changecaseinputstream.java

此代码完成对输入流的装饰模式。可以输出自己想要的形式。

import java.io.*;
import java.util.*;
/*exteands from the FilterInputStream*/
public class changeCaseInputStream extends FilterInputStream
{
	InputStream input;
	/*constructer*/
	public changeCaseInputStream (InputStream in)
	{

		super(in);
		/*init input*/
		this.input=in;
	}
	/*decorate the function read()*/
	public int read() throws IOException
	{
		int c=input.read();
		if(65<=c&&c<=90)
		{
			return Character.toLowerCase((char)c);
		}
		else if(97<=c&&c<=122)
		{
			return Character.toUpperCase((char)c);
		}
		else
		{
			return c;
		}
	}
	/*decorate the function read(byte,int,int)*/
	public int read(byte[]byt,int offset,int len) throws IOException
	{
		int result =input.read(byt,offset,len);
		for(int i=offset;i<offset+result;i++)
		{
			if(65<=byt[i]&&byt[i]<=90)
			{
				byt[i]=(byte)Character.toLowerCase((char)byt[i]);
			}
			else if(97<=byt[i]&&byt[i]<=122)
			{
				byt[i]=(byte)Character.toUpperCase((char)byt[i]);
			}
		}
		return result;
	}
}