# CpioArchiveOutputStream (Apache Commons Compress 1.13 API)

org.apache.commons.compress.archivers.cpio

## Class CpioArchiveOutputStream

- java.lang.Object
- - java.io.OutputStream
  - - org.apache.commons.compress.archivers.ArchiveOutputStream
    - - org.apache.commons.compress.archivers.cpio.CpioArchiveOutputStream

- All Implemented Interfaces:
    Closeable, Flushable, AutoCloseable, CpioConstants

      public class CpioArchiveOutputStream
      extends ArchiveOutputStream
      implements CpioConstants

  CPIOArchiveOutputStream is a stream for writing CPIO streams. All formats of CPIO are supported (old ASCII, old binary, new portable format and the new portable format with CRC).

  An entry can be written by creating an instance of CpioArchiveEntry and fill it with the necessary values and put it into the CPIO stream. Afterwards write the contents of the file into the CPIO stream. Either close the stream by calling finish() or put a next entry into the cpio stream.

       CpioArchiveOutputStream out = new CpioArchiveOutputStream(
               new FileOutputStream(new File("test.cpio")));
       CpioArchiveEntry entry = new CpioArchiveEntry();
       entry.setName("testfile");
       String contents = "12345";
       entry.setFileSize(contents.length());
       entry.setMode(CpioConstants.C_ISREG); // regular file
       ... set other attributes, e.g. time, number of links
       out.putArchiveEntry(entry);
       out.write(testContents.getBytes());
       out.close();

  Note: This implementation should be compatible to cpio 2.5

  This class uses mutable fields and is not considered threadsafe.

  based on code from the jRPM project (jrpm.sourceforge.net)

- - ### Field Summary

    - ### Fields inherited from interface org.apache.commons.compress.archivers.cpio.CpioConstants

      `BLOCK_SIZE, 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, CPIO_TRAILER, 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

    Constructors
    Constructor and Description
    `CpioArchiveOutputStream(OutputStream out)` Construct the cpio output stream.
    `CpioArchiveOutputStream(OutputStream out, short format)` Construct the cpio output stream with a specified format, a blocksize of `BLOCK_SIZE` and using ASCII as the file name encoding.
    `CpioArchiveOutputStream(OutputStream out, short format, int blockSize)` Construct the cpio output stream with a specified format using ASCII as the file name encoding.
    `CpioArchiveOutputStream(OutputStream out, short format, int blockSize, String encoding)` Construct the cpio output stream with a specified format using ASCII as the file name encoding.
    `CpioArchiveOutputStream(OutputStream out, String encoding)` Construct the cpio output stream.

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `close()` Closes the CPIO output stream as well as the stream being filtered.
    `void` | `closeArchiveEntry()` Closes the archive entry, writing any trailer information that may be required.
    `ArchiveEntry` | `createArchiveEntry(File inputFile, String entryName)` Creates a new ArchiveEntry.
    `void` | `finish()` Finishes writing the contents of the CPIO output stream without closing the underlying stream.
    `void` | `putArchiveEntry(ArchiveEntry entry)` Begins writing a new CPIO file entry and positions the stream to the start of the entry data.
    `void` | `write(byte[] b, int off, int len)` Writes an array of bytes to the current CPIO entry data.

    - ### Methods inherited from class org.apache.commons.compress.archivers.ArchiveOutputStream

      `canWriteEntryData, count, count, getBytesWritten, getCount, write`

    - ### Methods inherited from class java.io.OutputStream

      `flush, write`

    - ### Methods inherited from class java.lang.Object

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

- - ### Constructor Detail

    - #### CpioArchiveOutputStream

          public CpioArchiveOutputStream(OutputStream out,
                                 short format)

      Construct the cpio output stream with a specified format, a blocksize of `BLOCK_SIZE` and using ASCII as the file name encoding.
      Parameters:
        `out` - The cpio stream
        `format` - The format of the stream

    - #### CpioArchiveOutputStream

          public CpioArchiveOutputStream(OutputStream out,
                                 short format,
                                 int blockSize)

