Nested and Inner Type Summary

Modifier and Type	Class and Description
private static class	CustomLinkResolver.TempDatabaseImpl Subclass of DatabaseImpl which allows us to load tables "on demand" as well as delete the temporary db on close.

Field Summary

Modifier and Type	Field and Description
private static final Random	DB_ID
public static final Database.FileFormat	DEFAULT_FORMAT the default file format used for temp dbs
public static final boolean	DEFAULT_IN_MEMORY temp dbs default to the filesystem, not in memory
public static final Path	DEFAULT_TEMP_DIR temp dbs end up in the system temp dir by default
private final Database.FileFormat	defaultFormat
private final boolean	defaultInMemory
private final Path	defaultTempDir
private static final String	FILE_DB_PREFIX
private static final String	MEM_DB_PREFIX

Constructor Summary

Access Constructor and Description

protected

Access	Constructor and Description
protected	CustomLinkResolver() Creates a CustomLinkResolver using the default behavior for creating temp dbs, see `DEFAULT_FORMAT`, `DEFAULT_IN_MEMORY` and `DEFAULT_TEMP_DIR`.
protected	CustomLinkResolver(Database.FileFormat the default format for the temp db defaultFormat, boolean whether or not the temp db should be entirely in memory by default (while this will be faster, it should only be used if table data is expected to fit entirely in memory) defaultInMemory, Path the default temp dir for a file based temp db (`null` for the system defaqult temp directory) defaultTempDir) Creates a CustomLinkResolver with the given default behavior for creating temp dbs.

CustomLinkResolver()

Creates a CustomLinkResolver using the default behavior for creating temp dbs, see DEFAULT_FORMAT, DEFAULT_IN_MEMORY and DEFAULT_TEMP_DIR.

protected

CustomLinkResolver(Database.FileFormat

the default format for the temp db

defaultFormat, boolean

whether or not the temp db should be entirely in memory by default (while this will be faster, it should only be used if table data is expected to fit entirely in memory)

defaultInMemory, Path

the default temp dir for a file based temp db (null for the system defaqult temp directory)

defaultTempDir)

Creates a CustomLinkResolver with the given default behavior for creating temp dbs.

Method Summary

Modifier and Type	Method and Description
private static void	closeCustomFile(Object customFile)
protected Database	Returns: the temp db for holding the linked table info createTempDb(Object custom file state returned from `loadCustomFile` customFile, Database.FileFormat the access format for the temp db format, boolean whether or not the temp db should be entirely in memory (while this will be faster, it should only be used if table data is expected to fit entirely in memory) inMemory, Path the temp dir for a file based temp db (`null` for the system default temp directory) tempDir, boolean readOnly) Creates a temporary database for holding the table data from linkeeFileName.
private static void	deleteDbFile(Path dbFile)
protected Database.FileFormat	getDefaultFormat()
protected Path	getDefaultTempDirectory()
protected boolean	isDefaultInMemory()
protected abstract Object	Returns: non-`null` if linkeeFileName should be treated as a custom file (using a temp db) or `null` if it should be treated as a normal access db. loadCustomFile(Database the primary database in which the link is defined linkerDb, String the name of the linked file linkeeFileName) Called by `resolveLinkedDatabase` to determine whether the linkeeFileName should be treated as a custom file (thus utiliziing a temp db) or a normal access db (loaded via the default behavior).
protected abstract boolean	Returns: `true` if the table was available in the linked file, `false` otherwise loadCustomTable(Database the temp db instance which should be populated with the relevant table info for the given tableName tempDb, Object custom file state returned from `loadCustomFile` customFile, String the name of the table which is requested from the linked file tableName) Called by an instance of a temp db when a missing table is first requested.
public Database	resolveLinkedDatabase(Database linkerDb, String linkeeFileName) Implements io.github.spannm.jackcess.util.LinkResolver.resolveLinkedDatabase. Custom implementation is: // attempt to load the linkeeFileName as a custom file Object customFile = loadCustomFile(linkerDb, linkeeFileName); if (customFile != null) { // this is a custom file, create and return relevant temp db return createTempDb(customFile, getDefaultFormat(), isDefaultInMemory(), getDefaultTempDirectory()); } // not a custom file, load using the default behavior return LinkResolver.DEFAULT.resolveLinkedDatabase(linkerDb, linkeeFileName);

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

DB_ID	back to summary
private static final Random DB_ID

DEFAULT_FORMAT	back to summary
public static final Database.FileFormat DEFAULT_FORMAT the default file format used for temp dbs

