出现原因：FileReader读取文件的过程中，FileReader继承了InputStreamReader，但并没有实现父类中带字符集参数的构造函数，所以FileReader只能按系统默认的字符集来解码，然后在UTF-8 -> GBK -> UTF-8的过程中编码出现损失，造成结果不能还原最初的字符。

/** * 获得文件内容 * @param file * @return*/public String getFileContent(File file){				InputStreamReader reader = null;		StringBuffer result = new StringBuffer();		try {			reader = new InputStreamReader(new FileInputStream(file),"gbk");						int ch = reader.read();			while(ch != -1){				result.append((char)ch);				ch = reader.read();			}			reader.close();		} catch (Exception e) {			e.printStackTrace();			reader = null;		}		return result.toString();	}

 FileReader和FileWriter的使用：可用于己知输入编码和输出编码情况下：

public List
     
       getFileContent(){				List
      
        list = new ArrayList
       
        ();				File f = null;		BufferedReader buff = null;		BufferedWriter out = null;                StringBuffer buffer = new StringBuffer();		try {			f = new File("resource/domain0108.csv");			buff = new BufferedWriter(new FileWriter(f));						String temp = buff.readLine();			while(true){				if(temp == null){					break;				}				/*byte[] bb = temp.getBytes("utf-8");				temp = new String(bb,"gbk");*/				list.add(temp + "\r\n");                                buffer.append(temp + "\r\n");				temp = buff.readLine();			}			System.out.println("InfoPorcesser.getFileContent返回文件内容列表成功"+list.size());                        out.write(buffer.toString());                        out.flush();                        out.close();			buff.close();		} catch (Exception e) {			e.printStackTrace();			buff = null;		}				return list;	}