Output stream over a StringBuilder

Question

I think this has been answered but I can't seem to find it.

I have an instance method which writes some contents to an output stream

writeTo(OutputStream){
     //class specific logic
}

I want it to get these contents into a StringBuilder. I can do this via a temporary file but that does not seem right. I want to do something like:

Stringbuilder sb = /* */;
OutputStream os = outForStringBuilder(sb);//not sure how to do this
instance.writeTo(os); //This should write the contents to Stringbuilder

You want to write the String in the `StringBuilder` to an `OutputStream`? — Sotirios Delimanolis, Aug 30 '13 at 03:22
@SotiriosDelimanolis The other way around. Updated the question to make it clearer — rocketboy, Aug 30 '13 at 03:31

Tom · Answer 1 · 2015-11-24T05:24:56.327

13

Use a ByteArrayOutputStream and then call toString(charSet) - no need for a StringBuilder.

edited Nov 24 '15 at 05:24

answered Aug 30 '13 at 03:23

Tom

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score 2 · Accepted Answer · answered Aug 30 '13 at 03:30

So you are wanting output written to the stream to go to a StringBuffer instead. I am assuming you are doing this because an OutputStream is required somewhere else. You could use ByteArrayOutputStream, but if you want to preserve the StringBuffer behavior, you might simply wrap a StringBuffer in a subclass of OutputStream like the code here:

http://geronimo.apache.org/maven/specs/geronimo-javamail_1.4_spec/1.6/apidocs/src-html/org/apache/geronimo/mail/util/StringBufferOutputStream.html#line.31

Output stream over a StringBuilder

2 Answers2