org.eclipse.birt.core.archive
Class RAFileInputStream

java.lang.Object
  extended by java.io.InputStream
      extended by org.eclipse.birt.core.archive.RAInputStream
          extended by org.eclipse.birt.core.archive.RAFileInputStream
All Implemented Interfaces:
java.io.Closeable

public class RAFileInputStream
extends RAInputStream


Constructor Summary
RAFileInputStream(java.io.RandomAccessFile parentFile, long startPos, long endPos)
           
 
Method Summary
 int available()
          Returns the number of bytes that can be read (or skipped over) from this random access input stream without blocking by the next caller of a method for this input stream.
 long getOffset()
           
 long getStreamLength()
           
 long length()
           
 int read()
          The same behavior as InputStream.read().
Reads the next byte of data from the input stream.
 int read(byte[] b, int off, int len)
          The same behavior as InputStream.read(byte b[], int off, int len ).
Reads up to len bytes of data from the input stream into an array of bytes.
 void readFully(byte[] b, int off, int len)
          The same behavior as RandomAccessFile.readFully(byte b[], int off, int len) Reads exactly len bytes from this file into the byte array, starting at the current file pointer.
 int readInt()
          The same behavior as RandomAccessFile.readInt().
 long readLong()
          Reads a signed 64-bit integer from this file.
 void refresh()
           
 void seek(long localPos)
          Move the file pointer to the new location in the stream
 
Methods inherited from class java.io.InputStream
close, mark, markSupported, read, reset, skip
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

RAFileInputStream

public RAFileInputStream(java.io.RandomAccessFile parentFile,
                         long startPos,
                         long endPos)
Parameters:
parentFile - - underlying RandomAccess file
startPos - - the (global) position of the first character in parentFile
endPos - - the (global) position of EOF mark (not a valid character in the file)
Method Detail

refresh

public void refresh()
             throws java.io.IOException
Specified by:
refresh in class RAInputStream
Throws:
java.io.IOException

read

public int read()
         throws java.io.IOException
The same behavior as InputStream.read().
Reads the next byte of data from the input stream. The value byte is returned as an int in the range 0 to 255. If no byte is available because the end of the stream has been reached, the value -1 is returned. This method blocks until input data is available, the end of the stream is detected, or an exception is thrown.

A subclass must provide an implementation of this method.

Specified by:
read in class java.io.InputStream
Returns:
the next byte of data, or -1 if the end of the stream is reached.
Throws:
java.io.IOException - if an I/O error occurs.

read

public int read(byte[] b,
                int off,
                int len)
         throws java.io.IOException
The same behavior as InputStream.read(byte b[], int off, int len ).
Reads up to len bytes of data from the input stream into an array of bytes. If no byte is available because the end of the stream has been reached, the value -1 is returned. This method blocks until input data is available, the end of the stream is detected, or an exception is thrown.

A subclass must provide an implementation of this method.

Overrides:
read in class java.io.InputStream
Returns:
the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached
Throws:
java.io.IOException - if an I/O error occurs.

readInt

public int readInt()
            throws java.io.IOException
The same behavior as RandomAccessFile.readInt().
Reads a signed 32-bit integer from this file. This method reads 4 bytes from the file, starting at the current file pointer. If the bytes read, in order, are b1, b2, b3, and b4, where 0 <= b1, b2, b3, b4 <= 255, then the result is equal to:
     (b1 << 24) | (b2 << 16) + (b3 << 8) + b4
 

This method blocks until the four bytes are read, the end of the stream is detected, or an exception is thrown.

Specified by:
readInt in class RAInputStream
Returns:
the next four bytes of this stream, interpreted as an int.
Throws:
java.io.EOFException - if this stream reaches the end before reading four bytes.
java.io.IOException - if an I/O error occurs.

readLong

public final long readLong()
                    throws java.io.IOException
Reads a signed 64-bit integer from this file. This method reads eight bytes from the file, starting at the current file pointer. If the bytes read, in order, are b1, b2, b3, b4, b5, b6, b7, and b8, where:
     0 <= b1, b2, b3, b4, b5, b6, b7, b8 <=255,
 

then the result is equal to:

     ((long)b1 << 56) + ((long)b2 << 48)
     + ((long)b3 << 40) + ((long)b4 << 32)
     + ((long)b5 << 24) + ((long)b6 << 16)
     + ((long)b7 << 8) + b8
 

This method blocks until the eight bytes are read, the end of the stream is detected, or an exception is thrown.

Specified by:
readLong in class RAInputStream
Returns:
the next eight bytes of this file, interpreted as a long.
Throws:
java.io.EOFException - if this file reaches the end before reading eight bytes.
java.io.IOException - if an I/O error occurs.

readFully

public final void readFully(byte[] b,
                            int off,
                            int len)
                     throws java.io.IOException
The same behavior as RandomAccessFile.readFully(byte b[], int off, int len) Reads exactly len bytes from this file into the byte array, starting at the current file pointer. This method reads repeatedly from the file until the requested number of bytes are read. This method blocks until the requested number of bytes are read, the end of the stream is detected, or an exception is thrown.

Specified by:
readFully in class RAInputStream
Parameters:
b - the buffer into which the data is read.
off - the start offset of the data.
len - the number of bytes to read.
Throws:
java.io.EOFException - if this file reaches the end before reading all the bytes.
java.io.IOException - if an I/O error occurs.

getStreamLength

public long getStreamLength()
Returns:
the length of the stream

seek

public void seek(long localPos)
          throws java.io.IOException
Move the file pointer to the new location in the stream

Specified by:
seek in class RAInputStream
Parameters:
localPos - - the new local postion in the stream. The localPos starts from 0.
Throws:
java.io.IOException

getOffset

public long getOffset()
               throws java.io.IOException
Specified by:
getOffset in class RAInputStream
Throws:
java.io.IOException

length

public long length()
            throws java.io.IOException
Specified by:
length in class RAInputStream
Throws:
java.io.IOException

available

public int available()
              throws java.io.IOException
Description copied from class: RAInputStream
Returns the number of bytes that can be read (or skipped over) from this random access input stream without blocking by the next caller of a method for this input stream. The next caller might be the same thread or another thread.

This abstract class is extended by RAFolderInputStream and RAFileInputStream

The available method returns -1 when no more data because the end of the stream has been reached.

and returns Integer.MAX_VALUE when bytes of data is larger then Integer.MAX_VALUE.

Specified by:
available in class RAInputStream
Throws:
java.io.IOException


Copyright © 2008 Actuate Corp. All rights reserved.