从TXT中获取类列表，然后从文件夹rt中复制这些类，拷贝到文件夹rt1中

类列表类似：

sun/misc/JavaSecurityAccess java/security/AccessControlContext$1 java/nio/charset/Charset$3

工具类（转载自 作者）：

package com.ciotea.hosts;import java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStreamReader;import java.io.LineNumberReader;public class ReduceRt {	// 文件拷贝	public static boolean copy(String file1, String file2) {		try // must try and catch,otherwide will compile error		{			// instance the File as file_in and file_out			java.io.File file_in = new java.io.File(file1);			java.io.File file_out = new java.io.File(file2);			FileInputStream in1 = new FileInputStream(file_in);			FileOutputStream out1 = new FileOutputStream(file_out);			byte[] bytes = new byte[1024];			int c;			while ((c = in1.read(bytes)) != -1)				out1.write(bytes, 0, c);			in1.close();			out1.close();			return (true); // if success then return true		} catch (Exception e) {			System.out.println("Error!");			return (false); // if fail then return false		}	}	// 读取路径,copy	public static int dealClass(String needfile, String sdir, String odir) throws IOException {		int sn = 0; // 成功个数		File usedclass = new File(needfile);		if (usedclass.canRead()) {			String line = null;			LineNumberReader reader = new LineNumberReader(					new InputStreamReader(new FileInputStream(usedclass), "UTF-8"));			while ((line = reader.readLine()) != null) {				line = line.trim();				int dirpos = line.lastIndexOf("/");				if (dirpos > 0) {					String dir = odir + line.substring(0, dirpos);					File fdir = new File(dir);					if (!fdir.exists())						fdir.mkdirs();					String sf = sdir + line + ".class";					String of = odir + line + ".class";					boolean copy_ok = copy(sf.trim(), of.trim());					if (copy_ok)						sn++;					else {						System.out.println(line);					}				}			}		}		return sn;	}	public static void main(String[] args) {		String needfile = System.getProperty("user.dir")+"\\usedclass.txt";		String sdir = System.getProperty("user.dir")+"/rt/";		String odir = System.getProperty("user.dir")+"/rt1/";		try {			int sn = dealClass(needfile, sdir, odir);			System.out.print(sn);		} catch (IOException e) {			// TODO 自动生成 catch 块			e.printStackTrace();		}	}}