com.graphhopper.storage

Class AbstractDataAccess

java.lang.Object

com.graphhopper.storage.AbstractDataAccess

All Implemented Interfaces:

DataAccess, Storable<DataAccess>, Closeable, AutoCloseable

Direct Known Subclasses:

MMapDataAccess, RAMDataAccess, UnsafeDataAccess

public abstract class AbstractDataAccess
extends Object
implements DataAccess

Author:

Peter Karich

Field Summary

Fields

Modifier and Type	Field and Description
protected BitUtil	bitUtil
protected ByteOrder	byteOrder
protected boolean	closed
protected static byte[]	EMPTY
protected int[]	header
protected static int	HEADER_OFFSET
protected int	indexDivisor
protected String	name
protected static int	SEGMENT_SIZE_MIN
protected int	segmentSizeInBytes
protected int	segmentSizePower

Constructor Summary

Constructors

Constructor and Description
AbstractDataAccess(String name, String location, ByteOrder order)

Method Summary

Modifier and Type	Method and Description
protected boolean	checkBeforeRename(String newName)
void	close() This method makes sure that the underlying used resources are released.
protected void	copyHeader(DataAccess da)
DataAccess	copyTo(DataAccess da) Copies the content from this object into the specified one.
protected String	getFullName()
int	getHeader(int bytePos) Get 4 bytes from the header at 'index'
String	getName() The logical identification of this object.
int	getSegmentSize()
boolean	isClosed()
protected boolean	isIntBased()
boolean	isStoring()
protected long	readHeader(RandomAccessFile raFile)
void	rename(String newName) Renames the underlying DataAccess object.
void	setHeader(int bytePos, int value) Set 4 bytes at the header space index to the specified value
DataAccess	setSegmentSize(int bytes) In order to increase allocated space one needs to layout the underlying storage in segments.
String	toString()
protected void	writeHeader(RandomAccessFile file, long length, int segmentSize) Writes some internal data into the beginning of the specified file.

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.graphhopper.storage.DataAccess

create, ensureCapacity, getBytes, getInt, getSegments, getShort, getType, setBytes, setInt, setShort, trimTo

Methods inherited from interface com.graphhopper.storage.Storable

flush, getCapacity, loadExisting

Field Detail

SEGMENT_SIZE_MIN

protected static final int SEGMENT_SIZE_MIN

See Also:

Constant Field Values

HEADER_OFFSET

protected static final int HEADER_OFFSET

See Also:

Constant Field Values

EMPTY

protected static final byte[] EMPTY

byteOrder

protected final ByteOrder byteOrder

bitUtil

protected final BitUtil bitUtil

header

protected int[] header

name

protected String name

segmentSizeInBytes

protected int segmentSizeInBytes

segmentSizePower

protected int segmentSizePower

indexDivisor

protected int indexDivisor

closed

protected boolean closed

Constructor Detail

AbstractDataAccess

public AbstractDataAccess(String name,
                          String location,
                          ByteOrder order)

Method Detail

getName

public String getName()

Description copied from interface: DataAccess

The logical identification of this object.

Specified by:

getName in interface DataAccess

getFullName

protected String getFullName()

close

public void close()

Description copied from interface: Storable

This method makes sure that the underlying used resources are released. WARNING: it does NOT flush on close!

Specified by:

close in interface Storable<DataAccess>

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

isClosed

public boolean isClosed()

Specified by:

isClosed in interface Storable<DataAccess>

setHeader

public void setHeader(int bytePos,
                      int value)

Description copied from interface: DataAccess

Set 4 bytes at the header space index to the specified value

Specified by:

setHeader in interface DataAccess

getHeader

public int getHeader(int bytePos)

Description copied from interface: DataAccess

Get 4 bytes from the header at 'index'

Specified by:

getHeader in interface DataAccess

writeHeader

protected void writeHeader(RandomAccessFile file,
                           long length,
                           int segmentSize)
                    throws IOException

Writes some internal data into the beginning of the specified file.

Throws:

IOException

readHeader

protected long readHeader(RandomAccessFile raFile)
                   throws IOException

Throws:

IOException

copyHeader

protected void copyHeader(DataAccess da)

copyTo

public DataAccess copyTo(DataAccess da)

Description copied from interface: DataAccess

Copies the content from this object into the specified one.

Specified by:

copyTo in interface DataAccess

setSegmentSize

public DataAccess setSegmentSize(int bytes)

Description copied from interface: DataAccess

In order to increase allocated space one needs to layout the underlying storage in segments. This is how you can customize the size.

Specified by:

setSegmentSize in interface DataAccess

getSegmentSize

public int getSegmentSize()

Specified by:

getSegmentSize in interface DataAccess

Returns:

the size of one segment in bytes

toString

public String toString()

Overrides:

toString in class Object

rename

public void rename(String newName)

Description copied from interface: DataAccess

Renames the underlying DataAccess object. (Flushing shouldn't be necessary before or afterwards)

Specified by:

rename in interface DataAccess

checkBeforeRename

protected boolean checkBeforeRename(String newName)

isStoring

public boolean isStoring()

isIntBased

protected boolean isIntBased()