base64coder调用

base64coder 可以查看官网：   http://www.source-code.biz/base64coder/java/

我所涉及到的  base64coder调用：

某天，因需要修改Properties文件中的部分内容，而该内容是base64做过加密的，所有要进行解密、修改、加密、存储，

主要对 gui_preferences 中的color 进行修改,gui_preferences 在Properties文件中如下：   

gui_preferences = 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

这个Color对象就存在此密文中【红色部分及目标】，所以得解密然后才能看到，我把解密后的内容列出来供对比，

app_preferences_revision:1
app_border_width:2
app_scrollbar_width:small
app_panel_font:java.awt.Font[family=Tahoma,name=Tahoma,style=plain,size=10]
app_title_foreground:java.awt.Color[r=255,g=255,b=255]
app_border_color:java.awt.Color[r=137,g=137,b=137]
app_gradient_min:java.awt.Color[r=179,g=238,b=58]
app_title_font:java.awt.Font[family=Arial,name=Arial,style=bold,size=12]
app_gradient_max:java.awt.Color[r=185,g=211,b=238]
app_color_scheme:selfDesing

涉及 ：base64加密解密，对象序列化

以下为此过程，另附  base64coder 文件。

一调用过程：

 import java.awt.Color;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.ObjectInputStream;
 import java.io.ObjectOutputStream;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.Properties;

 /**
  * @author yang
  * @category
  * @see http://www.114la.com/other/rgb.htm
  */

 public class Do {

     public static void main(String[] args) {

         //1 read propriety
         String filepath="D:\\ec.properties";

         //-----------------gui_preferences--------------
         String gui_preferences="gui_preferences";
         Color color_gradient_min=new Color(179,238,58);
         Color color_gradient_max=new Color(185,211,238);
         String color_gradient_scheme="selfDesing";
         //-----------------gui_preferences--------------

         Properties pro=new  Properties();
         try {
             pro.load(new FileInputStream(new File(filepath)));
         } catch (FileNotFoundException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         } catch (IOException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }
          ///gui_preferences
         System.out.println(pro.getProperty(gui_preferences));
         String tempstr=pro.getProperty(gui_preferences);

         //2 decode
         //HashMap hm=new HashMap();
         HashMap hm=Do.getMapFromString(tempstr);
         Iterator t=hm.keySet().iterator(); 

         //3 modify
         while(t.hasNext()){

            String s=(String) t.next();
          //  System.out.println(s+":"+hm.get(s));
            if(s.equals("app_gradient_min"))
            {
                hm.put("app_gradient_min", color_gradient_min);
            }
            if(s.equals("app_gradient_max"))
            {
                hm.put("app_gradient_max", color_gradient_max);
            }
            if(s.equals("app_color_scheme"))
            {
                hm.put("app_color_scheme", color_gradient_scheme);
            }
        }

         //print
         //        Iterator i=hm.keySet().iterator();
         //
         //        while(i.hasNext()){
         //           String s=(String) i.next();
         //           System.out.println(s+":"+hm.get(s));
         //         }

         //4 encode
         if(hm!=null && hm.size()>0){
                 try {
                     pro.setProperty(gui_preferences,getStringFromObject(hm));
                 } catch (IOException e) {
                     // TODO Auto-generated catch block
                     e.printStackTrace();
                 }
         }

        //5 save
         try {
             pro.store(new FileOutputStream(new File(filepath)), "");
         } catch (FileNotFoundException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         } catch (IOException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }

     }

      private static Object getObjectFromString(String value) throws IOException, ClassNotFoundException, IOException {
             Object obj = null;
             ByteArrayOutputStream out = new ByteArrayOutputStream();
             ByteArrayInputStream bin = new ByteArrayInputStream(value.getBytes());
             Base64Coder.decodeStream(bin, out);

             bin = new ByteArrayInputStream(out.toByteArray());
             ObjectInputStream is = new ObjectInputStream(bin);
             obj = is.readObject();

             return obj;
         }

      public static HashMap getMapFromString(String value) {
             HashMap map = null;
             if (value != null) {
                 try {
                     Object obj = getObjectFromString(value);
                     if (obj != null) {
                         if (obj instanceof HashMap) {
                             map = (HashMap) obj;
                         }
                     }

