Java如何進行Base64的編碼(Encode)與解碼(Decode)？

關於base64編碼Encode和Decode編碼的幾種方式

Base64是一種能將任意Binary資料用64種字元組合成字串的方法，而這個Binary資料和字串資料彼此之間是可以互相轉換的，十分方便。在實際應用上，Base64除了能將Binary資料可視化之外，也常用來表示字串加密過后的內容。如果要使用Java 程式語言來實作Base64的編碼與解碼功能，可以參考本篇文章的作法。

package edu;
import sun.misc.BASE64Encoder;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.io.UnsupportedEncodingException;
 
@SuppressWarnings("restriction")
public class Jiami {
    public static void main(String[] args) throws UnsupportedEncodingException {
        String userpwd= "jojo12525";
        MessageDigest sha1 = null;
        try {
            sha1 = MessageDigest.getInstance("SHA1");
        } catch (NoSuchAlgorithmException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        BASE64Encoder base64en = new BASE64Encoder();
        String pwd = base64en.encode(sha1.digest(userpwd.trim().getBytes("utf-8")));
        System.out.println(pwd);
    }
}

--------------------- 
作者：_calm 
來源：CSDN 
原文：https://blog.csdn.net/u011514810/article/details/72725398 
版權聲明：本文為博主原創文章，轉載請附上博文鏈接！

 

早期作法

早期在Java上做Base64的編碼與解碼，會使用到JDK里sun.misc套件下的BASE64Encoder和BASE64Decoder這兩個類別，用法如下：

final BASE64Encoder encoder = new BASE64Encoder(); final BASE64Decoder decoder = new BASE64Decoder(); final String text = "字串文字"; final byte[] textByte = text.getBytes("UTF-8"); //編碼 final String encodedText = encoder.encode(textByte); System.out.println(encodedText); //解碼 System.out.println(new String(decoder.decodeBuffer(encodedText), "UTF-8")); final BASE64Encoder encoder = new BASE64Encoder(); final BASE64Decoder decoder = new BASE64Decoder(); final String text = "字串文字"; final byte[] textByte = text.getBytes("UTF-8"); //編碼 final String encodedText = encoder.encode(textByte); System.out.println(encodedText); //解碼 System.out.println(new String(decoder.decodeBuffer(encodedText), "UTF-8"));

Apache Commons Codec作法

Apache Commons Codec有提供Base64的編碼與解碼功能，會使用到org.apache.commons.codec.binary套件下的Base64類別，用法如下：

final Base64 base64 = new Base64(); final String text = "字串文字"; final byte[] textByte = text.getBytes("UTF-8"); //編碼 final String encodedText = base64.encodeToString(textByte); System.out.println(encodedText); //解碼 System.out.println(new String(base64.decode(encodedText), "UTF-8")); final Base64 base64 = new Base64(); final String text = "字串文字"; final byte[] textByte = text.getBytes("UTF-8"); //編碼 final String encodedText = base64.encodeToString(textByte); System.out.println(encodedText); //解碼 System.out.println(new String(base64.decode(encodedText), "UTF-8"));
final Base64 base64 = new Base64(); final String text = "字串文字"; final byte[] textByte = text.getBytes("UTF-8"); //編碼 final String encodedText = base64.encodeToString(textByte); System.out.println(encodedText); //解碼 System.out.println(new String(base64.decode(encodedText), "UTF-8")); final Base64 base64 = new Base64(); final String text = "字串文字"; final byte[] textByte = text.getBytes("UTF-8"); //編碼 final String encodedText = base64.encodeToString(textByte); System.out.println(encodedText); //解碼 System.out.println(new String(base64.decode(encodedText), "UTF-8"));

以上的程式碼看起來又比早期用sun.mis c套件還要更精簡，效能實際執行起來也快了不少。缺點是需要引用Apache Commons Codec，很麻煩。

Java 8之后的作法

Java 8的java.util套件中，新增了Base64的類別，可以用來處理Base64的編碼與解碼，用法如下：

final Base64.Decoder decoder = Base64.getDecoder(); final Base64.Encoder encoder = Base64.getEncoder(); final String text = "字串文字"; final byte[] textByte = text.getBytes("UTF-8"); //編碼 final String encodedText = encoder.encodeToString(textByte); System.out.println(encodedText); //解碼 System.out.println(new String(decoder.decode(encodedText), "UTF-8")); final Base64.Decoder decoder = Base64.getDecoder(); final Base64.Encoder encoder = Base64.getEncoder(); final String text = "字串文字"; final byte[] textByte = text.getBytes("UTF-8"); //編碼 final String encodedText = encoder.encodeToString(textByte); System.out.println(encodedText); //解碼 System.out.println(new String(decoder.decode(encodedText), "UTF-8"));

 

package edu;import sun.misc.BASE64Encoder;import java.security.MessageDigest;import java.security.NoSuchAlgorithmException;import java.io.UnsupportedEncodingException; @SuppressWarnings("restriction")public class Jiami {public static void main(String[] args) throws UnsupportedEncodingException {String userpwd= "jojo12525";MessageDigest sha1 = null;try {sha1 = MessageDigest.getInstance("SHA1");} catch (NoSuchAlgorithmException e) {// TODO Auto-generated catch blocke.printStackTrace();}BASE64Encoder base64en = new BASE64Encoder();String pwd = base64en.encode(sha1.digest(userpwd.trim().getBytes("utf-8")));System.out.println(pwd);}}
--------------------- 作者：_calm 來源：CSDN 原文：https://blog.csdn.net/u011514810/article/details/72725398 版權聲明：本文為博主原創文章，轉載請附上博文鏈接！