      Construct the cpio output stream with a specified format using ASCII as the file name encoding.
      Parameters:
        `out` - The cpio stream
        `format` - The format of the stream
        `blockSize` - The block size of the archive.
      Since:
        1.1

    - #### CpioArchiveOutputStream

          public CpioArchiveOutputStream(OutputStream out,
                                 short format,
                                 int blockSize,
                                 String encoding)

      Construct the cpio output stream with a specified format using ASCII as the file name encoding.
      Parameters:
        `out` - The cpio stream
        `format` - The format of the stream
        `blockSize` - The block size of the archive.
        `encoding` - The encoding of file names to write - use null for the platform's default.
      Since:
        1.6

    - #### CpioArchiveOutputStream

          public CpioArchiveOutputStream(OutputStream out)

      Construct the cpio output stream. The format for this CPIO stream is the "new" format using ASCII encoding for file names
      Parameters:
        `out` - The cpio stream

    - #### CpioArchiveOutputStream

          public CpioArchiveOutputStream(OutputStream out,
                                 String encoding)

      Construct the cpio output stream. The format for this CPIO stream is the "new" format.
      Parameters:
        `out` - The cpio stream
        `encoding` - The encoding of file names to write - use null for the platform's default.
      Since:
        1.6

  - ### Method Detail

    - #### putArchiveEntry

          public void putArchiveEntry(ArchiveEntry entry)
                               throws IOException

      Begins writing a new CPIO file entry and positions the stream to the start of the entry data. Closes the current entry if still active. The current time will be used if the entry has no set modification time and the default header format will be used if no other format is specified in the entry.
      Specified by:
        `putArchiveEntry` in class `ArchiveOutputStream`
      Parameters:
        `entry` - the CPIO cpioEntry to be written
      Throws:
        `IOException` - if an I/O error has occurred or if a CPIO file error has occurred
        `ClassCastException` - if entry is not an instance of CpioArchiveEntry

    - #### closeArchiveEntry

          public void closeArchiveEntry()
                                 throws IOException

      Description copied from class: `ArchiveOutputStream`
      Closes the archive entry, writing any trailer information that may be required.
      Specified by:
        `closeArchiveEntry` in class `ArchiveOutputStream`
      Throws:
        `IOException` - if an I/O error occurs

    - #### write

          public void write(byte[] b,
                   int off,
                   int len)
                     throws IOException

      Writes an array of bytes to the current CPIO entry data. This method will block until all the bytes are written.
      Overrides:
        `write` in class `OutputStream`
      Parameters:
        `b` - the data to be written
        `off` - the start offset in the data
        `len` - the number of bytes that are written
      Throws:
        `IOException` - if an I/O error has occurred or if a CPIO file error has occurred

    - #### finish

          public void finish()
                      throws IOException

      Finishes writing the contents of the CPIO output stream without closing the underlying stream. Use this method when applying multiple filters in succession to the same output stream.
      Specified by:
        `finish` in class `ArchiveOutputStream`
      Throws:
        `IOException` - if an I/O exception has occurred or if a CPIO file error has occurred

    - #### close

          public void close()
                     throws IOException

      Closes the CPIO output stream as well as the stream being filtered.
      Specified by:
        `close` in interface `Closeable`
      Specified by:
        `close` in interface `AutoCloseable`
      Overrides:
        `close` in class `OutputStream`
      Throws:
        `IOException` - if an I/O error has occurred or if a CPIO file error has occurred

    - #### createArchiveEntry

          public ArchiveEntry createArchiveEntry(File inputFile,
                                        String entryName)
                                          throws IOException

      Creates a new ArchiveEntry. The entryName must be an ASCII encoded string.
      Specified by:
        `createArchiveEntry` in class `ArchiveOutputStream`
      Parameters:
        `inputFile` - the file to create the entry from
        `entryName` - name to use for the entry
      Returns:
        the ArchiveEntry set up with details from the file
      Throws:
        `IOException` - if an I/O error occurs
      See Also:
        `ArchiveOutputStream.createArchiveEntry(java.io.File, java.lang.String)`

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