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*
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package org.hsqldb;
import java.io.IOException;
import org.hsqldb.index.NodeAVL;
import org.hsqldb.persist.PersistentStore;
import org.hsqldb.rowio.RowInputInterface;
import org.hsqldb.rowio.RowOutputInterface;
// fredt@users 20021205 - path 1.7.2 - enhancements
// fredt@users 20021215 - doc 1.7.2 - javadoc comments
/**
* Implementation of rows for tables with memory resident indexes and
* disk-based data, such as TEXT tables.
*
* @author Bob Preston (sqlbob@users dot sourceforge.net)
* @author Fred Toussi (fredt@users dot sourceforge.net)
* @version 1.9.0
* @version 1.7.0
*/
public class RowAVLDiskData extends RowAVL {
PersistentStore store;
int accessCount;
boolean hasDataChanged;
int storageSize;
/**
* Constructor for new rows.
*/
public RowAVLDiskData(PersistentStore store, TableBase t, Object[] o) {
super(t, o);
setNewNodes();
hasDataChanged = true;
this.store = store;
}
/**
* Constructor when read from the disk into the Cache. The link with
* the Nodes is made separetly.
*/
public RowAVLDiskData(PersistentStore store, TableBase t,
RowInputInterface in) throws IOException {
super(t, (Object[]) null);
setNewNodes();
position = in.getPos();
storageSize = in.getSize();
rowData = in.readData(table.getColumnTypes());
hasDataChanged = false;
this.store = store;
}
public void setData(Object[] data) {
this.rowData = data;
}
public Object[] getData() {
if (rowData == null) {
store.get(this, false);
} else {
accessCount++;
}
return rowData;
}
/**
* Used when data is read from the disk into the Cache the first time.
* New Nodes are created which are then indexed.
*/
public void setNewNodes() {
int index = table.getIndexCount();
nPrimaryNode = new NodeAVL(this);
NodeAVL n = nPrimaryNode;
for (int i = 1; i < index; i++) {
n.nNext = new NodeAVL(this);
n = n.nNext;
}
}
public NodeAVL insertNode(int index) {
NodeAVL backnode = getNode(index - 1);
NodeAVL newnode = new NodeAVL(this);
newnode.nNext = backnode.nNext;
backnode.nNext = newnode;
return newnode;
}
/**
* Used when data is re-read from the disk into the Cache. The Row is
* already indexed so it is linked with the Node in the primary index.
* the Nodes is made separetly.
*/
void setPrimaryNode(NodeAVL primary) {
nPrimaryNode = primary;
}
public int getRealSize(RowOutputInterface out) {
return out.getSize((RowAVL) this);
}
/**
* Writes the data to disk. Unlike CachedRow, hasChanged is never set
* to true when changes are made to the Nodes. (Nodes are in-memory).
* The only time this is used is when a new Row is added to the Caches.
*/
public void write(RowOutputInterface out) {
out.writeSize(storageSize);
out.writeData(getData(), table.colTypes);
out.writeEnd();
hasDataChanged = false;
}
public boolean hasChanged() {
return hasDataChanged;
}
public void updateAccessCount(int count) {
accessCount = count;
}
public int getAccessCount() {
return accessCount;
}
public int getStorageSize() {
return storageSize;
}
public void setStorageSize(int size) {
storageSize = size;
}
/**
* Sets the file position for the row and registers the row with
* the table.
*
* @param pos position in data file
*/
public void setPos(int pos) {
position = pos;
}
public boolean isMemory() {
return true;
}
/**
* With the current implementation of TEXT table updates and inserts,
* the lifetime scope of this method extends until redefinition of table
* data source or shutdown.
*
* @param obj the reference object with which to compare.
* @return <code>true</code> if this object is the same as the obj argument;
* <code>false</code> otherwise.
*/
public boolean equals(Object obj) {
return obj == this;
}
public boolean isInMemory() {
return rowData != null;
}
public boolean isKeepInMemory() {
return false;
}
public boolean keepInMemory(boolean keep) {
return true;
}
public void setInMemory(boolean in) {
if (!in) {
rowData = null;
}
}
}