If you have to compile the code for a given processor architecture you would have speed but not portability. With the bytecode, you compile the code (into bytecode) for a common machine that will execute it (the JVM) it is a compromise between speed and portability.
What is the use of bytecode?
Java is a compiled language. The purpose of compiling into bytecode is to allow the code to run on the JVM on any platform. Platform independence is a feature built into java. Furthermore, you don’t have to compile all three class files unless they have inter-dependencies.
Why is bytecode better than machine code?
A major difference between machine code and bytecode is their type. Machine code is a low-level code while bytecode is an intermediate code. It means that machine code can be directly understood by computers while byte code is produced as intermediate code produced after the source code is compiled.
What is the primary advantage of bytecode over object code?
Bytecode creates an extra level of indirection. The advantages of this extra level of indirection are: Platform independence. Can create any number of programming languages (syntax) and have them compile down to the same bytecode.
Who executes the byte code in Java?
JVM executes the byte code generated by compiler and produce output. JVM is the one that makes java platform independent. So to summarise everything: The Java Virtual machine (JVM) is the virtual machine that runs on actual machine (your computer) and executes Java byte code.
Which declarations are required in a Java program?
5) What declarations are required for every Java application? Ans: A class and the main( ) method declarations.
Why Java applications are called WORA language?
JVM is a part of the JRE(Java Runtime Environment). Java applications are called WORA (Write Once Run Anywhere). This means a programmer can develop Java code on one system and can expect it to run on any other Java-enabled system without any adjustment. This is all possible because of JVM.
Why is intermediate code important?
The intermediate code keeps the analysis portion same for all the compilers that’s why it doesn’t need a full compiler for every unique machine. Intermediate code generator receives input from its predecessor phase and semantic analyzer phase. It takes input in the form of an annotated syntax tree.
What is the original name of Java?
The language was initially called Oak after an oak tree that stood outside Gosling’s office. Later the project went by the name Green and was finally renamed Java, from Java coffee, a type of coffee from Indonesia.
How does byte code differ from source code?
The difference between source code and bytecode is that the source code is a collection of computer instructions written using a human-readable programming language while the bytecode is the intermediate code between source code and machine code that is executed by a virtual machine.
Does interpreter generate object code?
To start with, a computer program is usually written in high level language described as a source code. … An interpreter does not generate an intermediary code. Hence, an interpreter is highly efficient in terms of its memory. A compiler always generates an intermediary object code.
What is JIT compiler in Java?
The Just-In-Time (JIT) compiler is a key component of the OpenJ9 VM that improves the performance of Java applications by compiling platform-neutral Java bytecode into native machine code at run time. Without the JIT, the VM has to interpret the bytecodes itself – a process that requires extra CPU and memory.
What is Java encapsulation?
Encapsulation in Java is a mechanism of wrapping the data (variables) and code acting on the data (methods) together as a single unit. In encapsulation, the variables of a class will be hidden from other classes, and can be accessed only through the methods of their current class.
Which produces byte code?
JDK produces bytecode with the compiler (javac), JVM runs it.