In JAVA, the virtual machine is developed in other languages, using C language assembly language. Based on this, it is JAVA itself. The virtual machine only plays a parsing role.
In addition, JAVA is not slower than the C language. When JAVA is said to be slow, it usually refers to JAVA in the 1990s. But now, in a period of excellent JAVA programs and C There is not much difference in program execution efficiency, and now JAVA can be directly compiled into executable files like C language (no virtual machine is needed, at the expense of cross-platform)
I don’t know if you have seen Excellent Programming The second way (use low-level thinking to write high-level code) No, it describes in detail the process of high-level language from writing to compilation and execution. Through the disassembly comparison of target files, it is found that C, C, JAVA, dephi and other languages are of the same quality. There is basically not much difference in the length of the object files under. The running speed of a language is closely related to whether you comply with the compiler rules when writing code. You can read this book when you have time.
The underlying implementation of Java is written in C language. Because it does a lot of encapsulation, it is slower than C language?
JVM is written in C, so a common attack on JVM is buffer overflow.
Written in c language, java6.0 has been open source.
The JVM implementation on the windows platform is written in VC. The JDK you download actually has a src.zip, which is the source code of Java.
It was originally written in C, such as the javac command, etc. The subsequent functions are written by Java itself, such as api. Now most of them are open source. If you are interested, you can check out that project, called openjdk. You can also Provide code, maybe it will be adopted in subsequent versions.
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