複製文件

/*
將一個文件複製到另外一個文件
*/
package copyDemo;
import java.io.*;
class CopyDemo 
{
	public static void main(String[] args) 
	{
		copy2();
	}
	//用數組的方式讀取
	public static void copy2()
	{
		FileReader fr=null;
		FileWriter fw=null;
		try
		{
			fr=new FileReader("CalendarDemo.java");
			fw=new FileWriter("CalendarDemo_copy.java");
			char[] chs=new char[1024];
			int len=0;
			while((len=fr.read(chs))!=-1)
			{
				fw.write(chs,0,len);
			}
		}
		catch (IOException e)
		{
			throw new RuntimeException("讀取失敗");
		}
		finally
		{
			try
			{
				if(fr!=null)
					fr.close();
			}
			catch (IOException e)
			{
				System.out.println(e.toString());
			}
			try
			{
				if(fw!=null)
					fw.close();
			}
			catch (IOException e)
			{
				System.out.println(e.toString());
			}
		}
	}
	//讀一個，寫一個
	public static void copy1()
	{
		FileWriter fw=null;
		FileReader fr=null;
		try
		{
			fw=new FileWriter("Test_copy.java");
			fr=new FileReader("Test.java");
			int ch=0;
			while((ch=fr.read())!=-1)
			{
				fw.write(ch);
			}
		}
		catch (IOException e)
		{
			throw new RuntimeException("讀取失敗");
		}
		finally
		{
			try
			{
				if(fw!=null)
				fw.close();
			}
			catch (IOException e)
			{
				System.out.println(e.toString());
			}
			try
			{
				if(fr!=null)
					fr.close();
			}
			catch (IOException e)
			{
				System.out.println(e.toString());
			}
		}
	}
}