Java 识别TXT文档的编码方式

Java 判别TXT文档的编码方式
package com.zzy.code; import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.IOException;import java.io.InputStream;public class GetEncode {/*** @param args* @throws IOException *//*************************************  java编码与txt编码对应java txtunicode  unicode big endianutf-8 utf-8utf-16  unicodegb2312  ANSI***************************************/public static String getTxtType(File file) throws IOException {// TODO Auto-generated method stubInputStream inputStream=new FileInputStream(file);byte []head=new byte[3];inputStream.read(head);String code="";code="gb2312";if(head[0]==-1&&head[2]==-2){code="UTF-16";}if(head[0]==-2&&head[2]==-1){code="Unicode";}if(head[0]==-17&&head[2]==-69){code="UTF-8";}return code;}