1 package 内存流;
 2 
 3 import java.io.ByteArrayInputStream;
 4 import java.io.ByteArrayOutputStream;
 5 import java.io.IOException;
 6 import java.io.InputStream;
 7 import java.io.OutputStream;
 8 
 9 public class Test {
10     public static void main(String[] args) throws IOException {
11         String str="Hello World!中国好国国国。";
12         InputStream in=new ByteArrayInputStream(str.getBytes());
13         OutputStream out=new ByteArrayOutputStream();
14         int tmp=0;
15         while((tmp=in.read())!=-1)
16             out.write(Character.toUpperCase(tmp));
17         System.out.println(out);//HELLO WORLD!中冠好冠冠冠。
18         //中文有乱码！！！
19         in.close();
20         out.close();
21     }
22 }

 1 package 内存流;
 2 
 3 import java.io.CharArrayReader;
 4 import java.io.CharArrayWriter;
 5 import java.io.IOException;
 6 import java.io.Reader;
 7 import java.io.Writer;
 8 
 9 public class Test {
10     public static void main(String[] args) throws IOException {
11         String str="Hello World!中国好国国国。";
12         Reader in=new CharArrayReader(str.toCharArray());
13         Writer out=new CharArrayWriter();
14         int tmp=0;
15         while((tmp=in.read())!=-1)
16             out.write(Character.toUpperCase(tmp));
17         System.out.println(out);//HELLO WORLD!中国好国国国。
18         //字符流处理中文无乱码！！！
19         in.close();
20         out.close();
21     }
22 }