org.apache.poi.hpsf
Class Property

java.lang.Object
  org.apache.poi.hpsf.Property

Direct Known Subclasses:

MutableProperty

public class Property
extends java.lang.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.

Author:

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

See Also:

Section, Variant

Field Summary

protected long	id The property's ID.
protected long	type The property's type.
protected java.lang.Object	value The property's value.

Constructor Summary

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, java.lang.Object value) Creates a property.

Method Summary

boolean	equals(java.lang.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.
java.lang.Object	getValue() Returns the property's value.
int	hashCode()
protected java.util.Map<?,?>	readDictionary(byte[] src, long offset, int length, int codepage) Reads a dictionary.
java.lang.String	toString()

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 java.lang.Object value

The property's value.

Constructor Detail

Property

public Property(long id,
                long type,
                java.lang.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 java.io.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:

java.io.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 java.lang.Object getValue()

Returns the property's value.

Returns:

The property's value

readDictionary

protected java.util.Map<?,?> readDictionary(byte[] src,
                                            long offset,
                                            int length,
                                            int codepage)
                                     throws java.io.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:

java.io.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(java.lang.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 java.lang.Object

See Also:

Object.equals(java.lang.Object)

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

See Also:

Object.hashCode()

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

See Also:

Object.toString()