JVM (Java Virtual Machine) is an abstract machine. -

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i java beginner. read line " jvm (java virtual machine) abstract machine." can please me understand term abstract machine. abstract machine.

an abstract machine machine not have physical existence.

abstractness

  • a bicycle has physical existence. can touch it. not abstract.

  • a computer chip has physical existence. can touch it. not abstract.

  • a jvm executing program ... , has no physical existence. cannot touch it. abstract.

machine-ness:

  • a bicycle machine transporting people.

  • a computer chip machine executing programs ... coded in instruction set of chip; e.g. intel x86 machine code.

  • a jvm machine executing programs ... coded in instruction set of jvms; i.e. java bytecodes.


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