java中Base64编码与解码
文章目录
一、Base64简介
Base64是一种编码与解码方式,用于将二进制数据编码为64个可打印字符,或者相反操作。
二、知识点
2.1 Base64字符
Base64有64个可打印字符,包括:A-Z,a-z,0-9,+,/,它们的编码分别从0到63。
2.2 Base64实现
Base64内部实现是:将二进制流以6位分组,然后每个分组高位补2个0(计算机是8位存数),这样每个组值就是在64以内,然后转为对应的编码。
三、实例
3.1 jdk原生实现
实现方式一,借助jdk自身的BASE64Encoder和BASE64Decoder,示例如下:
public class Base64Main {
public static void main(String[] args) throws Exception {
String source = "study hard and make progress everyday";
System.out.println("source : "+ source);
String result = base64Encode(source.getBytes("utf8")); //编码
System.out.println("encode result : " + result);
String rawSource = new String(base64Decode(result),"utf8"); //解码
System.out.println("decode result : "+ rawSource);
}
//编码
static String base64Encode(byte[] source) {
BASE64Encoder encoder = new BASE64Encoder();
return encoder.encode(source);
}
//解码
static byte[] base64Decode(String source){
try {
BASE64Decoder decoder = new BASE64Decoder();
return decoder.decodeBuffer(source);
} catch (IOException e) {
}
return null;
}
}
运行结果:
source : study hard and make progress everyday
encode result : c3R1ZHkgaGFyZCBhbmQgbWFrZSBwcm9ncmVzcyBldmVyeWRheQ==
decode result : study hard and make progress everyday
3.2 commons-codec包实现
实现方式二,借助commons-codec包,示例如下:
添加maven依赖:
<dependency>
<groupId>commons-codec</groupId>
<artifactId>commons-codec</artifactId>
<version>1.10</version>
</dependency>
代码:
public class Base64FromCommonsMain {
public static void main(String[] args) throws Exception {
String source = "study hard and make progress everyday";
System.out.println("source : "+ source);
String result = Base64.encodeBase64String(source.getBytes("utf8")); //编码
System.out.println("encode result : " + result);
String rawSource = new String(Base64.decodeBase64(result),"utf8"); //解码
System.out.println("decode result : "+ rawSource);
}
}
运行结果:
source : study hard and make progress everyday
encode result : c3R1ZHkgaGFyZCBhbmQgbWFrZSBwcm9ncmVzcyBldmVyeWRheQ==
decode result : study hard and make progress everyday