                 } catch (Exception ex) {
                     //logger.log(Level.SEVERE, "Can't get hash map from string: " + value, ex);
                     System.out.println("Can't get hash map from string: " +   ex);
                 }
             }
             return map;
         }

       public static String getStringFromObject(Object obj) throws IOException {
             String str = null;
             ByteArrayOutputStream out = new ByteArrayOutputStream();
             ObjectOutputStream os = new ObjectOutputStream(out);
             os.writeObject(obj);
             ByteArrayInputStream bin = new ByteArrayInputStream(out.toByteArray());
             out.reset();
             //Base64Encoder be = new Base64Encoder(bin, out);
             Base64Coder.encodeStream(bin, out);
             str = out.toString();
             return str;
         }
 }

二 base64coder 文件

/**
 * A Base64 Encoder/Decoder.
 *
 * <p>
 * This class is used to encode and decode data in Base64 format as described in RFC 1521.
 *
 * <p>
 * This is "Open Source" software and released under the <a href="http://www.gnu.org/licenses/lgpl.html">GNU/LGPL</a> license.<br>
 * It is provided "as is" without warranty of any kind.<br>
 * Copyright 2003: Christian d'Heureuse, Inventec Informatik AG, Switzerland.<br>
 * Home page: <a href="http://www.source-code.biz">www.source-code.biz</a><br>
 *
 * <p>
 * Version history:<br>
 * 2003-07-22 Christian d'Heureuse (chdh): Module created.<br>
 * 2005-08-11 chdh: Lincense changed from GPL to LGPL.<br>
 * 2006-11-21 chdh:<br>
 *  &nbsp; Method encode(String) renamed to encodeString(String).<br>
 *  &nbsp; Method decode(String) renamed to decodeString(String).<br>
 *  &nbsp; New method encode(byte[],int) added.<br>
 *  &nbsp; New method decode(String) added.<br>
 */

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

public class Base64Coder {

// Mapping table from 6-bit nibbles to Base64 characters.
    private static char[] map1 = new char[64];

    static {
        int i = 0;
        for (char c = 'A'; c <= 'Z'; c++) {
            map1[i++] = c;
        }
        for (char c = 'a'; c <= 'z'; c++) {
            map1[i++] = c;
        }
        for (char c = '0'; c <= '9'; c++) {
            map1[i++] = c;
        }
        map1[i++] = '+';
        map1[i++] = '/';
    }

// Mapping table from Base64 characters to 6-bit nibbles.
    private static byte[] map2 = new byte[128];

    static {
        for (int i = 0; i < map2.length; i++) {
            map2[i] = -1;
        }
        for (int i = 0; i < 64; i++) {
            map2[map1[i]] = (byte) i;
        }
    }

    /**
     * Encodes a string into Base64 format.
     * No blanks or line breaks are inserted.
     * @param s  a String to be encoded.
     * @return   A String with the Base64 encoded data.
     */
    public static String encodeString(String s) {
        return new String(encode(s.getBytes()));
    }

    /**
     * Encodes a byte array into Base64 format.
     * No blanks or line breaks are inserted.
     * @param in  an array containing the data bytes to be encoded.
     * @return    A character array with the Base64 encoded data.
     */
    public static char[] encode(byte[] in) {
        return encode(in, in.length);
    }

    /**
     * Encodes a byte array into Base64 format.
     * No blanks or line breaks are inserted.
     * @param in   an array containing the data bytes to be encoded.
     * @param iLen number of bytes to process in <code>in</code>.
     * @return     A character array with the Base64 encoded data.
     */
    public static char[] encode(byte[] in, int iLen) {
        int oDataLen = (iLen * 4 + 2) / 3;       // output length without padding
        int oLen = ((iLen + 2) / 3) * 4;         // output length including padding
        char[] out = new char[oLen];
        int ip = 0;
        int op = 0;
        while (ip < iLen) {
            int i0 = in[ip++] & 0xff;
            int i1 = ip < iLen ? in[ip++] & 0xff : 0;
            int i2 = ip < iLen ? in[ip++] & 0xff : 0;
            int o0 = i0 >>> 2;
            int o1 = ((i0 & 3) << 4) | (i1 >>> 4);
            int o2 = ((i1 & 0xf) << 2) | (i2 >>> 6);
            int o3 = i2 & 0x3F;
            out[op++] = map1[o0];
            out[op++] = map1[o1];
            out[op] = op < oDataLen ? map1[o2] : '=';
            op++;
            out[op] = op < oDataLen ? map1[o3] : '=';
            op++;
        }
        return out;
    }

    /**
     * Decodes a string from Base64 format.
     * @param s  a Base64 String to be decoded.
     * @return   A String containing the decoded data.
     * @throws   IllegalArgumentException if the input is not valid Base64 encoded data.
     */
    public static String decodeString(String s) {
        return new String(decode(s));
    }

    /**
     * Decodes a byte array from Base64 format.
     * @param s  a Base64 String to be decoded.
     * @return   An array containing the decoded data bytes.
     * @throws   IllegalArgumentException if the input is not valid Base64 encoded data.
     */
    public static byte[] decode(String s) {
        return decode(s.toCharArray());
    }

    /**
     * Decodes a byte array from Base64 format.
     * No blanks or line breaks are allowed within the Base64 encoded data.
     * @param in  a character array containing the Base64 encoded data.
     * @return    An array containing the decoded data bytes.
     * @throws    IllegalArgumentException if the input is not valid Base64 encoded data.
     */
    public static byte[] decode(char[] in) {
        int iLen = in.length;
        if (iLen % 4 != 0) {
            throw new IllegalArgumentException("Length of Base64 encoded input string is not a multiple of 4.");
        }
        while (iLen > 0 && in[iLen - 1] == '=') {
            iLen--;
        }
        int oLen = (iLen * 3) / 4;
        byte[] out = new byte[oLen];
        int ip = 0;
        int op = 0;
        while (ip < iLen) {
            int i0 = in[ip++];
            int i1 = in[ip++];
            int i2 = ip < iLen ? in[ip++] : 'A';
            int i3 = ip < iLen ? in[ip++] : 'A';
            if (i0 > 127 || i1 > 127 || i2 > 127 || i3 > 127) {
                throw new IllegalArgumentException("Illegal character in Base64 encoded data.");
            }
            int b0 = map2[i0];
            int b1 = map2[i1];
            int b2 = map2[i2];
            int b3 = map2[i3];
            if (b0 < 0 || b1 < 0 || b2 < 0 || b3 < 0) {
                throw new IllegalArgumentException("Illegal character in Base64 encoded data.");
            }
            int o0 = (b0 << 2) | (b1 >>> 4);
            int o1 = ((b1 & 0xf) << 4) | (b2 >>> 2);
            int o2 = ((b2 & 3) << 6) | b3;
            out[op++] = (byte) o0;
            if (op < oLen) {
                out[op++] = (byte) o1;
            }
            if (op < oLen) {
                out[op++] = (byte) o2;
            }
        }
        return out;
    }

    public static void decodeStream(InputStream in, OutputStream out) throws IOException {
            String s = inputStreamToString(in);
            byte[] buf = decode(s);
            out.write(buf);
    }

    public static String inputStreamToString(InputStream in) throws IOException {
        StringBuffer out = new StringBuffer();
        byte[] b = new byte[4096];
        for (int n; (n = in.read(b)) != -1;) {
            out.append(new String(b, 0, n));
        }
        return out.toString();
    }

    public static void encodeStream(InputStream in, OutputStream out) throws IOException {
        int lineLength = 72;
        byte[] buf = new byte[lineLength / 4 * 3];
        while (true) {
            int len = in.read(buf);
            if (len <= 0) {
                break;
            }
            String str = new String(encode(buf, len));
            out.write(str.getBytes());
        }

    }
// Dummy constructor.
    private Base64Coder() {
    }
} // end class Base64Coder