?.?.?. ???????? ?.?. (email: [e-mail])

1
????????-??????????????? ?????? ?
????????????????
?????? 14 ????/????? (???????????)
?.?.?. ???????? ?.?. (email egrinkrug_at_hse.ru)
2
????????? Serializable

• ????????? java.io.Serializable
• ?? ????? ??????? (?????? ?????????)
• ?? ???????? ??????????? ??? ??????????? ???????
  (?? ????? ?????????? default-????????????
  ??????????????? ???????????? ??? ???? ?????????
  ??????? ??? ????????????/?????????????? ????? ??
  ?????????????? (!))
• ????????? ???????????????? ???????????? /
  ?????????????? ? ?????????????? ObjectOutputStrem
  / ObjectInputStream, ??????? ????? ????????????
  ????????????? ????? ??????????? ?????????
  ???????
• private void writeObject(java.io.ObjectOutputStrea
  m out) throws IOException
• private void readObject(java.io.ObjectInputStream
  in) throws IOException, ClassNotFoundException
• ? ???? ???? ??????? ????? ????????????,
  ??????????????, ????????
• out.defaultWriteObject()
• in.defaultReadObject() // ????? ???????
  ??????????? ????????? ?????? / ??????.

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????????? Externalizable

• ???? ????? ?? ?????????? ?? ???????? ????????????
  (Serizlizable), ?? ????? ?????????? ????
  ?????????? ???????? ?????? ? ?????? ????????
  ??????????? ????????? java.io.Externalazable
• ??? ?????????? ????????? ? ????????
• public interface Externalazable extends
  Serializable
• public void writeExternal (ObjectOutput out)
  throws IOException
• public void readExternal (ObjectInput in)
  throws IOException, ClassNotFoundException
• // ? ???????? ????????? ... ??????
  (????????? ?? ??????????, ? ??????...)
• ???????? ???????????? / ?????????????? ? ????
  ?????? ?????? ????? ? ????? ?????????? ? ??????
  ??????? (??? ????????????) ? ??????? ?????
  ????????? ??????? ??? ?????????? (???
  ???????...?)
• ????????? ?????? ??????? ???? ????????? ????
  ??????
• ? ??????? ?? ???????????? ??? ??????
  ???????????? (public)
• ??? ?????????? ??? ????????? ??????? ??????????
• ObjectOutput.writeObject(Object )
• ObjectInput.readObject()

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• ?????????
• ??????????? ???????????? ???????? ????????
  ????????
• ????????????? Externalizable ????? ????????
  ???????? ?????? / ?????????????? ????????
• ????????????? ?????? Externalizable-??????????
  ????????? ???????? ????????? ?????????????
  ??????? (??????? readExternal()) (????? ????
  ?????? ? ??????? ???????? ?????????... ???
  writeExternal())

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?????????? ??????? (????? File)

• ????????? ?????? ??????? ??? ?????? ? ??????????
  ??????
• ????? File ??? ?????? ? ?????? ???????.
• Java ?????? ?????????????? ???????? ???????????
  ?????? ??????????? ??? ?????????? ????????????,
  ????????? ? ??????? ????????????? ?????????
  ?????????? ?? ??????????? ??????????????
  ???????? native-???????
• ?????????? ??????????? File(String s) ????????
  ??? ?????
• ???? ??? ?? ??????, ?? ????? ???? ?? ????????
  ????????
• ??????? ??????? ??? ???? ???, ?? ????????
  ???????? Java VM (???? JVM ??????????? ??
  ????????? ??????).
• ???? ????? ? ????? ?????? ?? ??????????, ?? ??
  ?????????
• ??????????? ???????? ????? ?? ??????? ?????? File
  ???????? ?????-?? ??????? ??? ??????????? ???????
  ?????? File createNewFile(), ??????? ???????
  ????? ????, ???? ??? ?? ???? (?????? ??
  ??????...).

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• ???? ?????? File, ????? ??????, ?????????? ??
  ????? ????
• ??????? exists() -gt true/false
• ???? ???????????? ?????? File ? ?????????
  ???????? (null ???????? ??????? ???????) ?
  ????? ????? ? ???. ??????? ????? ???????
• ?????? (???????)
• ???????? ?????? File (?????? File ??????????
  ??????? ????? ? ????????)
• ??????, ??? ?????? ???????? ?????? File ?????
  ????????
• isDirectory()
• isFile()
• ??????? ?????? File, ?????????????? ???????
  (??????????) ????? ???
• File tempDir new File( File.separator
  temp)
• ????? ???? tempDir.mkdir() ??????? ??????????
  (???? ?? ??? ???...)

