType;
import org.hsqldb.types.TimestampData;

Base class for a database row object.
Author:
Fred Toussi (fredt@users dot sourceforge dot net)
Version:
2.5.0/**
 * Base class for a database row object.
 *
 * @author Fred Toussi (fredt@users dot sourceforge dot net)
 * @version 2.5.0
 */
public class Row implements CachedObject {

    long                      position;
    Object[]                  rowData;
    public volatile RowAction rowAction;
    protected TableBase       table;

    public RowAction getAction() {
        return rowAction;
    }

    
 Default constructor used only in subclasses.
/**
     *  Default constructor used only in subclasses.
     */
    public Row(TableBase table, Object[] data) {
        this.table   = table;
        this.rowData = data;
    }

    public Object getField(int col) {
        return rowData[col];
    }

    
Returns the array of fields in the database row.
/**
     * Returns the array of fields in the database row.
     */
    public Object[] getData() {
        return rowData;
    }

    public Object[] getDataCopy() {

        Object[] newData = new Object[rowData.length];
        Object[] data    = getData();

        System.arraycopy(data, 0, newData, 0, data.length);

        return newData;
    }

    boolean isDeleted(Session session, PersistentStore store) {

        RowAction action;
        Row       row = (Row) store.get(this, false);

        if (row == null) {
            return true;
        }

        action = row.rowAction;

        if (action == null) {
            return false;
        }

        return !action.canRead(session, TransactionManager.ACTION_READ);
    }

    public TimestampData getSystemStartVersion() {

        if (table.isSystemVersioned) {
            TimestampData ts = (TimestampData) getField(
                ((Table) table).systemPeriodStartColumn);

            return ts;
        }

        return DateTimeType.epochTimestamp;
    }

    public TimestampData getSystemEndVersion() {

        if (table.isSystemVersioned) {
            TimestampData ts = (TimestampData) getField(
                ((Table) table).systemPeriodEndColumn);

            return ts;
        }

        return DateTimeType.epochLimitTimestamp;
    }

    public boolean isCurrentSystemVersion() {

        if (table.isSystemVersioned) {
            TimestampData ts = (TimestampData) getField(
                ((Table) table).systemPeriodEndColumn);

            return DateTimeType.epochLimitSeconds == ts.getSeconds();
        }

        return true;
    }

    public void setStorageSize(int size) {}

    public int getStorageSize() {
        return 0;
    }

    public final boolean isInvariable() {
        return false;
    }

    public final boolean isBlock() {
        return false;
    }

    public boolean isMemory() {
        return true;
    }

    public void updateAccessCount(int count) {}

    public int getAccessCount() {
        return 0;
    }

    public long getPos() {
        return position;
    }

    public long getId() {
        return ((long) table.getId() << 40) + position;
    }

    public void setPos(long pos) {
        position = pos;
    }

    public boolean isNew() {
        return false;
    }

    public boolean hasChanged() {
        return false;
    }

    public void setChanged(boolean flag) {}

    public boolean isKeepInMemory() {
        return true;
    }

    public boolean keepInMemory(boolean keep) {
        return true;
    }

    public boolean isInMemory() {
        return true;
    }

    public void setInMemory(boolean in) {}

    public void delete(PersistentStore store) {}

    public void restore() {}

    public void destroy() {}

    public int getRealSize(RowOutputInterface out) {
        return 0;
    }

    public TableBase getTable() {
        return table;
    }

    public int getDefaultCapacity() {
        return 0;
    }

    public void read(RowInputInterface in) {}

    public void write(RowOutputInterface out) {}

    public void write(RowOutputInterface out, LongLookup lookup) {}

    
Lifetime scope of this method is limited depends on the operations
performed. Rows deleted completely can equal rows produced later.
This can return invalid results if used with deleted rows.
Params:
obj – row to compare
Returns:
boolean/**
     * Lifetime scope of this method is limited depends on the operations
     * performed. Rows deleted completely can equal rows produced later.
     * This can return invalid results if used with deleted rows.
     *
     * @param obj row to compare
     * @return boolean
     */
    public boolean equals(Object obj) {

        if (obj == this) {
            return true;
        }

        if (obj instanceof Row) {
            return ((Row) obj).table == table
                   && ((Row) obj).position == position;
        }

        return false;
    }

    
Hash code is always valid.
Returns:
file position of row/**
     * Hash code is always valid.
     *
     * @return file position of row
     */
    public int hashCode() {
        return (int) position;
    }
}