org.geotools.data.vpf.file

Class VPFFile

Object

VPFFile

public class VPFFile
extends Object

This class encapsulates VPF files, serving as a factory for VPFColumns. Instances of this class should be created by VPFFileFactory.

Author:

Jeff Yutzler

Constructor Summary

Constructors

Constructor and Description
VPFFile(String cPathName) Constructor.

Method Summary

Modifier and Type	Method and Description
void	close() Close the input stream pointed to by the object
int	getAttributeCount()
char	getByteOrder() Gets the value of byteOrder variable.
VPFColumn	getColumn(int index)
VPFColumn	getColumn(String name)
int	getColumnCount()
AttributeDescriptor	getDescriptor(String name)
String	getDirectoryName() Returns the directory name for this file by chopping off the file name and the separator.
SimpleFeatureType	getFeatureType()
String	getFileName() Returns the file name (without path) for the file
String	getNarrativeTable() Gets the value of narrativeTable variable file name.
String	getPathName() Gets the full path name for this file
protected int	getRecordSize() Method getRecordSize is used to return size in bytes of records stored in this table.
SimpleFeature	getRowFromId(String idName, int id) Returns a row with a matching value for the provided column
SimpleFeature	getRowFromId0(String idName, int id)
String	getTypeName()
boolean	hasNext() Determines if the stream contains storage for another object.
boolean	isAbstract()
AbstractList<SimpleFeature>	readAllRows() Generates a list containing all of the features in the file
protected char	readChar() Reads a single byte as a character value
protected double	readDouble() Retrieves a double from the file
SimpleFeature	readFeature() Retrieves a feature from the file
protected Object	readFixedSizeData(char dataType, int instancesCount) Retrieves a fixed amount of data from the file
protected float	readFloat() Retrieves a floating point number from the file.
protected Object	readGeometry(int instancesCount, int dimensionality, boolean readDoubles) Constructs an object which is an instance of Geometry by reading values from the file.
protected void	readHeader() Retrieves a number of attributes from the file header
protected int	readInteger() Retrieves an integer value from the file
protected byte[]	readNumber(int cnt) Reads some byte data from the file
protected short	readShort() Retrieves a short value from the file
protected String	readString(String terminators) Reads a string value from the file
protected TripletId	readTripletId() Retrieves a triplet object from the file
protected Object	readVariableSizeData(char dataType) Retrieves variable sized data from the file by first reading an integer which indicates how many instances of the data type to retrieve
void	reset() Resets the file stream by setting its pointer to the first position after the header.
protected void	setPosition(long pos) Sets the position in the stream
String	toString()
protected void	unread(long bytes) Back up a specified number of bytes in the file stream

Methods inherited from class Object

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

Constructor Detail

VPFFile

public VPFFile(String cPathName)
        throws IOException,
               SchemaException

Constructor.

Parameters:

cPathName - The path to this file

Throws:

IOException - if the path or the file are invalid

SchemaException - if the contained feature type can not be constructed

Method Detail

getFeatureType

public SimpleFeatureType getFeatureType()

getAttributeCount

public int getAttributeCount()

getByteOrder

public char getByteOrder()

Gets the value of byteOrder variable. Byte order in which table is written:

• L - least-significant-first
• M - most-significant-first

Returns:

the value of byteOrder

getDirectoryName

public String getDirectoryName()

Returns the directory name for this file by chopping off the file name and the separator.

Returns:

the directory name for this file

getFileName

public String getFileName()

Returns the file name (without path) for the file

Returns:

the file name for this file

getNarrativeTable

public String getNarrativeTable()

Gets the value of narrativeTable variable file name.

Returns:

the value of narrativeTable

getPathName

public String getPathName()

Gets the full path name for this file

Returns:

the path name for this file

getRecordSize

protected int getRecordSize()

Method getRecordSize is used to return size in bytes of records stored in this table. If table keeps variable length records -1 should be returned.

Returns:

an int value

getRowFromId

public SimpleFeature getRowFromId(String idName,
                                  int id)

Returns a row with a matching value for the provided column

Parameters:

idName - The name of the column to look for, such as "id"

id - An identifier for the requested row

Returns:

The first row which matches the ID

Throws:

IllegalAttributeException - The feature can not be created due to illegal attributes in the source file

getRowFromId0

public SimpleFeature getRowFromId0(String idName,
                                   int id)

getTypeName

public String getTypeName()

hasNext

public boolean hasNext()

Determines if the stream contains storage for another object. Who knows how well this will work on variable length objects?

