解码和编码问题。android.util.* 和 java.util.* 中 Base64 类的不同实现？
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Decoding and Encoding issue. Different implementations of Base64 Class in android.util.* and java.util.*?
提问by user3469811
I am writing an App which does the following with a given String str:
我正在编写一个应用程序，它使用给定的字符串 str 执行以下操作：
encode(encrypt(encode(stringToBytearray(str))));
The Server receives the Base64 encoded String, which is then decoded -> decrypted -> decoded, to get the sent String str from the App.
Server接收Base64编码的String，然后解码->解密->解码，得到App发送的String str。
Unfortunately it doesnt work for all Strings, long Strings lead to a long Base64 String and my Server throws the following Exception:
不幸的是，它不适用于所有字符串，长字符串导致长 Base64 字符串，我的服务器抛出以下异常：
Exception in thread "main" java.lang.IllegalArgumentException: Illegal base64 character 5b
at java.util.Base64$Decoder.decode0(Base64.java:714)
at java.util.Base64$Decoder.decode(Base64.java:526)
at Main.decode(Main.java:113)
at Main.main(ain.java:33)
The String has the format "[string, string, ..., string]" without "s.
String 的格式为“[string, string, ..., string]”，没有“s”。
Like I mentioned above, for Strings which are not too long (sorry I cant quantify the length yet), this works. So I think I implemented it right.
就像我上面提到的，对于不太长的字符串（对不起，我还不能量化长度），这是有效的。所以我认为我实施它是正确的。
Whats weird is, that if I dont send it, but decode(decrypt(decode(stringToBytearray(str)))); the String on the Device itself, it all works perfectly.
奇怪的是，如果我不发送它，而是 decode(decrypt(decode(stringToBytearray(str)))); 设备本身上的字符串，一切都完美无缺。
My Setup: JDK 7, eclipse (adt-bundle, android development) (Windows 7)
我的设置：JDK 7，eclipse（adt-bundle，android 开发）（Windows 7）
JDK 8, eclipse ('normal' java) (Linux (xubuntu))
JDK 8, eclipse ('normal' java) (Linux (xubuntu))
Is it because both Classes (Base64) are implemented diffrently? If so, how can I make it work?
是因为两个类（Base64）的实现方式不同吗？如果是这样，我怎样才能使它工作？
Here are the Encoding/Decoding Methods:
以下是编码/解码方法：
Encoding (Device: on Windows 7, adt-bundle, Android-Dev, jdk 7):
编码（设备：Windows 7、adt-bundle、Android-Dev、jdk 7）：
import android.util.Base64
public byte[] encode(byte[] bytearrayToEncode){
return Base64.encode(bytearrayToEncode, Base64.NO_WRAP|Base64.URL_SAFE);
}
Decoding (Server: on Linux, jdk 8):
解码（服务器：Linux，jdk 8）：
import java.util.Base64
public byte[] decode(byte[] bytearrayToEncode){
return Base64.getUrlDecoder().decode(bytearrayToDecode);
}
Strings are all De-/Encoded with the same charset (utf-8)! Encoding/Decoding: Base64
字符串都使用相同的字符集 (utf-8) 进行解码/编码！编码/解码：Base64
Crypto: AES
加密：AES
If you need more Information, just ask, but I think I provided all neccessary informations.
如果您需要更多信息，请问，但我想我提供了所有必要的信息。
Edit:
编辑：
public String bytearrayToString(byte[] bytearray){
String str = null;
try {
str = new String(bytearray, "UTF-8");
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return str;
}
public byte[] stringToBytearray(String str){
byte[] bytearray = null;
try {
bytearray = str.getBytes("UTF-8");
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return bytearray;
}
回答by Mohsin Ali
You must be using JSONObjects to send the Base64 String to the server. If so then the JSONObject will add " \ " escape characters to the string which are illegal Base64 characters. All you need to do is
您必须使用 JSONObjects 将 Base64 字符串发送到服务器。如果是这样，那么 JSONObject 将向字符串添加“\”转义字符，这些字符是非法 Base64 字符。你需要做的就是
String rectifiedString = Base64String.replace("\","");
on the server end before using the acquired string.
在使用获取的字符串之前在服务器端。
Optional
可选的
Also on the server side use
也在服务器端使用
import javax.xml.bind.DatatypeConverter;
and
和
String result = DatatypeConverter.printBase64Binary(bytearrayToDecode);
String result = DatatypeConverter.printBase64Binary(bytearrayToDecode);
byte[] result = DatatypeConverter.parseBase64Binary(str);
instead.
反而。
It will not only get the job done but is much faster at encoding/decoding (as benchmarked here).
它不仅可以完成工作，而且在编码/解码方面要快得多（如此处的基准测试）。
回答by Anand Varkey Philips
If you have a space in your encoded string, which is an illegal character in base64. If you remove it, it still generates the same image/data in the converter you linked to, and can be now decoded by your code as well.
如果编码字符串中有空格，这是 base64 中的非法字符。如果您删除它，它仍然会在您链接到的转换器中生成相同的图像/数据，并且现在也可以通过您的代码进行解码。
UPDATE:Some decoders (like the one you linked, or Base64.getMimeDecoder() in Java) ignore illegal characters, others (like Base64.getDecoder()) don't allow them.
更新：一些解码器（比如你链接的那个，或者 Java 中的 Base64.getMimeDecoder()）忽略非法字符，其他的（比如 Base64.getDecoder()）不允许它们。
回答by Leonardo Borges
Use for encode:
用于编码：
Base64.getEncoder().encodeToString(yourString.getBytes("UTF-8"));
and decode:
并解码：
byte[] decodedBytes = Base64.getDecoder().decode(yourString);
String stringDecode = new String(decodedBytes, "UTF-8");
