Java The Complete Reference, Seventh Edition

582 Part II: The Java Library

CharArrayReader

CharArrayReaderis an implementation of an input stream that uses a character array as the

source. This class has two constructors, each of which requires a character array to provide

the data source:

CharArrayReader(chararray[ ])

CharArrayReader(chararray[ ], intstart, intnumChars)

Here,arrayis the input source. The second constructor creates aReaderfrom a subset of

your character array that begins with the character at the index specified bystartand is

numCharslong.

The following example uses a pair ofCharArrayReaders:

// Demonstrate CharArrayReader.

import java.io.*;

public class CharArrayReaderDemo {

public static void main(String args[]) throws IOException {

String tmp = "abcdefghijklmnopqrstuvwxyz";

int length = tmp.length();

char c[] = new char[length];

tmp.getChars(0, length, c, 0);

CharArrayReader input1 = new CharArrayReader(c);

CharArrayReader input2 = new CharArrayReader(c, 0, 5);

int i;

System.out.println("input1 is:");

while((i = input1.read()) != -1) {

System.out.print((char)i);

}

System.out.println();

System.out.println("input2 is:");

while((i = input2.read()) != -1) {

System.out.print((char)i);

}

System.out.println();

}

}

Theinput1object is constructed using the entire lowercase alphabet, whileinput2contains

only the first five letters. Here is the output:

input1 is:

abcdefghijklmnopqrstuvwxyz

input2 is:

abcde

CharArrayWriter

CharArrayWriteris an implementation of an output stream that uses an array as the destination.

CharArrayWriterhas two constructors, shown here: