java 64进制字符串如何转为字节数组

Question

如题，图片是以64进制字符串存储的，我要把它转为 byte[] 输出到页面显示，如何转换呢？字符串例如：
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Answer 1

上面的例子字符串没显示全，字符串的尾部是两个等号(=)
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Answer 2

  java 有个类是处理这个的，用base64解码就可以了，我用他做过存储视频的,byte[] bs = new BASE64Decoder().decodeBuffer(sbf.toString());将得到的bs输出就可以了，你所列出的字符串要整的，不能分开处理，不然会不能显示

Answer 3

如果用sun.misc.BASE64Decoder，
编译的时候警告，sun.misc.BASE64Decoder is Sun proprietary API and may be removed in a future release。我使用 org.bouncycastle.util.encoders.Base64，工程的 jar 包里包含这个类，我却一直不知道！Base64.decode(str64Data);