com.drew.metadata
Class Directory

java.lang.Object
  com.drew.metadata.Directory

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

CanonMakernoteDirectory, CasioType1MakernoteDirectory, CasioType2MakernoteDirectory, ExifDirectory, ExifInteropDirectory, FujifilmMakernoteDirectory, GpsDirectory, IptcDirectory, JpegCommentDirectory, JpegDirectory, KodakMakernoteDirectory, KyoceraMakernoteDirectory, MockDirectory, NikonType1MakernoteDirectory, NikonType2MakernoteDirectory, OlympusMakernoteDirectory, PanasonicMakernoteDirectory, PentaxMakernoteDirectory, SonyMakernoteDirectory

public abstract class Directory
extends Object
implements Serializable

Abstract base class for all directory implementations, having methods for getting and setting tag values of various data types.

See Also:

Serialized Form

Field Summary

protected List	_definedTagList A convenient list holding tag values in the order in which they were stored.
protected TagDescriptor	_descriptor The descriptor used to interperet tag values.
private List	_errorList
protected HashMap	_tagMap Map of values hashed by type identifiers.

Constructor Summary

Directory()
Creates a new Directory.

Method Summary

void	addError(String message) Registers an error message with this directory.
boolean	containsTag(int tagType) Indicates whether the specified tag type has been set.
boolean	getBoolean(int tagType) Returns the specified tag's value as a boolean, if possible.
byte[]	getByteArray(int tagType) Gets the specified tag's value as an byte array, if possible.
Date	getDate(int tagType) Returns the specified tag's value as a java.util.Date, if possible.
String	getDescription(int tagType) Provides a description of a tag's value using the descriptor set by setDescriptor(Descriptor).
double	getDouble(int tagType) Returns the specified tag's value as a double, if possible.
int	getErrorCount() Returns the count of error messages in this directory.
Iterator	getErrors() Used to iterate over any error messages contained in this directory.
float	getFloat(int tagType) Returns the specified tag's value as a float, if possible.
int	getInt(int tagType) Returns the specified tag's value as an int, if possible.
int[]	getIntArray(int tagType) Gets the specified tag's value as an int array, if possible.
long	getLong(int tagType) Returns the specified tag's value as a long, if possible.
abstract String	getName() Provides the name of the directory, for display purposes.
Object	getObject(int tagType) Returns the object hashed for the particular tag type specified, if available.
Rational	getRational(int tagType) Returns the specified tag's value as a Rational, if possible.
Rational[]	getRationalArray(int tagType)
String	getString(int tagType) Returns the specified tag's value as a String.
String[]	getStringArray(int tagType) Gets the specified tag's value as a String array, if possible.
int	getTagCount() Returns the number of tags set in this Directory.
Iterator	getTagIterator() Returns an Iterator of Tag instances that have been set in this Directory.
String	getTagName(int tagType) Returns the name of a specified tag as a String.
protected abstract HashMap	getTagNameMap() Provides the map of tag names, hashed by tag type identifier.
boolean	hasErrors() Gets a value indicating whether this directory has any error messages.
void	setBoolean(int tagType, boolean value) Sets a boolean value for the specified tag.
void	setByteArray(int tagType, byte[] bytes) Sets a byte[] (array) for the specified tag.
void	setDate(int tagType, Date value) Sets a java.util.Date value for the specified tag.
void	setDescriptor(TagDescriptor descriptor) Sets the descriptor used to interperet tag values.
void	setDouble(int tagType, double value) Sets a double value for the specified tag.
void	setFloat(int tagType, float value) Sets a float value for the specified tag.
void	setInt(int tagType, int value) Sets an int value for the specified tag.
void	setIntArray(int tagType, int[] ints) Sets an int[] (array) for the specified tag.
void	setLong(int tagType, long value) Sets a long value for the specified tag.
void	setObject(int tagType, Object value) Sets a Object for the specified tag.
void	setObjectArray(int tagType, Object array) Sets an array Object for the specified tag.
void	setRational(int tagType, Rational rational) Sets a Rational value for the specified tag.
void	setRationalArray(int tagType, Rational[] rationals) Sets a Rational[] (array) for the specified tag.
void	setString(int tagType, String value) Sets a String value for the specified tag.
void	setStringArray(int tagType, String[] strings) Sets a String[] (array) for the specified tag.

