org.apache.poi.poifs.filesystem
Class DocumentInputStream

java.lang.Object
  extended by java.io.InputStream
      extended by org.apache.poi.poifs.filesystem.DocumentInputStream
All Implemented Interfaces:
java.io.Closeable, LittleEndianInput
Direct Known Subclasses:
NDocumentInputStream, ODocumentInputStream

public class DocumentInputStream
extends java.io.InputStream
implements LittleEndianInput

This class provides methods to read a DocumentEntry managed by a POIFSFileSystem or NPOIFSFileSystem instance. It creates the appropriate one, and delegates, allowing us to work transparently with the two.


Field Summary
protected static int EOF
          returned by read operations if we're at end of document
protected static int SIZE_INT
           
protected static int SIZE_LONG
           
protected static int SIZE_SHORT
           
 
Constructor Summary
protected DocumentInputStream()
          For use by downstream implementations
  DocumentInputStream(DocumentEntry document)
          Create an InputStream from the specified DocumentEntry
  DocumentInputStream(NPOIFSDocument document)
          Create an InputStream from the specified Document
  DocumentInputStream(OPOIFSDocument document)
          Create an InputStream from the specified Document
 
Method Summary
 int available()
           
 void close()
           
 void mark(int ignoredReadlimit)
           
 boolean markSupported()
          Tests if this input stream supports the mark and reset methods.
 int read()
           
 int read(byte[] b)
           
 int read(byte[] b, int off, int len)
           
 byte readByte()
           
 double readDouble()
           
 void readFully(byte[] buf)
           
 void readFully(byte[] buf, int off, int len)
           
 int readInt()
           
 long readLong()
           
 void readPlain(byte[] buf, int off, int len)
          Usually acts the same as LittleEndianInput.readFully(byte[], int, int), but for an encrypted stream the raw (unencrypted) data is filled
 short readShort()
           
 int readUByte()
           
 long readUInt()
           
 int readUShort()
           
 void reset()
          Repositions this stream to the position at the time the mark() method was last called on this input stream.
 long skip(long n)
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

EOF

protected static final int EOF
returned by read operations if we're at end of document

See Also:
Constant Field Values

SIZE_SHORT

protected static final int SIZE_SHORT
See Also:
Constant Field Values

SIZE_INT

protected static final int SIZE_INT
See Also:
Constant Field Values

SIZE_LONG

protected static final int SIZE_LONG
See Also:
Constant Field Values
Constructor Detail

DocumentInputStream

protected DocumentInputStream()
For use by downstream implementations


DocumentInputStream

public DocumentInputStream(DocumentEntry document)
                    throws java.io.IOException
Create an InputStream from the specified DocumentEntry

Parameters:
document - the DocumentEntry to be read
Throws:
java.io.IOException - if the DocumentEntry cannot be opened (like, maybe it has been deleted?)

DocumentInputStream

public DocumentInputStream(OPOIFSDocument document)
Create an InputStream from the specified Document

Parameters:
document - the Document to be read

DocumentInputStream

public DocumentInputStream(NPOIFSDocument document)
Create an InputStream from the specified Document

Parameters:
document - the Document to be read
Method Detail

available

public int available()
Specified by:
available in interface LittleEndianInput
Overrides:
available in class java.io.InputStream

close

public void close()
Specified by:
close in interface java.io.Closeable
Overrides:
close in class java.io.InputStream

mark

public void mark(int ignoredReadlimit)
Overrides:
mark in class java.io.InputStream

markSupported

public boolean markSupported()
Tests if this input stream supports the mark and reset methods.

Overrides:
markSupported in class java.io.InputStream
Returns:
true always

read

public int read()
         throws java.io.IOException
Specified by:
read in class java.io.InputStream
Throws:
java.io.IOException

read

public int read(byte[] b)
         throws java.io.IOException
Overrides:
read in class java.io.InputStream
Throws:
java.io.IOException

read

public int read(byte[] b,
                int off,
                int len)
         throws java.io.IOException
Overrides:
read in class java.io.InputStream
Throws:
java.io.IOException

reset

public void reset()
Repositions this stream to the position at the time the mark() method was last called on this input stream. If mark() has not been called this method repositions the stream to its beginning.

Overrides:
reset in class java.io.InputStream

skip

public long skip(long n)
          throws java.io.IOException
Overrides:
skip in class java.io.InputStream
Throws:
java.io.IOException

readByte

public byte readByte()
Specified by:
readByte in interface LittleEndianInput

readDouble

public double readDouble()
Specified by:
readDouble in interface LittleEndianInput

readShort

public short readShort()
Specified by:
readShort in interface LittleEndianInput

readFully

public void readFully(byte[] buf)
Specified by:
readFully in interface LittleEndianInput

readFully

public void readFully(byte[] buf,
                      int off,
                      int len)
Specified by:
readFully in interface LittleEndianInput

readLong

public long readLong()
Specified by:
readLong in interface LittleEndianInput

readInt

public int readInt()
Specified by:
readInt in interface LittleEndianInput

readUShort

public int readUShort()
Specified by:
readUShort in interface LittleEndianInput

readUByte

public int readUByte()
Specified by:
readUByte in interface LittleEndianInput

readUInt

public long readUInt()

readPlain

public void readPlain(byte[] buf,
                      int off,
                      int len)
Description copied from interface: LittleEndianInput
Usually acts the same as LittleEndianInput.readFully(byte[], int, int), but for an encrypted stream the raw (unencrypted) data is filled

Specified by:
readPlain in interface LittleEndianInput
Parameters:
buf - the byte array to receive the bytes
off - the start offset into the byte array
len - the amount of bytes to fill