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📜  Java 8-Base64

📅  最后修改于: 2021-01-05 04:42:25             🧑  作者: Mango

有了Java 8，Base64终于应有尽有。 Java 8现在具有用于Base64编码的内置编码器和解码器。在Java 8中，我们可以使用三种类型的Base64编码。

  • 简单-输出映射到A-Za-z0-9 + /中的一组字符。编码器不会在输出中添加任何换行符，并且解码器会拒绝除A-Za-z0-9 + /以外的任何字符。

  • URL-输出映射到A-Za-z0-9 + _中的字符集。输出是URL和文件名安全的。

  • MIME-输出被映射为MIME友好格式。输出以不超过76个字符的行表示，并使用回车符’\ r’和后跟换行符’\ n’作为行分隔符。在编码输出的末尾没有行分隔符。

嵌套类

Sr.No. Nested class & Description
1

static class Base64.Decoder

This class implements a decoder for decoding byte data using the Base64 encoding scheme as specified in RFC 4648 and RFC 2045.
2

static class Base64.Encoder

This class implements an encoder for encoding byte data using the Base64 encoding scheme as specified in RFC 4648 and RFC 2045.

方法

Sr.No. Method Name & Description
1

static Base64.Decoder getDecoder()

Returns a Base64.Decoder that decodes using the Basic type base64 encoding scheme.
2

static Base64.Encoder getEncoder()

Returns a Base64.Encoder that encodes using the Basic type base64 encoding scheme.
3

static Base64.Decoder getMimeDecoder()

Returns a Base64.Decoder that decodes using the MIME type base64 decoding scheme.
4

static Base64.Encoder getMimeEncoder()

Returns a Base64.Encoder that encodes using the MIME type base64 encoding scheme.
5

static Base64.Encoder getMimeEncoder(int lineLength, byte[] lineSeparator)

Returns a Base64.Encoder that encodes using the MIME type base64 encoding scheme with specified line length and line separators.
6

static Base64.Decoder getUrlDecoder()

Returns a Base64.Decoder that decodes using the URL and Filename safe type base64 encoding scheme.
7

static Base64.Encoder getUrlEncoder()

Returns a Base64.Encoder that encodes using the URL and Filename safe type base64 encoding scheme.

继承的方法

此类从以下类继承方法-

  • java.lang.Object

Base64示例

使用C：/> JAVA中选择的任何编辑器创建以下Java程序。

Java8Tester.java

现场演示
import java.util.Base64;
import java.util.UUID;
import java.io.UnsupportedEncodingException;

public class HelloWorld {

   public static void main(String args[]) {

      try {
        
         // Encode using basic encoder
         String base64encodedString = Base64.getEncoder().encodeToString(
            "TutorialsPoint?java8".getBytes("utf-8"));
         System.out.println("Base64 Encoded String (Basic) :" + base64encodedString);
        
         // Decode
         byte[] base64decodedBytes = Base64.getDecoder().decode(base64encodedString);
        
         System.out.println("Original String: " + new String(base64decodedBytes, "utf-8"));
         base64encodedString = Base64.getUrlEncoder().encodeToString(
            "TutorialsPoint?java8".getBytes("utf-8"));
         System.out.println("Base64 Encoded String (URL) :" + base64encodedString);
        
         StringBuilder stringBuilder = new StringBuilder();
        
         for (int i = 0; i < 10; ++i) {
            stringBuilder.append(UUID.randomUUID().toString());
         }
        
         byte[] mimeBytes = stringBuilder.toString().getBytes("utf-8");
         String mimeEncodedString = Base64.getMimeEncoder().encodeToString(mimeBytes);
         System.out.println("Base64 Encoded String (MIME) :" + mimeEncodedString);

      } catch(UnsupportedEncodingException e) {
         System.out.println("Error :" + e.getMessage());
      }
   }
}

验证结果

使用javac编译器编译类，如下所示：

C:\JAVA>javac Java8Tester.java

现在如下运行Java8Tester-

C:\JAVA>java Java8Tester

它应该产生以下输出-

Base64 Encoded String (Basic) :VHV0b3JpYWxzUG9pbnQ/amF2YTg=
Original String: TutorialsPoint?java8
Base64 Encoded String (URL) :VHV0b3JpYWxzUG9pbnQ_amF2YTg=
Base64 Encoded String (MIME) :YmU3NWY2ODktNGM5YS00ODlmLWI2MTUtZTVkOTk2YzQ1Njk1Y2EwZTg2OTEtMmRiZC00YTQ1LWJl
NTctMTI1MWUwMTk0ZWQyNDE0NDAwYjgtYTYxOS00NDY5LTllYTctNjc1YzE3YWJhZTk1MTQ2MDQz
NDItOTAyOC00ZWI0LThlOTYtZWU5YzcwNWQyYzVhMTQxMWRjYTMtY2MwNi00MzU0LTg0MTgtNGQ1
MDkwYjdiMzg2ZTY0OWU5MmUtZmNkYS00YWEwLTg0MjQtYThiOTQxNDQ2YzhhNTVhYWExZjItNjU2
Mi00YmM4LTk2ZGYtMDE4YmY5ZDZhMjkwMzM3MWUzNDMtMmQ3MS00MDczLWI0Y2UtMTQxODE0MGU5
YjdmYTVlODUxYzItN2NmOS00N2UyLWIyODQtMThlMWVkYTY4M2Q1YjE3YTMyYmItZjllMS00MTFk
LWJiM2UtM2JhYzUxYzI5OWI4