Methods inherited from class java.lang.Object

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

Field Detail

_tagMap

protected final HashMap _tagMap

Map of values hashed by type identifiers.

_descriptor

protected TagDescriptor _descriptor

The descriptor used to interperet tag values.

_definedTagList

protected final List _definedTagList

A convenient list holding tag values in the order in which they were stored. This is used for creation of an iterator, and for counting the number of defined tags.

_errorList

private List _errorList

Constructor Detail

Directory

public Directory()

Creates a new Directory.

Method Detail

getName

public abstract String getName()

Provides the name of the directory, for display purposes. E.g. Exif

Returns:

the name of the directory

getTagNameMap

protected abstract HashMap getTagNameMap()

Provides the map of tag names, hashed by tag type identifier.

Returns:

the map of tag names

containsTag

public boolean containsTag(int tagType)

Indicates whether the specified tag type has been set.

Parameters:

tagType - the tag type to check for

Returns:

true if a value exists for the specified tag type, false if not

getTagIterator

public Iterator getTagIterator()

Returns an Iterator of Tag instances that have been set in this Directory.

Returns:

an Iterator of Tag instances

getTagCount

public int getTagCount()

Returns the number of tags set in this Directory.

Returns:

the number of tags set in this Directory

setDescriptor

public void setDescriptor(TagDescriptor descriptor)

Sets the descriptor used to interperet tag values.

Parameters:

descriptor - the descriptor used to interperet tag values

addError

public void addError(String message)

Registers an error message with this directory.

Parameters:

message - an error message.

hasErrors

public boolean hasErrors()

Gets a value indicating whether this directory has any error messages.

Returns:

true if the directory contains errors, otherwise false

getErrors

public Iterator getErrors()

Used to iterate over any error messages contained in this directory.

Returns:

an iterator over the error message strings.

getErrorCount

public int getErrorCount()

Returns the count of error messages in this directory.

setInt

public void setInt(int tagType,
                   int value)

Sets an int value for the specified tag.

Parameters:

tagType - the tag's value as an int

value - the value for the specified tag as an int

setDouble

public void setDouble(int tagType,
                      double value)

Sets a double value for the specified tag.

Parameters:

tagType - the tag's value as an int

value - the value for the specified tag as a double

setFloat

public void setFloat(int tagType,
                     float value)

Sets a float value for the specified tag.

Parameters:

tagType - the tag's value as an int

value - the value for the specified tag as a float

setString

public void setString(int tagType,
                      String value)

Sets a String value for the specified tag.

Parameters:

tagType - the tag's value as an int

value - the value for the specified tag as a String

setBoolean

public void setBoolean(int tagType,
                       boolean value)

Sets a boolean value for the specified tag.

Parameters:

tagType - the tag's value as an int

value - the value for the specified tag as a boolean

setLong

public void setLong(int tagType,
                    long value)

Sets a long value for the specified tag.

Parameters:

tagType - the tag's value as an int

value - the value for the specified tag as a long

setDate

public void setDate(int tagType,
                    Date value)

Sets a java.util.Date value for the specified tag.

Parameters:

tagType - the tag's value as an int

value - the value for the specified tag as a java.util.Date

setRational

public void setRational(int tagType,
                        Rational rational)

Sets a Rational value for the specified tag.

Parameters:

tagType - the tag's value as an int

rational - rational number

setRationalArray

public void setRationalArray(int tagType,
                             Rational[] rationals)

Sets a Rational[] (array) for the specified tag.

Parameters:

tagType - the tag identifier

rationals - the Rational array to store

setIntArray

public void setIntArray(int tagType,
                        int[] ints)

Sets an int[] (array) for the specified tag.

Parameters:

tagType - the tag identifier

ints - the int array to store

setByteArray

public void setByteArray(int tagType,
                         byte[] bytes)

Sets a byte[] (array) for the specified tag.

Parameters:

tagType - the tag identifier

bytes - the byte array to store

setStringArray

public void setStringArray(int tagType,
                           String[] strings)

Sets a String[] (array) for the specified tag.