DEFAULT_IN_MEMORY	back to summary
public static final boolean DEFAULT_IN_MEMORY temp dbs default to the filesystem, not in memory

DEFAULT_TEMP_DIR	back to summary
public static final Path DEFAULT_TEMP_DIR temp dbs end up in the system temp dir by default

defaultFormat	back to summary
private final Database.FileFormat defaultFormat

defaultInMemory	back to summary
private final boolean defaultInMemory

defaultTempDir	back to summary
private final Path defaultTempDir

FILE_DB_PREFIX	back to summary
private static final String FILE_DB_PREFIX

MEM_DB_PREFIX	back to summary
private static final String MEM_DB_PREFIX

Constructor Detail

CustomLinkResolver	back to summary
protected CustomLinkResolver() Creates a CustomLinkResolver using the default behavior for creating temp dbs, see `DEFAULT_FORMAT`, `DEFAULT_IN_MEMORY` and `DEFAULT_TEMP_DIR`.

CustomLinkResolver back to summary

CustomLinkResolver	back to summary
protected CustomLinkResolver(Database.FileFormat defaultFormat, boolean defaultInMemory, Path defaultTempDir) Creates a CustomLinkResolver with the given default behavior for creating temp dbs. Parameters defaultFormat:Database.FileFormat the default format for the temp db defaultInMemory:boolean whether or not the temp db should be entirely in memory by default (while this will be faster, it should only be used if table data is expected to fit entirely in memory) defaultTempDir:Path the default temp dir for a file based temp db (`null` for the system defaqult temp directory)

protected CustomLinkResolver(Database.FileFormat defaultFormat, boolean defaultInMemory, Path defaultTempDir)

Creates a CustomLinkResolver with the given default behavior for creating temp dbs.

Parameters

defaultFormat:Database.FileFormat: the default format for the temp db
defaultInMemory:boolean: whether or not the temp db should be entirely in memory by default (while this will be faster, it should only be used if table data is expected to fit entirely in memory)
defaultTempDir:Path: the default temp dir for a file based temp db (null for the system defaqult temp directory)

Method Detail

closeCustomFile	back to summary
private static void closeCustomFile(Object customFile)

createTempDb back to summary

createTempDb	back to summary
protected Database createTempDb(Object customFile, Database.FileFormat format, boolean inMemory, Path tempDir, boolean readOnly) throws IOException Creates a temporary database for holding the table data from linkeeFileName. Parameters customFile:Object custom file state returned from `loadCustomFile` format:Database.FileFormat the access format for the temp db inMemory:boolean whether or not the temp db should be entirely in memory (while this will be faster, it should only be used if table data is expected to fit entirely in memory) tempDir:Path the temp dir for a file based temp db (`null` for the system default temp directory) Returns:Database the temp db for holding the linked table info Annotations @SuppressWarnings:PMD.UseTryWithResources

protected Database createTempDb(Object customFile, Database.FileFormat format, boolean inMemory, Path tempDir, boolean readOnly) throws IOException

Creates a temporary database for holding the table data from linkeeFileName.

Parameters

customFile:Object: custom file state returned from loadCustomFile
format:Database.FileFormat: the access format for the temp db
inMemory:boolean: whether or not the temp db should be entirely in memory (while this will be faster, it should only be used if table data is expected to fit entirely in memory)
tempDir:Path: the temp dir for a file based temp db (null for the system default temp directory)

Returns:Database

the temp db for holding the linked table info

Annotations

@SuppressWarnings:PMD.UseTryWithResources

deleteDbFile	back to summary
private static void deleteDbFile(Path dbFile)

getDefaultFormat	back to summary
protected Database.FileFormat getDefaultFormat()

getDefaultTempDirectory	back to summary
protected Path getDefaultTempDirectory()

isDefaultInMemory	back to summary
protected boolean isDefaultInMemory()

loadCustomFile back to summary

loadCustomFile	back to summary
protected abstract Object loadCustomFile(Database linkerDb, String linkeeFileName) Called by `resolveLinkedDatabase` to determine whether the linkeeFileName should be treated as a custom file (thus utiliziing a temp db) or a normal access db (loaded via the default behavior). Loads any state necessary for subsequently loading data from linkeeFileName. The returned custom file state object will be maintained with the temp db and passed to `loadCustomTable` whenever a new table needs to be loaded. Also, if this object is `Closeable`, it will be closed with the temp db. Parameters linkerDb:Database the primary database in which the link is defined linkeeFileName:String the name of the linked file Returns:Object non-`null` if linkeeFileName should be treated as a custom file (using a temp db) or `null` if it should be treated as a normal access db.

protected abstract Object loadCustomFile(Database linkerDb, String linkeeFileName)

Called by resolveLinkedDatabase to determine whether the linkeeFileName should be treated as a custom file (thus utiliziing a temp db) or a normal access db (loaded via the default behavior). Loads any state necessary for subsequently loading data from linkeeFileName.

