loci.poi.hpsf

Class Property

java.lang.Object

loci.poi.hpsf.Property

Direct Known Subclasses:

MutableProperty

public class Property
extends Object

A property in a Section of a PropertySet.

The property's ID gives the property a meaning in the context of its Section. Each Section spans its own name space of property IDs.

The property's type determines how its value is interpreted. For example, if the type is Variant.VT_LPSTR (byte string), the value consists of a DWord telling how many bytes the string contains. The bytes follow immediately, including any null bytes that terminate the string. The type Variant.VT_I4 denotes a four-byte integer value, Variant.VT_FILETIME some date and time (of a file).

Please note that not all Variant types yet. This might change over time but largely depends on your feedback so that the POI team knows which variant types are really needed. So please feel free to submit error reports or patches for the types you need.

Microsoft documentation: Property Set Display Name Dictionary.

Since:

2002-02-09

Version:

$Id: Property.java 489730 2006-12-22 19:18:16Z bayard $

Author:

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

See Also:

Section, Variant

Field Summary

Fields

Modifier and Type	Field and Description
protected long	id The property's ID.
protected long	type The property's type.
protected Object	value The property's value.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Property() Creates an empty property.
	Property(long id, byte[] src, long offset, int length, int codepage) Creates a Property instance by reading its bytes from the property set stream.
	Property(long id, long type, Object value) Creates a property.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(Object o) Compares two properties.
long	getID() Returns the property's ID.
protected int	getSize() Returns the property's size in bytes.
long	getType() Returns the property's type.
Object	getValue() Returns the property's value.
int	hashCode()
protected Map	readDictionary(byte[] src, long offset, int length, int codepage) Reads a dictionary.
String	toString()
private boolean	typesAreEqual(long t1, long t2)

Methods inherited from class java.lang.Object

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

Field Detail

id

protected long id

The property's ID.

type

protected long type

The property's type.

value

protected Object value

The property's value.

Constructor Detail

Property

public Property(long id,
        long type,
        Object value)

Creates a property.

Parameters:

id - the property's ID.

type - the property's type, see Variant.

value - the property's value. Only certain types are allowed, see Variant.

Property

public Property(long id,
        byte[] src,
        long offset,
        int length,
        int codepage)
         throws UnsupportedEncodingException

Creates a Property instance by reading its bytes from the property set stream.

Parameters:

id - The property's ID.

src - The bytes the property set stream consists of.

offset - The property's type/value pair's offset in the section.

length - The property's type/value pair's length in bytes.

codepage - The section's and thus the property's codepage. It is needed only when reading string values.

Throws:

UnsupportedEncodingException - if the specified codepage is not supported.

Property

protected Property()

Creates an empty property. It must be filled using the set method to be usable.

Method Detail

getID

public long getID()

Returns the property's ID.

Returns:

The ID value

getType

public long getType()

Returns the property's type.

Returns:

The type value

getValue

public Object getValue()

Returns the property's value.

Returns:

The property's value

readDictionary

protected Map readDictionary(byte[] src,
                 long offset,
                 int length,
                 int codepage)
                      throws UnsupportedEncodingException

Reads a dictionary.

Parameters:

src - The byte array containing the bytes making out the dictionary.

offset - At this offset within src the dictionary starts.

length - The dictionary contains at most this many bytes.

codepage - The codepage of the string values.

Returns:

The dictonary

Throws:

UnsupportedEncodingException - if the dictionary's codepage is not (yet) supported.

getSize

protected int getSize()
               throws WritingNotSupportedException

Returns the property's size in bytes. This is always a multiple of 4.

Returns:

the property's size in bytes

Throws:

WritingNotSupportedException - if HPSF does not yet support the property's variant type.

equals

public boolean equals(Object o)

Compares two properties.

Please beware that a property with ID == 0 is a special case: It does not have a type, and its value is the section's dictionary. Another special case are strings: Two properties may have the different types Variant.VT_LPSTR and Variant.VT_LPWSTR;

Overrides:

equals in class Object

See Also:

Object.equals(java.lang.Object)

typesAreEqual

private boolean typesAreEqual(long t1,
                    long t2)

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()