"Read/write" method of "Input/OutputStream" are not synchronized. but "ByteArrayInput/OutputStream" are synchronized methods. Old version opack call "read/write

"Read/write" method of "Input/OutputStream" are not synchronized. but "ByteArrayInput/OutputStream" are synchronized methods. Old version opack call "read/write" method frequently, but only call from single thread. (not allow multiple thread use to one context) before JVM15, synchronized "read/write" method of "ByteArrayInput/OutputStream" was cheap, when single thread going through. (use biased locking) "JEP 374" has a performance penalty for single threads going through syncrozied blocks.