CharArrayWriter类 示例

/*

CharArrayWriter 实现了以数组作为目标的输出流。CharArrayWriter 有两个构造函数：

CharArrayWriter( )

CharArrayWriter(int numChars)

第一种形式，创建了一个默认长度的缓冲器。第二种形式，缓冲器长度由numChars指定。缓冲器保存在CharArrayWriter的buf 成员中。缓冲器大小在需要的情况下可以自动增长。缓冲器保持的字符数包含在CharArrayWriter的count 成员中。buf 和count 都是受保护的域。

*/

//Demonstrate CharArrayWriter.
import java.io.*;
class CharArrayWriterDemo{
 public static void main(String[] args) throws IOException{
  CharArrayWriter f = new CharArrayWriter();
  String s = "This should end up in the array";
  char buf[] = new char[s.length()];
  s.getChars(0, s.length(), buf, 0);
  f.write(buf);
  System.out.println("Buffer as a string");
  System.out.println(f.toString());
  System.out.println("Into array");
  char c[] = f.toCharArray();
  for(int i=0;i<c.length;i++){
   System.out.print((char)c[i]);
  }
  System.out.println("\nTo a FileWriter()");

  FileWriter f2 = new FileWriter("test.txt");
  f.writeTo(f2);
  f2.close();

  System.out.println("Doing a reset");
  f.reset();
  for (int i=0; i<3; i++)
   f.write('X');
  System.out.println(f.toString());
 }
}