英文不好，拿來做閱讀練習。。。。一步一步，有些地方可能表達有問題，見諒。

Overview of I/O Streams

i/o流的概述

To bring in information, a program opens a stream on an information source (a file, memory, a socket) and reads the information sequentially, as shown here:

為了獲取資訊，程式在資訊源（檔案，記憶體，socket）之間建立了一個流，然後按順序讀取資訊，如下圖所示：

！sequentially 這裡怎麼翻譯不是很明白。

Similarly, a program can send information to an external destination by opening a stream to a destination and writing the information out sequentially, like this:

相似的過程，程式通過和外部的資訊送達目標建立起一個流，然後把資訊傳送到目標，按順序寫出,像如下圖一樣：

No matter where the data is coming from or going to and no matter what its type, the algorithms for sequentially reading and writing data are basically the same:

無論資料從哪裡來或者到哪裡，也不管資料在那種介質中，按序讀寫資料的演算法基本是相同的：

Java.io包中包含了一系列流的類，這些類支援讀寫操作的演算法。為了使用這些類，程式中需要引入java.io包。這些流的類有2個分支，分支是基於他們操作時候的資料型別（是字元還是位元組）。

Character Streams

字元流

Reader provides the API and partial implementation for readers--streams that read 16-bit characters--and Writer provides the API and partial implementation for writers--streams that write 16-bit characters. Subclasses of Reader and Writer implement specialized streams and are divided into two categories: those that read from or write to data sinks (shown in gray in the following figures) and those that perform some sort of processing (shown in white). The figure shows the class hierarchies for the Reader and Writer classes.

Reader 和 Writer 是java.io包中那些字元流的抽象父類。Reader為讀字元流提供了API和部分的實現--這些流讀取16為的字元，Wirter為寫字元流提供了API和部分的實現—這些流寫入16為的字元。Reader和Writer的子類實現了專門的流，他們被分為2類：那些從節點讀或者寫入管道的類（在下圖中顯示為灰色）和那些執行了排序過程的類（顯示為白色）。下面的圖顯示了Reader和Writer類們的層級關係。

Most programs should use readers and writers to read and write textual information. The reason is that they can handle any character in the Unicode character set, whereas the byte streams are limited to ISO-Latin-1 8-bit bytes.

很多程式應該使用字元讀寫類來讀或寫文字資訊。因為他們可以處理任何Unicode編碼的字元，而位元組流卻限制在處理ISO-Latin-1 8-bit位元組上。

Byte Streams

位元組流

為了能夠讀寫8位的位元組，程式應當使用位元組流，也就是InputStream和OutputStream的子類。InputStream和OutputStream為輸入流（讀8位位元組的流）和輸出流（寫8位位元組的流）提供了API和部分實現。這些流典型的用法是讀寫如圖片和聲音的二進位制資料。有2中位元組流，ObjectInputStream 和 ObjectOutputStream,被用在物件的序列化中。這些類被Serializetion類覆蓋。

As with Reader and Writer, subclasses of InputStream and OutputStream provide specialized I/O that falls into two categories, as shown in the following class hierarchy figure: data sink streams (shaded) and processing streams (unshaded).

和Reader和Writer相比，InputStream和OutputStream用於處理專門I/O的子類也分為2類，如下圖顯示了他們的類層級：節點流（陰影的）和處理流（沒有陰影的）

Understanding the I/O Superclasses

理解I/O的父類

Reader and InputStream define similar APIs but for different data types. For example, Reader contains these methods for reading characters and arrays of characters:

Reader 和 InputStream 定義了相似的API但是不同的資料型別。例如，Reader包含了這些方法用於讀取字元和字元陣列：

int read()

int read(char cbuf[])

int read(char cbuf[], int offset, int length)

InputStream defines the same methods but for reading bytes and arrays of bytes:

InputStream 定義了相同的方法但是用於讀取位元組和位元組陣列。

int read()

int read(byte cbuf[])

int read(byte cbuf[], int offset, int length)

Also, both Reader and InputStream provide methods for marking a location in the stream, skipping input, and resetting the current position.

相同的，Reader 和 InputStream都提供了方法用於標記流中的座標，跳過輸入，和重置當前座標。

Writer and OutputStream are similarly parallel. Writer defines these methods for writing characters and arrays of characters:

Writer 和 OutputStream 也非常相似。Writer定義了這些方法用於寫出字元和字元陣列。

int write(int c)

int write(char cbuf[])

int write(char cbuf[], int offset, int length)

And OutputStream defines the same methods but for bytes:

OutputStream定義了這些相同的方法但是用於位元組。

int write(int c)

int write(byte cbuf[])

int write(byte cbuf[], int offset, int length)

All of the streams--readers, writers, input streams, and output streams--are automatically opened when created. You can close any stream explicitly by calling its close method. Or the garbage collector can implicitly close it, which occurs when the object is no longer referenced.

所有的流-- readers, writers, input streams, and output streams—建立的時候會自動開啟。你能通過close方法明確的關閉任何一個流。或者是垃圾回收期在暗中關閉，這種情況是發生在物件不再被引用的時候。