Java Java.io.CharArrayReader用法及代碼示例

// Java program illustrating the working of CharArrayReader class methods
// read(), skip(), ready()
// read(char[] char_array, int offset, int maxlen)
import java.io.*;
public class NewClass
{
    public static void main(String[] args) throws IOException
    {
        // Initializing the character array
        char[] geek = {'G', 'E', 'E', 'K', 'S'};
        // Initializing the char_array
        CharArrayReader char_array1 = new CharArrayReader(geek);
        CharArrayReader char_array2 = new CharArrayReader(geek);
        // Use of ready() method
        boolean check1 = char_array1.ready();
        if(check1 ==true)
            System.out.println("char_array1 is ready");
        else
            System.out.println("char_array1 is not ready");
        int a = 0;
        System.out.print("Use of read() method : ");
        // Use of read() method : reading each character one by one
        while((a = char_array1.read()) != -1)
        {
            char c1 = (char)a;
            System.out.println(c1);
            // Use of skip() method
            long char_no = char_array1.skip(1);
            System.out.println("Characters Skipped : "+(c1+1));
        }
        System.out.println("");
        // Use of ready() method
        boolean check2 = char_array2.ready();
        if(check2 ==true)
            System.out.println("char_array2 is ready");
        else
            System.out.println("char_array2 is not ready");
  // Use of read(char[] char_array, int offset, int maxlen) : reading a part of array
        char_array2.read(geek, 1, 2);
        int b = 0;
  System.out.print("Use of read(char[] char_array, int offset, int maxlen) method : ");
        while((b = char_array2.read()) != -1)
        {
            char c2 = (char)b;
            System.out.print(c2);
        }
    }
}

// Java program illustrating the working of FilterInputStream method
// mark(), reset()
// markSupported(), close()
import java.io.*;
public class NewClass
{
    public static void main(String[] args) throws Exception
    {
        // Initializing CharArrayReader
        CharArrayReader char_array = null;
        char[] geek = {'H', 'E', 'L', 'L', 'O', 'G',  'E',  'E',  'K', 'S'};
        try
        {
            char_array = new CharArrayReader(geek);
            // read() method : reading and printing Characters
            // one by one
            System.out.println("Char : "+(char)char_array.read());
            System.out.println("Char : "+(char)char_array.read());
            System.out.println("Char : "+(char)char_array.read());
            // mark() : read limiting the 'geek' input stream
            char_array.mark(0);
            System.out.println("mark() method comes to play");
            System.out.println("Char : "+(char)char_array.read());
            System.out.println("Char : "+(char)char_array.read());
            System.out.println("Char : "+(char)char_array.read());
            // Use of markSupported() :
            boolean check = char_array.markSupported();
            if (check == true )
                System.out.println("mark() supported\n");
            if (char_array.markSupported())
            {
                // reset() method : repositioning the stream to
                // marked positions.
                char_array.reset();
                System.out.println("reset() invoked");
                System.out.println("Char : "+(char)char_array.read());
                System.out.println("Char : "+(char)char_array.read());
            }
            else
                System.out.println("mark() method not supported.");
             
        }
        catch(Exception excpt)
        {
            // in case of I/O error
            excpt.printStackTrace();
        }
        finally
        {
            // Use of close() : releasing the resources back to the
            // GarbageCollector when closes
            if(char_array != null)
                char_array.close();
        }
    }
}