Returns:

a boolean

isAbstract

public boolean isAbstract()

readAllRows

public AbstractList<SimpleFeature> readAllRows()
                                        throws IOException

Generates a list containing all of the features in the file

Returns:

a List value containing Feature objects

Throws:

IOException - if an error occurs

readChar

protected char readChar()
                 throws IOException

Reads a single byte as a character value

Returns:

a char value

Throws:

IOException - if an error occurs

readGeometry

protected Object readGeometry(int instancesCount,
                              int dimensionality,
                              boolean readDoubles)
                       throws IOException

Constructs an object which is an instance of Geometry by reading values from the file.

Parameters:

instancesCount - number of coordinates to read

dimensionality - either 2 or 3

readDoubles - true: read a double value; false: read a float value

Returns:

the constructed object

Throws:

IOException - on any file IO errors

readDouble

protected double readDouble()
                     throws IOException

Retrieves a double from the file

Returns:

a double value

Throws:

IOException - if an error occurs

readFeature

public SimpleFeature readFeature()
                          throws IOException,
                                 IllegalAttributeException

Retrieves a feature from the file

Returns:

the retieved feature

Throws:

IOException - on any file IO errors

IllegalAttributeException - if any of the attributes retrieved are illegal

readFixedSizeData

protected Object readFixedSizeData(char dataType,
                                   int instancesCount)
                            throws IOException

Retrieves a fixed amount of data from the file

Parameters:

dataType - a char value indicating the data type

instancesCount - an int value indicating the number of instances to retrieve.

Returns:

an Object value

Throws:

IOException - if an error occurs

readFloat

protected float readFloat()
                   throws IOException

Retrieves a floating point number from the file.

Returns:

a float value

Throws:

IOException - if an error occurs

readHeader

protected void readHeader()
                   throws VPFHeaderFormatException,
                          IOException

Retrieves a number of attributes from the file header

Throws:

VPFHeaderFormatException - if an error occurs

IOException - if an error occurs

readInteger

protected int readInteger()
                   throws IOException

Retrieves an integer value from the file

Returns:

an int value

Throws:

IOException - if an error occurs

readNumber

protected byte[] readNumber(int cnt)
                     throws IOException

Reads some byte data from the file

Parameters:

cnt - an int value indicating the number of bytes to retrieve

Returns:

a byte[] value

Throws:

IOException - if an error occurs

readShort

protected short readShort()
                   throws IOException

Retrieves a short value from the file

Returns:

a short value

Throws:

IOException - if an error occurs

readString

protected String readString(String terminators)
                     throws IOException

Reads a string value from the file

Parameters:

terminators - a String value indicating the terminators to look for

Returns:

a String value

Throws:

IOException - if an error occurs

readTripletId

protected TripletId readTripletId()
                           throws IOException

Retrieves a triplet object from the file

Returns:

a TripletId value

Throws:

IOException - on any IO errors

readVariableSizeData

protected Object readVariableSizeData(char dataType)
                               throws IOException

Retrieves variable sized data from the file by first reading an integer which indicates how many instances of the data type to retrieve

Parameters:

dataType - a char value indicating the data type

Returns:

an Object value

Throws:

IOException - if an error occurs

reset

public void reset()

Resets the file stream by setting its pointer to the first position after the header.

close

public void close()
           throws IOException

Close the input stream pointed to by the object

Throws:

IOException - in some unlikely situation

setPosition

protected void setPosition(long pos)
                    throws IOException

Sets the position in the stream

Parameters:

pos - A 1-indexed position

Throws:

IOException - on any IO failures

toString

public String toString()

Overrides:

toString in class Object

unread

protected void unread(long bytes)
               throws IOException

Back up a specified number of bytes in the file stream

Parameters:

bytes - a long value

Throws:

IOException - if an error occurs

getColumn

public VPFColumn getColumn(int index)

getColumnCount

public int getColumnCount()

getColumn

public VPFColumn getColumn(String name)

getDescriptor

public AttributeDescriptor getDescriptor(String name)