Geek asks and answers

What is the internal identification of the Java method?

As you know, in Java, the method name is not enough to distinguish between different methods.

I think (it may be wrong) to distinguish a method, it needs the following information:

(className, methodName, methodParameters)

Further,

  • How to determine the method more efficiently within the country?
  • I heard about the "id method". Does this mean that there is a mapping between the above triple and the integer, so the JVM uses only the method identifier after parsing?
  • If so, is it in the symbol table?

Thank!

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4 answers

This is a CONSTANT_NameAndType_info structure that points to a method handle.

This is mainly the name of the method, parameter types and (somewhat surprisingly) the return type.

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