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• ?? ??????? ???????????? ?????????? ????????????
  ????, ???????? ? ?????? ???????? ??????? ????
  ???????????? ??????????? ?? ?????? File
  File.separator
• ? Win32FileSystem ??? backslash (\)
• ? Unix ??? forward slash (/).
• ???? ????? ? ????, ??? ? Java \ - ??? escape -
  ?????? (??? ????)

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????? ????-????? (????? java.nio)

• ????? java.nio ???????? ? JDK 1.4 (?? ?? ??? ???
  ?????????? new i/o)
• ??????????? ?????? ? ?????? (memory-mapped files)
  ???????? ??????????? ??????????? ????????????
  ?????? ? ?????? (??? ??????? ??????? ??????????)
  ???????? ?????? ?? ????????? ? ?????????????
  ????????? ??????????
• ????? java.nio ????? ??? ????? ????????
• ????????? ?????? ??? ??????
• ?????? FileInputStream, FileOutputStream ?
  RundomAccessFile ????? ????? getChannel(),
  ??????? ?????????? FileChannel
• ????????? ByteBuffer? ?? ??????
• ????? FileChannel ????? ????? map(), ??????? ????
  MappedByteBuffer
• MappedByteBuffer extends ByteBuffer.
• ??? ????????? ?????? ? ?????? ??????????? ?????
  ??????????? (MapMode) ? ??????? ?????,
  ???????????? ? ?????? (?????? ? ??????)

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• Java ???????????? ??? ?????? ???????????
• FileChannel.MapMode.READ_ONLY
• ????????? ????? ?????? ??? ?????? (????? -
  exception)
• FileChannel.MapMode.READ_WRITE
• ????? ????????? ??????, ?????-?????? ?????????
  ???????? ? ?????...
• FileChannel.MapMode.PRIVATE
• ? ????? ????? ??????, ?? ????????? ? ???? ??
  ????????.
• ???? ByteBuffer, ????? ???????????? ??? ????????
  ??? ?????? ?/??? ?????? ??????
• ?????? ???????????? ???????????????? ?/???
  ???????????? ?????? ? ??????.
• ? ?????? ?????????? ???????, ??????? ?????????? ?
  ?????????? ?????????? ??????? get() ? put()
• ???????? ???????????? ??????
• ????????, byte d buffer.get(i)
• ???????? ?????? / pfgbcm ??????? ??????,
  ????????
• get(byte bytes) ??? get(byte bytes, int
  offset, int length)

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• ????? ?????? / ?????? ???????? ?????????????
  ??????? ?????
• getInt(), getLong(), getShort(), getChar(),
  getFloat(), getDouble()
• putInt(), putLong(), putShort(), putChar(),
  putFloat(), putDouble()
• ??? ???? ????????????? ???????? ? ???????
  ???????? ?????? ? ????? (ByteOrder.LITTLE_ENDIAN
  ??? ByteOrder. BIG_ENDIAN)
• ??????, ????? ??????? ? ??????
• ByteOrder bo buffer.order()
• ?????????? ?????? ???????
• Buffer.order(ByteOrder.LITTLE_ENDIAN) // ???
  BIG_ENDIAN

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????????? ??????

• ??? ??????????? ????? ? ?????? ????????? ?????,
  ??????? ?????? ?? ???? ???? ??? ??? ?????? ?????
• ????? ??? ?????? ???????? ????????????? ????
  ?? ???????????? ?????? Buffer ???????????
  ByteBuffer, CharBuffer, FloatBuffer, IntBuffer, ?
  ?.?.
• ????? ????? ????????? ??????????????
• ????? (capacity), ??????? ?? ????????
• ??????? (position) ??????/?????? ??????????
  ????????
• ??????? (limit), ?? ??????? ??????/?????? ??
  ????? ??????
• ?????? (??????????????) ??? ??????????
  ??????/??????.

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• ????? ? ???????? ??????????? ??? ??????/??????
  ?????????? ? ?????
• ? ?????? ?????? ??????? ??????? ????? 0, ???????
  ????? ??????
• ????? get() ????? ???????? ?? ??? ???, ????
• Remaining (??????? - ???????) gt 0
• ????? flip () ????????????? ??????? ??????
  ??????? ???????, ? ??????? ?????? 0
• ????? clear() ?????? ??????? ? 0 ? ???????
  ?????? ??????
• ????????? ????????? ????? ???????????? ? ???????
  ??????? rewind(), mark(), reset().

