oracle.ifs.server

Class S_RandomAccessorImpl

java.lang.Object

oracle.ifs.server.S_RandomAccessorImpl

All Implemented Interfaces:

RandomAccessor

public class S_RandomAccessorImpl
extends Object
implements RandomAccessor

RandomAccessorImpl is the serverside implementation of RandomAccessor.

(Unpublished)

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	S_RandomAccessorImpl(S_Document doc, S_ContentObject co) Constructs a non-writeable (read-only) S_RandomAccessorImpl.
protected	S_RandomAccessorImpl(S_Document doc, S_ContentObject co, S_LibraryObjectDefinition docdef, long expirationPeriod) Constructs a writeable S_RandomAccessorImpl.

Method Summary

Modifier and Type	Method and Description
void	close() Closes this RandomAccessor, saving any changes to the document.
void	dispose() Disposes this RandomAccessor, discarding any changes to the document.
Long	getContentObjectId() Gets the id of the ContentObject being accessed by this RandomAccessor.
Long	getDocumentId() Gets the id of the Document being accessed by this RandomAccessor.
LibrarySessionInterface	getSession() Gets the session associated with this RandomAccessor.
boolean	isWriteable() Gets whether this RandomAccessor is writeable.
long	length() Gets the content length.
int	read(long pos, byte[] b, int off, int len) Reads bytes from content into a byte array.
protected void	setContext(S_LibrarySession session, Transaction transaction) Called by DMRandomAccessor* methods to record the session and transaction context.
void	setSession(LibrarySessionInterface session) Sets the session associated with this RandomAccessor.
String	toString()
void	truncate(long len) Truncates the content to exactly len bytes in length.
void	write(long pos, byte[] b, int off, int len) Writes bytes from a byte array.

Methods inherited from class java.lang.Object

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

Constructor Detail

S_RandomAccessorImpl

protected S_RandomAccessorImpl(S_Document doc,
                               S_ContentObject co)
                        throws IfsException

Constructs a non-writeable (read-only) S_RandomAccessorImpl.

Parameters:

doc - the document

co - the existing ContentObject

Throws:

IfsException

(Unpublished)

S_RandomAccessorImpl

protected S_RandomAccessorImpl(S_Document doc,
                               S_ContentObject co,
                               S_LibraryObjectDefinition docdef,
                               long expirationPeriod)
                        throws IfsException

Constructs a writeable S_RandomAccessorImpl.

Parameters:

doc - the document

co - the existing ContentObject

docdef - the definition used to update the document

expirationPeriod - the expiration period of this S_RandomAccessorImpl in milliseconds

Throws:

IfsException - if the operation fails

(Unpublished)

Method Detail

getDocumentId

public Long getDocumentId()
                   throws IfsException

Gets the id of the Document being accessed by this RandomAccessor.

Specified by:

getDocumentId in interface RandomAccessor

Returns:

the Document id

Throws:

IfsException - if the operation fails

getContentObjectId

public Long getContentObjectId()
                        throws IfsException

Gets the id of the ContentObject being accessed by this RandomAccessor.

Specified by:

getContentObjectId in interface RandomAccessor

Returns:

the ContentObject id

Throws:

IfsException - if the operation fails

setSession

public void setSession(LibrarySessionInterface session)
                throws IfsException

Sets the session associated with this RandomAccessor.

A RandomAccessor is initially bound to the session in which it was created. Call this method to safely use the RandomAccessor in the context of a different session.

Specified by:

setSession in interface RandomAccessor

Parameters:

session - the session

Throws:

IfsException - if the operation fails

getSession

public LibrarySessionInterface getSession()
                                   throws IfsException

Gets the session associated with this RandomAccessor.

Specified by:

getSession in interface RandomAccessor

Returns:

the session

Throws:

IfsException - if the operation fails

read

public int read(long pos,
                byte[] b,
                int off,
                int len)
         throws IfsException

Reads bytes from content into a byte array.

Reads from position pos in content, where 0 is the first byte in content, 1 is the second byte, and so forth.

