Java中验证编码格式的一种方法

 package forlittlecatty;

 import java.io.File;
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.UnsupportedEncodingException;
 import java.util.Arrays;

 public class MainTest {

     public static void main(String[] args) {
         byte[] b1 = readByte(new File("./src/main/java/forlittlecatty/iso8859-1_en")); // 文件编码: ISO-8859-1 文件内容: "abc123!@#$%^&*()"
         byte[] b2 = readByte(new File("./src/main/java/forlittlecatty/utf-8_en_cn")); // 文件编码: UTF-8 文件内容: "abc123!@#$%^&*()小猫咪"
         byte[] b3 = readByte(new File("./src/main/java/forlittlecatty/gbk_en")); // 文件编码: GBK 文件内容: "abc123!@#$%^&*()"
         byte[] b4 = readByte(new File("./src/main/java/forlittlecatty/gbk_cn")); // 文件编码: GBK 文件内容: "小猫咪"
         System.out.println(isUTF8(b1)); // true
         System.out.println(isUTF8(b2)); // true
         System.out.println(isUTF8(b3)); // true
         System.out.println(isUTF8(b4)); // false
     }

     private static byte[] readByte(File file) {
         InputStream input = null;
         byte[] bytes = null;
         try {
             input = new FileInputStream(file);
             bytes = new byte[256];
             input.read(bytes);
         } catch (IOException e) {
             e.printStackTrace();
         } finally {
             try {
                 input.close();
             } catch (IOException e) {
                 e.printStackTrace();
             }
         }
         return bytes;
     }

     private static boolean isUTF8(byte[] src) {
         byte[] tmp = null;
         try {
             tmp = new String(src, "UTF-8").getBytes("UTF-8");
         } catch (UnsupportedEncodingException e) {
             e.printStackTrace();
         }
         return Arrays.equals(src, tmp);
     }
 }