apache-comnons系列之commons-io-2.5 org.apache.commons.io.IOUtils學習筆記

概述

• OutputStream、InputStream、Writer、Reader學習筆記
  • http://blog.csdn.net/undergrowth/article/details/43820639
• General IO stream manipulation utilities.
  • This class provides static utility methods for input/output operations.
    • closeQuietly - these methods close a stream ignoring nulls and exceptions
    • toXxx/read - these methods read data from a stream
    • write - these methods write data to a stream
    • copy - these methods copy all the data from one stream to another
    • contentEquals - these methods compare the content of two streams
  • byte-to-char methods and char-to-byte methods
    • default encoding and encoding
  • buffered internally
    • default buffer size of 4K

測試

• org.apache.commons.io.IOUtilsTestCase
• closeQuietly
  • Closes an

    OutputStream

    unconditionally
  • Equivalent to {@link OutputStream#close()}, except any exceptions will be ignored
  • This is typically used in finally blocks
  • 借助于closeable.close()關閉源
• toByteArray
  • 依賴copy
• copy
  • 依賴copyLarge,copyLarge以4k為一組複制資料
  • Large streams (over 2GB) will return a bytes copied value of

    -1

    after the copy has completed since the correct number of bytes cannot be returned as an int
• readLines
  • This method buffers the input internally, so there is no need to use a

    BufferedInputStream

    .
• contentEquals
  • Compares the contents of two Streams to determine if they are equal or not.
  • This method buffers the input internally using

    BufferedInputStream

    if they are not already buffered.
  • 一個byte一個byte比較/位元組和字元