Java正则表达式可捕获电子邮件编码的附件字符串

Question

I would like to write a regular expression that catch Encoded Words parts from email MIME message string (eml). for example, this is part of email:

<div dir=3D"ltr"><br clear=3D"all"><div><div dir=3D"ltr"><div style=3D"dire=
ction:rtl">-------------</div><div style=3D"direction:rtl">=D7=91=D7=91=D7=
=A8=D7=9B=D7=94,</div><div style=3D"direction:rtl">=D7=90=D7=91=D7=99=D7=A2=
=D7=93 =D7=9B=D7=94=D7=9F</div></div></div>
</div>

--20cf3003bc2e044e980500f755dc--
--20cf3003bc2e044e9d0500f755de
Content-Type: text/plain; charset=US-ASCII; name="EhudBanay.txt"
Content-Disposition: attachment; filename="EhudBanay.txt"
Content-Transfer-Encoding: base64
X-Attachment-Id: f_hz0z4us30

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RWh1ZF9CYW5haV8tX0FuZV9MaV9fMjAwNF8ucmFyJmg9dkFRRWlEWXFu
--20cf3003bc2e044e9d0500f755de--

i would like to catch only this part:

aHR0cHM6Ly93d3cuZmFjZWJvb2suY29tL2wucGhwP3U9aHR0cHMlM0ElMkYlMkZ3d3cucmFwaWRz
aGFyZS5jb20lMkZmaWxlcyUyRjM4NzAxNTA2MDclMkZFaHVkX0JhbmFpXy1fVGlwX1RpcGFfXzE5
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dHRwcyUzQSUyRiUyRnd3dy5yYXBpZHNoYXJlLmNvbSUyRmZpbGVzJTJGMzk5MzMyNjg1MSUyRkVo
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RWh1ZF9CYW5haV8tX0FuZV9MaV9fMjAwNF8ucmFyJmg9dkFRRWlEWXFu

I wrote the folowing regular expression: (?<=\\r\\n\\r\\n)(.+\\r\\n)+(?=--) which provide the results i want. i assume that: * the regular expression should return all the occurrences of such parts. multiple * before the wanted part there is always an empty line. * the wanted part is always followed by a line start with "--" (there might be a seperation line between them).

The problem with this solution is that i get Exception in thread "main" java.lang.StackOverflowError when the input string is long, what makes me think of the regular expression efficiency. I would like to make the regular expression more precise. we can make use of the fact that somewhere before the empty line that comes before the wanted part, there is always a line starting with "Content-Transfer-Encoding:". Can someone please help?

Answer 1

您可以尝试增加堆栈大小：-Xss2048k