com.jguild.jrpm.io.cpio
Class CPIOInputStream

java.lang.Object
  java.io.InputStream
      java.io.FilterInputStream
          com.jguild.jrpm.io.cpio.CPIOInputStream

All Implemented Interfaces:

CPIOConstants

public class CPIOInputStream

extends java.io.FilterInputStream

implements CPIOConstants

CPIOInputStream is a stream for reading cpio streams. All formats of cpio are supported (old ascii, old binary, new portable format and the new portable format with crc).

The stream can be read by extracting a cpio entry (containing all informations about a entry) and afterwards reading from the stream the file specified by the entry.

 CPIOInputStream cpioIn = new CPIOInputStream(new BufferedInputStream(new FileInputStream(new File("test.cpio"))));
 CPIOEntry cpioEntry;

 while ((cpioEntry = cpioIn.getNextEntry()) != null) {
     System.out.println(cpioEntry.getName());
     int tmp;
     StringBuffer buf = new StringBuffer();
     while ((tmp = cpIn.read()) != -1) {
        buf.append((char) tmp);
     }
     System.out.println(buf.toString());
 }
 cpioIn.close();
 

Note: This implementation should be compatible to cpio 2.5

Author:

Michael Kuss

Field Summary

Fields inherited from class java.io.FilterInputStream

in

Fields inherited from interface com.jguild.jrpm.io.cpio.CPIOConstants

C_IRGRP, C_IROTH, C_IRUSR, C_ISBLK, C_ISCHR, C_ISDIR, C_ISFIFO, C_ISGID, C_ISLNK, C_ISNWK, C_ISREG, C_ISSOCK, C_ISUID, C_ISVTX, C_IWGRP, C_IWOTH, C_IWUSR, C_IXGRP, C_IXOTH, C_IXUSR, FORMAT_NEW, FORMAT_NEW_CRC, FORMAT_NEW_MASK, FORMAT_OLD_ASCII, FORMAT_OLD_BINARY, FORMAT_OLD_MASK, MAGIC_NEW, MAGIC_NEW_CRC, MAGIC_OLD_ASCII, MAGIC_OLD_BINARY, S_IFMT

Constructor Summary

CPIOInputStream(java.io.InputStream in)
Construct the cpio input stream

Method Summary

int	available() Returns 0 after EOF has reached for the current entry data, otherwise always return 1.
void	close() Closes the CPIO input stream.
void	closeEntry() Closes the current CPIO entry and positions the stream for reading the next entry.
CPIOEntry	getNextEntry() Reads the next CPIO file entry and positions stream at the beginning of the entry data.
int	read() Reads a byte of data.
int	read(byte[] b, int off, int len) Reads from the current CPIO entry into an array of bytes.
long	skip(long n) Skips specified number of bytes in the current CPIO entry.

Methods inherited from class java.io.FilterInputStream

mark, markSupported, read, reset

Methods inherited from class java.lang.Object

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

Constructor Detail

CPIOInputStream

public CPIOInputStream(java.io.InputStream in)

Construct the cpio input stream

Parameters:

in - The cpio stream

Method Detail

available

public int available()
              throws java.io.IOException

Returns 0 after EOF has reached for the current entry data, otherwise always return 1.

Programs should not count on this method to return the actual number of bytes that could be read without blocking.

Returns:

1 before EOF and 0 after EOF has reached for current entry.

Throws:

java.io.IOException - if an I/O error has occurred or if a CPIO file error has occurred

close

public void close()
           throws java.io.IOException

Closes the CPIO input stream.

Throws:

java.io.IOException - if an I/O error has occurred

closeEntry

public void closeEntry()
                throws java.io.IOException

Closes the current CPIO entry and positions the stream for reading the next entry.

Throws:

java.io.IOException - if an I/O error has occurred or if a CPIO file error has occurred

getNextEntry

public CPIOEntry getNextEntry()
                       throws java.io.IOException

Reads the next CPIO file entry and positions stream at the beginning of the entry data.

Returns:

the CPIOEntry just read

Throws:

java.io.IOException - if an I/O error has occurred or if a CPIO file error has occurred

read

public int read()
         throws java.io.IOException

Reads a byte of data. This method will block until enough input is available.

Returns:

the byte read, or -1 if end of input is reached

Throws:

java.io.IOException - if an I/O error has occurred or if a CPIO file error has occurred

read

public int read(byte[] b,
                int off,
                int len)
         throws java.io.IOException

Reads from the current CPIO entry into an array of bytes. Blocks until some input is available.

Parameters:

b - the buffer into which the data is read

off - the start offset of the data

len - the maximum number of bytes read

Returns:

the actual number of bytes read, or -1 if the end of the entry is reached

Throws:

java.io.IOException - if an I/O error has occurred or if a CPIO file error has occurred

skip

public long skip(long n)
          throws java.io.IOException

Skips specified number of bytes in the current CPIO entry.

Parameters:

n - the number of bytes to skip

Returns:

the actual number of bytes skipped

Throws:

java.io.IOException - if an I/O error has occurred

java.lang.IllegalArgumentException - if n < 0