J2ME in a Nutshell

Name

Reader

Synopsis

Reader is an abstract class that defines the methods implemented by subclasses that provide character input. A Reader differs from an InputStream in that it works in terms of 16-bit Unicode characters rather than 8-bit bytes. An 8-bit InputStream can be converted to a sequence of Unicode characters by wrapping it with an instance of the InputStreamReader class, which is the only concrete subclass of Reader provided in the CLDC java.io package.

Most of the methods provided by Reader are the same as those available from InputStream, except that the fundamental unit of transfer is a char rather than a byte. The read() methods copy data from the data source into a character array, or return a single character held in the least significant 16 bits of an int. The skip() method skips over the given number of chars in the input source, or until end-of-file is reached. The mark(), reset() and markSupported() methods behave the same as an InputStream, except that the limit value passed to the mark() method is expressed in characters, not bytes.

Reader does not have an available() method that returns the amount of data waiting to be read without blocking. Instead, it has a ready() method that simply returns true if there is some data to be read, and false if there is not.

public abstract class Reader {  
// Protected Constructors
   protected Reader();  
   protected Reader( Object lock);    
// Public Instance Methods
   public abstract void close() throws IOException; public void  ...