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"Illegal character 0x0 in state=METHOD" when trying to connect to localhost

User_ATT1LJun 9 2022

Hello, People!

I have the latest version of JMC, but when I try to connect to an application running on localhost, I get the following error messages:
[qtp1935621678-137] WARN org.eclipse.jetty.http.HttpParser - Illegal character 0x0 in state=METHOD for buffer HeapByteBuffer@380f38f6[p=5,l=7,c=8192,r=2]={JRMI\x00<<<\x02K>>>\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00...\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00}
[qtp1935621678-137] WARN org.eclipse.jetty.http.HttpParser - bad HTTP parsed: 400 Illegal character 0x0 for HttpChannelOverHttp@2f102959{r=0,c=false,a=IDLE,uri=null}
[qtp1935621678-134] WARN org.eclipse.jetty.http.HttpParser - Illegal character 0x16 in state=START for buffer HeapByteBuffer@45b26de8[p=1,l=452,c=8192,r=451]={\x16<<<\x03\x03\x01\xBf\x01\x00\x01\xBb\x03\x03]*s\xC4?J\xFe...E"\xCf\x94\xD7v\xFaQ\x19(&\r\xAe\n\xBf>>>\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00...\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00}
[qtp1935621678-134] WARN org.eclipse.jetty.http.HttpParser - bad HTTP parsed: 400 Illegal character 0x16 for HttpChannelOverHttp@4b758b2e{r=0,c=false,a=IDLE,uri=null}
Can somebody please help?

Comments

843811
Such optimization are done by JIT compiler (not by javac).
C++ have just the same problems, exceptions make CFG analisis more difficult but not impossible.
PS You can read JLS about volatile variables there some additional restrictions on them.
843811
zhmur is right, this makes optimization harder not impossible.

There are sicentific papers aimed at making more analysis/optimization in the presence of many try/catch blocks. For instance, JIT can reorder statements, and then put compensation code into the catch body, recovering program state back if an exception was thrown.

General principle is simple: exceptions are rare. So JIT optimizes the "normal" control flow by the cost of more complex catch body.

You may also look/post to the comp.compilers newsgroup regarding compilers and optimization techniques

Denis

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Added on Jun 9 2022
#java-mission-control
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