loci.poi.hpsf

Class Section

java.lang.Object

loci.poi.hpsf.Section

Direct Known Subclasses:

MutableSection

public class Section
extends Object

Represents a section in a PropertySet.

Since:

2002-02-09

Version:

$Id: Section.java 550021 2007-06-23 07:44:47Z klute $

Author:

Rainer Klute <klute@rainer-klute.de>, Drew Varner (Drew.Varner allUpIn sc.edu)

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
(package private) class	Section.PropertyListEntry Represents an entry in the property list and holds a property's ID and its offset from the section's beginning.

Field Summary

Fields

Modifier and Type	Field and Description
protected Map	dictionary Maps property IDs to section-private PID strings.
protected ClassID	formatID The section's format ID, getFormatID().
protected long	offset
protected Property[]	properties
protected int	size
private boolean	wasNull This member is true if the last call to getPropertyIntValue(long) or getProperty(long) tried to access a property that was not available, else false.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Section() Creates an empty and uninitialized Section.
	Section(byte[] src, int offset) Creates a Section instance from a byte array.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(Object o) Checks whether this section is equal to another object.
int	getCodepage() Gets the section's codepage, if any.
Map	getDictionary() Gets the section's dictionary.
ClassID	getFormatID() Returns the format ID.
long	getOffset() Returns the offset of the section in the stream.
String	getPIDString(long pid) Returns the PID string associated with a property ID.
Property[]	getProperties() Returns this section's properties.
Object	getProperty(long id) Returns the value of the property with the specified ID.
protected boolean	getPropertyBooleanValue(int id) Returns the value of the boolean property with the specified ID.
int	getPropertyCount() Returns the number of properties in this section.
protected int	getPropertyIntValue(long id) Returns the value of the numeric property with the specified ID.
int	getSize() Returns the section's size in bytes.
int	hashCode()
private Property[]	remove(Property[] pa, int i) Removes a field from a property array.
String	toString()
boolean	wasNull() Checks whether the property which the last call to getPropertyIntValue(long) or getProperty(long) tried to access was available or not.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

dictionary

protected Map dictionary

Maps property IDs to section-private PID strings. These strings can be found in the property with ID 0.

formatID

protected ClassID formatID

The section's format ID, getFormatID().

offset

protected long offset

See Also:

getOffset()

size

protected int size

See Also:

getSize()

properties

protected Property[] properties

See Also:

getProperties()

wasNull

private boolean wasNull

This member is true if the last call to getPropertyIntValue(long) or getProperty(long) tried to access a property that was not available, else false.

Constructor Detail

Section

protected Section()

Creates an empty and uninitialized Section.

Section

public Section(byte[] src,
       int offset)
        throws UnsupportedEncodingException

Creates a Section instance from a byte array.

Parameters:

src - Contains the complete property set stream.

offset - The position in the stream that points to the section's format ID.

Throws:

UnsupportedEncodingException - if the section's codepage is not supported.

Method Detail

getFormatID

public ClassID getFormatID()

Returns the format ID. The format ID is the "type" of the section. For example, if the format ID of the first Section contains the bytes specified by loci.poi.hpsf.wellknown.SectionIDMap.SUMMARY_INFORMATION_ID the section (and thus the property set) is a SummaryInformation.

Returns:

The format ID

getOffset

public long getOffset()

Returns the offset of the section in the stream.

Returns:

The offset of the section in the stream.

getSize

public int getSize()

Returns the section's size in bytes.

Returns:

The section's size in bytes.

getPropertyCount

public int getPropertyCount()

Returns the number of properties in this section.

Returns:

The number of properties in this section.

getProperties

public Property[] getProperties()

Returns this section's properties.

Returns:

This section's properties.

getProperty

public Object getProperty(long id)

Returns the value of the property with the specified ID. If the property is not available, null is returned and a subsequent call to wasNull will return true.

Parameters:

id - The property's ID

Returns:

The property's value

getPropertyIntValue

protected int getPropertyIntValue(long id)

Returns the value of the numeric property with the specified ID. If the property is not available, 0 is returned. A subsequent call to wasNull will return true to let the caller distinguish that case from a real property value of 0.

Parameters:

id - The property's ID

Returns:

The property's value

getPropertyBooleanValue

protected boolean getPropertyBooleanValue(int id)

Returns the value of the boolean property with the specified ID. If the property is not available, false is returned. A subsequent call to wasNull will return true to let the caller distinguish that case from a real property value of false.

Parameters:

id - The property's ID

Returns:

The property's value

wasNull

public boolean wasNull()

Checks whether the property which the last call to getPropertyIntValue(long) or getProperty(long) tried to access was available or not. This information might be important for callers of getPropertyIntValue(long) since the latter returns 0 if the property does not exist. Using wasNull the caller can distiguish this case from a property's real value of 0.

Returns:

true if the last call to getPropertyIntValue(long) or getProperty(long) tried to access a property that was not available, else false.

getPIDString

public String getPIDString(long pid)

Returns the PID string associated with a property ID. The ID is first looked up in the Section's private dictionary. If it is not found there, the method calls SectionIDMap.getPIDString(byte[], long).

Parameters:

pid - The property ID

Returns:

The property ID's string value

equals

public boolean equals(Object o)

Checks whether this section is equal to another object. The result is false if one of the the following conditions holds:

• The other object is not a Section.

• The format IDs of the two sections are not equal.

• The sections have a different number of properties. However, properties with ID 1 (codepage) are not counted.

• The other object is not a Section.

• The properties have different values. The order of the properties is irrelevant.

Overrides:

equals in class Object

Parameters:

o - The object to compare this section with

Returns:

true if the objects are equal, false if not

remove

private Property[] remove(Property[] pa,
                int i)

Removes a field from a property array. The resulting array is compactified and returned.

Parameters:

pa - The property array.

i - The index of the field to be removed.

Returns:

the compactified array.

hashCode

public int hashCode()

Overrides:

hashCode in class Object

See Also:

Object.hashCode()

toString

public String toString()

Overrides:

toString in class Object

See Also:

Object.toString()

getDictionary

public Map getDictionary()

Gets the section's dictionary. A dictionary allows an application to use human-readable property names instead of numeric property IDs. It contains mappings from property IDs to their associated string values. The dictionary is stored as the property with ID 0. The codepage for the strings in the dictionary is defined by property with ID 1.

Returns:

the dictionary or null if the section does not have a dictionary.

getCodepage

public int getCodepage()

Gets the section's codepage, if any.

Returns:

The section's codepage if one is defined, else -1.