Native2Ascii文件转换 -- 待完善

摘自：https://www.oschina.net/code/snippet_87799_1612

Native2Ascii文件转换 -- 待完善

 package com.xxx.xxx.Util;

 import java.io.BufferedReader;
 import java.io.BufferedWriter;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.io.OutputStreamWriter;

 /**
  * 类、接口等说明
  *
  * @Date
  * @version v1.0
  * @author 　　
  */
 public class ConvertFileNative2ASCIIUtil {

     public static boolean native2Ascii(String srcFileName, String srcFilecharsetName, String dstFileName,
             String dstFilecharsetName) throws IOException {

         File srcFileNameFile = new File(srcFileName);

         if (!srcFileNameFile.exists()) {
             throw new IOException(" File(" + srcFileName + ") Parameter does not reference a file that exists");
         } else if (!srcFileNameFile.isFile()) {
             throw new IOException("File(" + srcFileName + ") Parameter exists, but does not reference a file");
         } else if (!srcFileNameFile.canRead()) {
             throw new IOException("File(" + srcFileName + ") exists and is a file, but cannot be read.");
         } else {
             String content = readFile(srcFileName, srcFilecharsetName);
             String ascii = Native2ASCIIUtil.native2Ascii(content);
             writeFile(dstFileName, ascii, dstFilecharsetName);
         }

         return true;
     }

     public static boolean ascii2Native(String srcFileName, String srcFilecharsetName, String dstFileName,
             String dstFilecharsetName) throws IOException {

         File srcFileNameFile = new File(srcFileName);

         if (!srcFileNameFile.exists()) {
             throw new IOException(" File(" + srcFileName + ") Parameter does not reference a file that exists");
         } else if (!srcFileNameFile.isFile()) {
             throw new IOException("File(" + srcFileName + ") Parameter exists, but does not reference a file");
         } else if (!srcFileNameFile.canRead()) {
             throw new IOException("File(" + srcFileName + ") exists and is a file, but cannot be read.");
         } else {
             String content = readFile(srcFileName, srcFilecharsetName);
             String nativeString = Native2ASCIIUtil.ascii2Native(content);
             writeFile(dstFileName, nativeString, dstFilecharsetName);
         }

         return true;
     }

     public static void writeFile(String path, String content, String encoding) throws IOException {
         File file = new File(path);
         file.delete();
         file.createNewFile();
         BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file), encoding));
         writer.write(content);
         writer.close();
     }

     public static String readFile(String path, String encoding) throws IOException {
         String content = "";
         File file = new File(path);
         BufferedReader reader = new BufferedReader(new InputStreamReader(new FileInputStream(file), encoding));
         String line = null;
         while ((line = reader.readLine()) != null) {
             content += line + "\n";
         }
         reader.close();
         return content;
     }
 }

 package com.xxx.xxx.Util;

 /**
  * 类、接口等说明
  *
  * @Date
  * @version v1.0
  * @author
  */
 public class Native2ASCIIUtil {

     /**
      * prefix of ascii string of native character
      */
     private static String PREFIX = "\\u";

     /**
      * Native to ascii string. It's same as execut native2ascii.exe.
      * @param str native string
      * @return ascii string
      */
     public static String native2Ascii(String str) {
         char[] chars = str.toCharArray();
         StringBuilder sb = new StringBuilder();
         for (int i = 0; i < chars.length; i++) {
             sb.append(char2Ascii(chars[i]));
         }
         return sb.toString();
     }

     /**
      * Native character to ascii string.
      * @param c native character
      * @return ascii string
      */
     private static String char2Ascii(char c) {
         if (c > 255) {
             StringBuilder sb = new StringBuilder();
             sb.append(PREFIX);
             int code = (c >> 8);
             String tmp = Integer.toHexString(code);
             if (tmp.length() == 1) {
                 sb.append("0");
             }
             sb.append(tmp);
             code = (c & 0xFF);
             tmp = Integer.toHexString(code);
             if (tmp.length() == 1) {
                 sb.append("0");
             }
             sb.append(tmp);
             return sb.toString();
         } else {
             return Character.toString(c);
         }
     }

     /**
      * Ascii to native string. It's same as execut native2ascii.exe -reverse.
      * @param str ascii string
      * @return native string
      */
     public static String ascii2Native(String str) {
         StringBuilder sb = new StringBuilder();
         int begin = 0;
         int index = str.indexOf(PREFIX);
         while (index != -1) {
             sb.append(str.substring(begin, index));
             sb.append(ascii2Char(str.substring(index, index + 6)));
             begin = index + 6;
             index = str.indexOf(PREFIX, begin);
         }
         sb.append(str.substring(begin));
         return sb.toString();
     }

     /**
      * Ascii to native character.
      * @param str ascii string
      * @return native character
      */
     private static char ascii2Char(String str) {
         if (str.length() != 6) {
             throw new IllegalArgumentException("Ascii string of a native character must be 6 character.");
         }
         if (!PREFIX.equals(str.substring(0, 2))) {
             throw new IllegalArgumentException("Ascii string of a native character must start with \"\\u\".");
         }
         String tmp = str.substring(2, 4);
         int code = Integer.parseInt(tmp, 16) << 8;
         tmp = str.substring(4, 6);
         code += Integer.parseInt(tmp, 16);
         return (char) code;
     }
 }