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Java: Fundamentals

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وابستگی کمپایلرها به پلتفرم ها

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ایده ای برای استقالل از پلتفرم

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JVMمعرفی

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فرایند اجرای کد جاوا

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فرایند اجرای کد جاوا )ادامه(

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فرایند اجرای کد جاوا )ادامه(

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JVM و JRE،JDK Java Development Kit (JDK): This includes

ALL the basic Java framework packages, a compiler (javac), JRE, a JVM, debugger etc.

in short all you need to develop, debug, compile and run our Java program.

Java Runtime Environment (JRE): This is a subset of the JDK. It does not include a

debugger, compiler, and framework classes. This includes the bare minimum that a

computer needs in order to run a .class file.

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Java Virtual Machine (JVM): JVM is a part of JRE. The .class file is passed

over to JVM which then runs the program. The JRE ensures that the code does not

violate any of the security restrictions. Remember that the byte-code (.class file) is

not directly run on the host machine; it needs to be converted to the host machine's

language. This conversion is done by the JVM. While converting the JVM ensures the

security and may also optimize the code.

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