de.must.dataobj

Class DataObjectReadOnlyWithCache

java.lang.Object

de.must.dataobj.DataObject

de.must.dataobj.DataObjectReadOnlyWithCache

All Implemented Interfaces:

DataObjectConstructionDetails, EntityInfo, Exemptible

Direct Known Subclasses:

DataObjectForTermReplacement

public abstract class DataObjectReadOnlyWithCache
extends DataObject

DataObject for read-only access with caching.

Field Summary

Fields inherited from class de.must.dataobj.DataObject

changeLogger, columnNames, columnType, htColumnType, INSERTMODE, maxFieldSize, original, UPDATEMODE

Constructor Summary

Constructors

Constructor and Description
DataObjectReadOnlyWithCache(DataObjectConstructionDetails dataObjectConstructionDetails, int maxColumns)
DataObjectReadOnlyWithCache(DataObjectConstructionDetails dataObjectConstructionDetails, int maxColumns, int initialSize)

Method Summary

Modifier and Type	Method and Description
protected boolean	cacheLoad(Identifier identifier)
protected void	cachePut(Identifier identifier)
void	free() Releases external resources.
protected abstract java.lang.String	getReducedColumnSet() Return the reduced column set to optimize database access or null if all fields are needed.
protected void	init() Called by constructor and by data change listener to initialize or reset cache.
boolean	load(Identifier identifier) Loads a row as specified by the primary key.
boolean	save() Saves the current row.
boolean	select(java.lang.String fieldSelection, java.lang.String whereCondition) Invokes a database query for following record requests via nextRow().

Methods inherited from class de.must.dataobj.DataObject

addDataChangeListener, addDataSelectionListener, alertBadUniqueKey, allocateNewIdentifier, checkRecoverConnection, closeIfExists, closePreparedStatementsForWhereCondition, closeQuery, commitIfNotAutoCommit, contains, contains, contains, contains, contains, contains, count, count, count, count, count, count, countThrowException, delete, delete, deleteFreeConditioned, deleteFreeConditioned, deleteFreeConditionedAndCount, discardStatements, ensureMetaDataIsAvailableForAllColumns, finalize, fireDataChanged, getBoolean, getBoolean, getBytes, getColumnCount, getColumnLabel, getColumnLength, getColumnName, getColumnName, getColumnScale, getColumnType, getColumnType, getColumnType, getColumnType, getConnection, getDate, getDate, getDate, getDateFormattedWithShortYear, getDeletionHindrance, getDescription, getDescription, getDouble, getDouble, getEntityId, getFailedQueryExpression, getFloat, getGlobalWhereCondition, getGlobalWhereCondition, getIdentifier, getIdentifyTemplate, getIdentifyValueInt, getIdentifyWhereCondition, getIdManager, getInt, getInt, getIntAsStringZeroSuppressed, getKeyExtendedFieldSelection, getLastException, getLoadException, getLong, getmaxRow, getMode, getNbrOfFittingItems, getNbrOfFittingItems, getNbrOfFittingItems, getNbrOfFittingItems, getNbrOfFittingItems, getNbrOfFittingItems, getObject, getOriginalOf, getQueryException, getRecordingDate, getRecordingUser, getRowCount, getSqlCompareString, getSqlCompareString, getText, getText, getTextNoMatterWhatTypeOfColumn, getTime, getTimestamp, getUniqueKeyName, getWorkedOnBoolean, getWorkedOnDate, getWorkedOnDouble, getWorkedOnInt, getWorkedOnOf, getWorkedOnText, getWorkedOnText, getWorkedOnTime, getWorkedOnTimestamp, insert, isAvailable, isAvailable, isAvailable, isColumnContained, isColumnToUseForGlobalSearch, isDeletionAllowed, isKnownAsBoolean, isMemo, isModified, isModifiedColumn, isQueryFindingRecords, isQueryFindingRecords, load, load, load, load, load, load, loadColumns, loadFirst, logDebug, logError, logError, logError, logInfo, newRow, newRowWithNextIdentifierAllocation, nextColumn, nextRow, openQuery, openQueryThrowException, register, removeDataChangeListener, removeDataSelectionListener, resetColumnPointer, rollbackIfNotAutoCommit, save, save, searchGlobal, searchGlobal, select, select, select, select, select, select, select, select, select, select, select, select, select, selectForStreaming, setBoolean, setChangeLog, setChangeLogger, setColumnNameOfRecordingDate, setConnection, setDate, setDate, setDate, setDouble, setDouble, setDouble, setFloat, setIdentifier, setIdentityValue, setIdentityValue, setIdentityValue, setIdInclOriginal, setIdManager, setInt, setInt, setLong, setNoLogging, setObject, setReadBigDecimalAsInt, setRecordingUser, setRecordingUser, setSilentUpdate, setText, setText, setTime, setTimestamp, sqlExceptionConsequences, sqlSecure, unifyColumnName, unifyColumnNameForHashMapKey, unifyTableName, update, updateIdentifier, updateOrInsert, updateOrInsert

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface de.must.dataobj.EntityInfo

getAttributes, getForeignKeys, getIndices, getTableName

Constructor Detail

DataObjectReadOnlyWithCache

public DataObjectReadOnlyWithCache(DataObjectConstructionDetails dataObjectConstructionDetails,
                                   int maxColumns)

DataObjectReadOnlyWithCache

public DataObjectReadOnlyWithCache(DataObjectConstructionDetails dataObjectConstructionDetails,
                                   int maxColumns,
                                   int initialSize)

Method Detail

init

protected void init()

Called by constructor and by data change listener to initialize or reset cache.

select

public boolean select(java.lang.String fieldSelection,
                      java.lang.String whereCondition)

Description copied from class: DataObject

Invokes a database query for following record requests via nextRow(). Always invoke DataObject.closeQuery() to release table handle in the end.

 public boolean isDeletionAllowed(Identifier identifier) {
   if (doMedien == null) doMedien = new DoMedien();
   doMedien.select("MedienNi, KatalogNi", "KatalogNi = " + identifier.getIntIdentifier());
   while (doMedien.nextRow()) {
     if (!doMedien.isDeletionAllowed(doMedien.getIdentifier())) {
       doMedien.closeQuery();
       return false;
     }
   }
   doMedien.closeQuery();
   return true;
 }
 

Overrides:

select in class DataObject

Parameters:

fieldSelection - a sequence of field names to be accessed, separated by comma

whereCondition - the condition to reduce the result set

Returns:

true if no exception occurred

See Also:

DataObject.openQuery(java.lang.String), DataObject.closeQuery()

load

public boolean load(Identifier identifier)

Description copied from class: DataObject

Loads a row as specified by the primary key.

Overrides:

load in class DataObject

Parameters:

identifier - the primary key value of the row to load

Returns:

true if the wished row was found

getReducedColumnSet

protected abstract java.lang.String getReducedColumnSet()

Return the reduced column set to optimize database access or null if all fields are needed.

Returns:

the reduced column set

cacheLoad

protected boolean cacheLoad(Identifier identifier)

cachePut

protected void cachePut(Identifier identifier)

save

public boolean save()

Description copied from class: DataObject

Saves the current row. Insert or update is distinguished automatically.

Overrides:

save in class DataObject

Returns:

true if any database modification occurred

free

public void free()

Description copied from interface: Exemptible

Releases external resources. May be called manually without waiting for garbage collection to occur.

Specified by:

free in interface Exemptible

Overrides:

free in class DataObject