java.lang.String.getBytes（）和java.nio.charset.CharsetEncoder.encode（）有什么区别？

Question

I was reading through the source code of java.lang.String , specifically getBytes() :

 public byte[] getBytes(Charset charset) {
         if (charset == null) throw new NullPointerException();
            return StringCoding.encode(charset, value, offset, count);
 }

However, I couldn't find the StringCoding.encode() method in the Java API. I'd like to be able to compare it with java.nio.charset.CharsetEncoder.encode() , since that class/method is referenced as an alternative in the String.getBytes() javadoc. How do I find the StringCoding class, and it's source code? And what is the difference between the respective .encode() methods?

Answer 1

The difference is that with a CharsetEncoder you can choose how to fail; this is the CodingErrorAction class.

By default, String 's .getBytes() uses REPLACE . Most uses of CharsetEncoder however will REPORT insead.

You can see an example of CodingErrorAction usage at the end of this page .

One such example of REPORT usage is in java.nio.file. At least on Unix systems, a pathname which you created from a String will be encoded before it is written to disks; if the encoding fails (for instance, you use ö and system charset US-ASCII), the JDK will refuse to create the file and you will be greeted with an (unchecked!) InvalidPathException .

This is unlike File which will create who knows what as a file name, and one more reason to ditch it...