The returned custom file state object will be maintained with the temp db and passed to loadCustomTable whenever a new table needs to be loaded. Also, if this object is Closeable, it will be closed with the temp db.

Parameters

linkerDb:Database: the primary database in which the link is defined
linkeeFileName:String: the name of the linked file

Returns:Object

non-null if linkeeFileName should be treated as a custom file (using a temp db) or null if it should be treated as a normal access db.

loadCustomTable back to summary

loadCustomTable	back to summary
protected abstract boolean loadCustomTable(Database tempDb, Object customFile, String tableName) throws IOException Called by an instance of a temp db when a missing table is first requested. Parameters tempDb:Database the temp db instance which should be populated with the relevant table info for the given tableName customFile:Object custom file state returned from `loadCustomFile` tableName:String the name of the table which is requested from the linked file Returns:boolean `true` if the table was available in the linked file, `false` otherwise

protected abstract boolean loadCustomTable(Database tempDb, Object customFile, String tableName) throws IOException

Called by an instance of a temp db when a missing table is first requested.

Parameters

tempDb:Database: the temp db instance which should be populated with the relevant table info for the given tableName
customFile:Object: custom file state returned from loadCustomFile
tableName:String: the name of the table which is requested from the linked file

Returns:boolean

true if the table was available in the linked file, false otherwise

resolveLinkedDatabase back to summary

resolveLinkedDatabase	back to summary
public Database resolveLinkedDatabase(Database linkerDb, String linkeeFileName) throws IOException Implements io.github.spannm.jackcess.util.LinkResolver.resolveLinkedDatabase. Custom implementation is: // attempt to load the linkeeFileName as a custom file Object customFile = loadCustomFile(linkerDb, linkeeFileName); if (customFile != null) { // this is a custom file, create and return relevant temp db return createTempDb(customFile, getDefaultFormat(), isDefaultInMemory(), getDefaultTempDirectory()); } // not a custom file, load using the default behavior return LinkResolver.DEFAULT.resolveLinkedDatabase(linkerDb, linkeeFileName); The fallback behavior denies automatic linked database resolution. The `loadCustomFile` implementation is application-provided and is responsible for validating its own input. Override this method and explicitly delegate to `LinkResolver#UNRESTRICTED` only when linked database paths come from a trusted source. Annotations @Override See Also `loadCustomFile`, `createTempDb`, `LinkResolver#DEFAULT`, `LinkResolver#UNRESTRICTED`

public Database resolveLinkedDatabase(Database linkerDb, String linkeeFileName) throws IOException

Implements io.github.spannm.jackcess.util.LinkResolver.resolveLinkedDatabase.

Custom implementation is:

// attempt to load the linkeeFileName as a custom file
Object customFile = loadCustomFile(linkerDb, linkeeFileName);

if (customFile != null) {
    // this is a custom file, create and return relevant temp db
    return createTempDb(customFile, getDefaultFormat(), isDefaultInMemory(),
        getDefaultTempDirectory());
}

// not a custom file, load using the default behavior
return LinkResolver.DEFAULT.resolveLinkedDatabase(linkerDb, linkeeFileName);

The fallback behavior denies automatic linked database resolution. The loadCustomFile implementation is application-provided and is responsible for validating its own input. Override this method and explicitly delegate to LinkResolver#UNRESTRICTED only when linked database paths come from a trusted source.

Annotations

@Override

io.github.spannm.jackcess.util back to summary

private Class CustomLinkResolver.TempDatabaseImpl

Class Inheritance

extends DatabaseImpl

java.lang.Object
io.github.spannm.jackcess.impl.DatabaseImpl
io.github.spannm.jackcess.util.CustomLinkResolver.TempDatabaseImpl

Subclass of DatabaseImpl which allows us to load tables "on demand" as well as delete the temporary db on close.

