What is JVM? Why is Java called the "Platform Independent Programming Language"?
Câu trả lời What is JVM? Why is Java called the "Platform Independent Programming Language"?
What is JVM?
The Java Virtual Machine (JVM) is a core component of the Java programming environment. It is an abstract computing machine that enables a computer to run Java programs, as well as programs written in other languages that are compiled to Java bytecode[10]. The JVM is responsible for interpreting bytecode and executing the Java program. The JVM acts as a "virtual" processor that executes Java bytecode, which is a set of instructions that the JVM understands. This bytecode is generated from Java source code through a compiler.
The JVM is designed to be platform-independent in its specification but platform-dependent in its implementation. That is, the way JVM operates is standardized through a specification, but the actual implementations of this specification are tailored to specific operating systems. This means that while Java programs are written to be platform-independent, the JVM has to be specifically implemented for each platform[9][10].
Why is Java called the "Platform Independent Programming Language"?
Java is termed a "Platform Independent Programming Language" primarily because of its ability to run the same program on multiple operating systems without modification. This capability stems from the use of Java bytecode and the JVM.
Bytecode: When Java programs are compiled, they are not compiled into platform-specific machine code but into a platform-neutral bytecode. This bytecode is a low-level set of instructions that is not specific to any one processor or operating system[1][2][7].
Java Virtual Machine (JVM): This bytecode does not run directly on any hardware, but needs a JVM to execute. Each operating system has its own JVM that interprets or compiles this bytecode into native machine code at runtime. Thus, the same Java program (in the form of bytecode) can run on different operating systems, each with its own JVM implementation, without needing to be rewritten or recompiled for each one[1][2].
Write Once, Run Anywhere (WORA): This principle is at the heart of Java's architecture. It allows develop...