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?????????? ??????

• ??? ? ?????? ? ???????????? ????? ? ??????,
  ?????????? ????? ???????? ????????? ??
  ???????????? ???????
• ?????????? ????? ?????? ?????, ???? ?????????
  ???????? ????????? ???????? ? ????? ??????.
• ???? ??????????? ???????? ??????? ??????
  FileChannel
• FileLock lock channel.lock() // ????????
  ??????????? ??????????...
• FileLock lock channel.tryLock() // ??????????
  ??? null, ???? ????? ???...
• ????? ????????????? ????? ?????
• FileLock lock(long start, long size, boolean
  exclusive)
• FileLock tryLock(long start, long size, boolean
  exclusive)
• excusive true, ???? ??????????????
  ?????????? (??? ??????)
• exclusive false, ???? ?????????? ??????????
  (??? ????????????? ??????) ??? ????????
  ?????????????? ?? ????? ?????????????
  ?????????...

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(No Transcript)
15
?????????-??????????????? ??? (native code)

• ?????? ?????????? ???????????? ?????????-?????????
  ?????? ???
• ??? ???? ??????? ??????????? ??????, ???????
  ??????? ???????????? (OpenGL, ????????)
• ????????? ??????? ?????????? OS ??? ??????
• ??????? ??????????? ??? ????????? ??????? (??
  ????? ???? just-in-time ?????????? ??????????
  ??????? ? ????????????????? ?-?????).
• ??? ????????????? native-???? ???? ????????
  ???????? ?? ??????
• ??? ???????, ???????????? ?? ?????? ????? ???? ?
  native-?????, ? ??? ???? ????????? ?????? ?
  ??????? ???????. ???? ???????????? ???????
  ??????? ??????? ??????? ????????? ?????,
  ???????? ????????? ?? ? java...

16
????? C-??????? ?? java-?????????

• ? ????????? ?????? java ???????????
  native-???????, ????????,
• public native String translateEnglishIntoRussian
  (String s)
• ?????, ?????????? ??? ?????????? native-??????,
  ??????????????, ?? ??? ??????????
  UnsatisfiedLinkError - JVM ?? ????? ????? ??????
  ???????. Native-????? ????? ???? ??? ?? ????
  ???????????.
• ?????? ????
• ??????? ?? ????? C ???????? (??????????),
  ??????? ??????????? ????? ?? java ? ????????? ?
  ?????? C-?????? ? ?????????, ???? ?????
  ????????? ?? ????? JVM ? ???????? ??
  ????????????????? C-???????
• ??????? ??????????? ??????????? ?????????? (dll
  ? Windows), ??????? ???????????? ??? ????????
• ???????????? ??????????? ????? java
  System.loadLibrary(), ?????? ??? ???? dll

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• ?????????? ???? ?????????? ??????
• ?????? ????????????? java-????? ?
  native-????????
• ????? ?????????? ??????????? ??????? ?? ????????
  jdk/bin ??? ????????? javah.exe ??????????
  ??????? ?????? ?????-????. ??? ??????? ??????????
  Header-???? (lt???_??????gt.h) ??? ???????? ????
  ??? ????????????? ?-????????????. ? ??? ?????
  ???????????? jni.h, ??? ?????????? ???
  ??????????? ?????...
• ? ??????????????? ???????????? ????? ?????
  ???????? ?????????? ???????, ??????? ????
  ??????????? ?? ?.
• ??? ????? ????????????? ?-??????? ?????????? ?
  dll, ????????,
• myNatives.dll
• ? java-??????, ??? ????? native-??????, ??????
  ??????????? ????????????? (????? ?? ?????
  ?????????)
• static System.loadLibrary(myNatives)
• ???? myNatives.dll ???? ???????? ? ?????? ?????
  ...

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• ??????? ??????, ????????? ?
• ????????? ??????? ????????????, ??????????? ?
  ????????????? ???????
• ????????? ?????????? ? ???????????? ????????
• ??????? ? ????????????? ?????????
• ????????? ?????? ? ?????????????? ????????
• ? ?.?.
• ??? ???, ??? ??????? C (C) ??? ?????? ??
  ????????.

19
Q A

• Have a nice test !