Field Summary

Modifier and Type	Field and Description
private final Object	customFile
private final CustomLinkResolver	resolver

Inherited from io.github.spannm.jackcess.impl.DatabaseImpl:: DEFAULT_RESOURCE_PATH HIDDEN_OBJECT_FLAG RO_CHANNEL_OPTS RW_CHANNEL_OPTS RWC_CHANNEL_OPTS

Constructor Summary

Access	Constructor and Description
protected	TempDatabaseImpl(CustomLinkResolver resolver, Object customFile, Path file, FileChannel channel, Database.FileFormat fileFormat, boolean readOnly)

Method Summary

Modifier and Type	Method and Description
public void	close() Overrides io.github.spannm.jackcess.impl.DatabaseImpl.close. Implements io.github.spannm.jackcess.Database.close. Close the database file (and any linked databases).
protected TableImpl	getTable(String name, boolean includeSystemTables) Overrides io.github.spannm.jackcess.impl.DatabaseImpl.getTable. Returns the table, or null if it doesn't exist.
pack-priv static FileChannel	initDbChannel(FileChannel channel, Database.FileFormat format)

Inherited from io.github.spannm.jackcess.impl.DatabaseImpl:: clearTableCache create createDateFormat createLinkedTable createTable createTable flush getAccessControlEntries getCharset getColumnOrder getColumnValidatorFactory getDatabasePassword getDatabaseProperties getDateTimeFactory getDateTimeType getDefaultAllowAutoNumberInsert getDefaultCharset getDefaultCodePage getDefaultColumnOrder getDefaultDateTimeType getDefaultEnforceForeignKeys getDefaultEvaluateExpressions getDefaultSortOrder getDefaultTimeZone getDefaultWriteBrokenIndex getErrorHandler getEvalConfig getFile getFileFormat getFileFormatDetails getFormat getLinkedDatabases getLinkResolver getName getPageChannel getPasswordMask getPath getPropertiesForObject getQueries getRelationships getRelationships getRelationships getRelationships getResourceAsStream getSummaryProperties getSystemCatalog getSystemComplexColumns getSystemRelationships getSystemTable getSystemTableNames getTable getTable getTableMetaData getTableNames getTimeZone getUserDefinedProperties getZoneId isAllowAutoNumberInsert isEnforceForeignKeys isEvaluateExpressions isLinkedTable isReadOnly isWriteBrokenIndex iterator iterator newIterable newTableMetaDataIterable open readProperties setAllowAutoNumberInsert setCharset setColumnOrder setColumnValidatorFactory setDateTimeType setEnforceForeignKeys setErrorHandler setEvaluateExpressions setLinkResolver setTimeZone setWriteBrokenIndex setZoneId toLookupName toString transferDatabase validateIdentifierName validateNewTableName

Field Detail

customFile	back to summary
private final Object customFile

resolver	back to summary
private final CustomLinkResolver resolver

Constructor Detail

TempDatabaseImpl	back to summary
protected TempDatabaseImpl(CustomLinkResolver resolver, Object customFile, Path file, FileChannel channel, Database.FileFormat fileFormat, boolean readOnly) throws IOException

Method Detail

close	back to summary
public void close() throws IOException Overrides io.github.spannm.jackcess.impl.DatabaseImpl.close. Implements io.github.spannm.jackcess.Database.close. Doc from io.github.spannm.jackcess.Database.close. Close the database file (and any linked databases). A Database must be closed after use or changes could be lost and the Database file corrupted. A Database instance should be treated like any other external resource which would be closed in a finally block (e.g. an OutputStream or jdbc Connection). Annotations @Override Exceptions IOException: Doc from java.io.Closeable.close. if an I/O error occurs

back to summary

public void close() throws IOException

Overrides io.github.spannm.jackcess.impl.DatabaseImpl.close.

Implements io.github.spannm.jackcess.Database.close.

Doc from io.github.spannm.jackcess.Database.close.

Close the database file (and any linked databases). A Database must be closed after use or changes could be lost and the Database file corrupted. A Database instance should be treated like any other external resource which would be closed in a finally block (e.g. an OutputStream or jdbc Connection).

Annotations

@Override

Exceptions

IOException:

Doc from java.io.Closeable.close.

if an I/O error occurs

getTable	back to summary
protected TableImpl getTable(String name, boolean includeSystemTables) throws IOException Overrides io.github.spannm.jackcess.impl.DatabaseImpl.getTable. Doc from io.github.spannm.jackcess.impl.DatabaseImpl.getTable. Returns the table, or null if it doesn't exist. Annotations @Override

getTable

back to summary

protected TableImpl getTable(String name, boolean includeSystemTables) throws IOException

Overrides io.github.spannm.jackcess.impl.DatabaseImpl.getTable.

Doc from io.github.spannm.jackcess.impl.DatabaseImpl.getTable.

Returns the table, or null if it doesn't exist.

Annotations