Parameters:

tagType - the tag identifier

strings - the String array to store

setObject

public void setObject(int tagType,
                      Object value)

Sets a Object for the specified tag.

Parameters:

tagType - the tag's value as an int

value - the value for the specified tag

Throws:

NullPointerException - if value is null

setObjectArray

public void setObjectArray(int tagType,
                           Object array)

Sets an array Object for the specified tag.

Parameters:

tagType - the tag's value as an int

array - the array of values for the specified tag

getInt

public int getInt(int tagType)
           throws MetadataException

Returns the specified tag's value as an int, if possible. Every attempt to represent the tag's value as an int is taken. Here is a list of the action taken depending upon the tag's original type:

• int - Return unchanged.
• Number - Return an int value (real numbers are truncated).
• Rational - Truncate any fractional part and returns remaining int.
• String - Attempt to parse string as an int. If this fails, convert the char[] to an int (using shifts and OR).
• Rational[] - Return int value of first item in array.
• byte[] - Return int value of first item in array.
• int[] - Return int value of first item in array.

Throws:

MetadataException - if no value exists for tagType or if it cannot be cast to an int.

getStringArray

public String[] getStringArray(int tagType)
                        throws MetadataException

Gets the specified tag's value as a String array, if possible. Only supported where the tag is set as String[], String, int[], byte[] or Rational[].

Parameters:

tagType - the tag identifier

Returns:

the tag's value as an array of Strings

Throws:

MetadataException - if the tag has not been set or cannot be represented as a String[]

getIntArray

public int[] getIntArray(int tagType)
                  throws MetadataException

Gets the specified tag's value as an int array, if possible. Only supported where the tag is set as String, int[], byte[] or Rational[].

Parameters:

tagType - the tag identifier

Returns:

the tag's value as an int array

Throws:

MetadataException - if the tag has not been set, or cannot be converted to an int array

getByteArray

public byte[] getByteArray(int tagType)
                    throws MetadataException

Gets the specified tag's value as an byte array, if possible. Only supported where the tag is set as String, int[], byte[] or Rational[].

Parameters:

tagType - the tag identifier

Returns:

the tag's value as a byte array

Throws:

MetadataException - if the tag has not been set, or cannot be converted to a byte array

getDouble

public double getDouble(int tagType)
                 throws MetadataException

Returns the specified tag's value as a double, if possible.

Throws:

MetadataException

getFloat

public float getFloat(int tagType)
               throws MetadataException

Returns the specified tag's value as a float, if possible.

Throws:

MetadataException

getLong

public long getLong(int tagType)
             throws MetadataException

Returns the specified tag's value as a long, if possible.

Throws:

MetadataException

getBoolean

public boolean getBoolean(int tagType)
                   throws MetadataException

Returns the specified tag's value as a boolean, if possible.

Throws:

MetadataException

getDate

public Date getDate(int tagType)
             throws MetadataException

Returns the specified tag's value as a java.util.Date, if possible.

Throws:

MetadataException

getRational

public Rational getRational(int tagType)
                     throws MetadataException

Returns the specified tag's value as a Rational, if possible.

Throws:

MetadataException

getRationalArray

public Rational[] getRationalArray(int tagType)
                            throws MetadataException

Throws:

MetadataException

getString

public String getString(int tagType)

Returns the specified tag's value as a String. This value is the 'raw' value. A more presentable decoding of this value may be obtained from the corresponding Descriptor.

Returns:

the String reprensentation of the tag's value, or null if the tag hasn't been defined.

getObject

public Object getObject(int tagType)

Returns the object hashed for the particular tag type specified, if available.

Parameters:

tagType - the tag type identifier

Returns:

the tag's value as an Object if available, else null

getTagName

public String getTagName(int tagType)

Returns the name of a specified tag as a String.

Parameters:

tagType - the tag type identifier

Returns:

the tag's name as a String

getDescription

public String getDescription(int tagType)
                      throws MetadataException

Provides a description of a tag's value using the descriptor set by setDescriptor(Descriptor).

Parameters:

tagType - the tag type identifier

Returns:

the tag value's description as a String

Throws:

MetadataException - if a descriptor hasn't been set, or if an error occurs during calculation of the description within the Descriptor