Attempts to read as many as len bytes, but a smaller number of bytes may actually be read. Returns 0 if len is 0. Otherwise, blocks until at least one byte is read, the end of file is detected, or an error occurs. Returns the number of bytes actually read.

The bytes are read into b starting at index off. If r is the number of bytes actually read (as returned by the method), the bytes are read into elements b[off] through b[off+r-1]. Elements b[off+r] through b[off+len-1] are not changed. Additionally, elements b[0] through b[off-1] are never changed. Similarly, b[off+len] through b[b.length-1] are never changed.

An exception is thrown upon any of the following conditions:

• pos < 0
• pos >= length()
• b == null
• off < 0
• len < 0
• off + len > b.length

Specified by:

read in interface RandomAccessor

Parameters:

pos - the position in content from which to read

b - the buffer into which to read

off - the offset in the buffer

len - the maximum number of bytes to read

Returns:

the actual number of bytes read

Throws:

IfsException - if the operation fails

isWriteable

public boolean isWriteable()
                    throws IfsException

Gets whether this RandomAccessor is writeable.

Specified by:

isWriteable in interface RandomAccessor

Returns:

whether writeable

Throws:

IfsException - if the operation fails

write

public void write(long pos,
                  byte[] b,
                  int off,
                  int len)
           throws IfsException

Writes bytes from a byte array.

If len is 0, the content is unchanged. Otherwise, the content is changed as specified in the following two paragraphs.

The bytes b[off] through b[off+len-1] are written to positions pos through pos + len - 1 in the content, where 0 is the position of the first byte in content, 1 is the second byte, and so forth.

If, prior to the call, pos + len > length(), the method will extend the content so that pos + len == length().

An exception is thrown upon any of the following conditions:

• pos < 0
• b == null
• off < 0
• len < 0
• off + len > b.length
• this RandomAccessor is not writeable

Specified by:

write in interface RandomAccessor

Parameters:

pos - the position in content from which to write

b - the buffer from which to write

off - the offset in the buffer

len - the number of bytes to write

Throws:

IfsException - if the operation fails

truncate

public void truncate(long len)
              throws IfsException

Truncates the content to exactly len bytes in length.

If len > length(), the content at byte positions len through length() - 1 are dropped, where 0 is the position of the first byte in content, 1 the second byte, and so forth.

If len < length(), the content is resized by zero-filling positions length() through len - 1.

If len == length(), the method has no effect.

In all three cases, after the method returns, length() will return len.

An exception is thrown if len < 0 or this RandomAccessor is not writeable.

Specified by:

truncate in interface RandomAccessor

Parameters:

len - the desired content length

Throws:

IfsException - if the operation fails

length

public long length()
            throws IfsException

Gets the content length.

Specified by:

length in interface RandomAccessor

Returns:

the length, in bytes

Throws:

IfsException - if the operation fails

dispose

public void dispose()
             throws IfsException

Disposes this RandomAccessor, discarding any changes to the document.

To release resources held by the RandomAccessor, an application should call either close (to save changes) or dispose (to discard changes).

Specified by:

dispose in interface RandomAccessor

Throws:

IfsException - if the operation fails

close

public void close()
           throws IfsException

Closes this RandomAccessor, saving any changes to the document.

For a writeable RandomAccessor, a new ContentObject is created for the updated content, and the document's CONTENTOBJECT attribute is set to reference this new ContentObject. Any other changes specified by the DocumentDefinition supplied in creating this RandomAccessor are also applied.

For a non-writeable RandomAccessor, close is equivalent to dispose.

To release resources held by the RandomAccessor, an application should call either close (to save changes) or dispose (to discard changes).

Specified by:

close in interface RandomAccessor

Throws:

IfsException - if the operation fails

toString

public String toString()

Overrides:

toString in class Object

setContext

protected void setContext(S_LibrarySession session,
                          Transaction transaction)
                   throws IfsException

Called by DMRandomAccessor* methods to record the session and transaction context.

Parameters:

session - the session

transaction - the transaction in progress prior to the DMRandomAccessor* call, or null if none

Throws:

IfsException - if the operation fails

(Unpublished)