Java進行中文亂碼

進行中文亂碼： 

File file = new File(fileName);
Long filelength = file.length();  
byte[] filecontent = new byte[filelength.intValue()];
FileInputStream in = new FileInputStream(file);
in.read(filecontent);
in.close();
String content = new String(filecontent, "UTF-8");