Which component runs Java programs at runtime?

Which component runs Java programs at runtime?

• A. JIT Compiler
• B. JRE
• C. JVM
• D. Java Parser

Answer: (B)

When you run a Java program, the code that actually executes the bytecode is the Java Virtual Machine (JVM). The JVM can interpret bytecode or compile frequently run sections to native code at runtime (via the JIT compiler) to improve performance. The Java Runtime Environment (JRE) provides the runtime setup—the JVM plus the standard libraries—so programs can run, but the real execution happens inside the JVM itself. The JIT is not a separate runner; it’s a performance feature inside the JVM. A Java Parser, on the other hand, is used for reading and analyzing code, not for executing it.

When you run a Java program, the code that actually executes the bytecode is the Java Virtual Machine (JVM). The JVM can interpret bytecode or compile frequently run sections to native code at runtime (via the JIT compiler) to improve performance. The Java Runtime Environment (JRE) provides the runtime setup—the JVM plus the standard libraries—so programs can run, but the real execution happens inside the JVM itself. The JIT is not a separate runner; it’s a performance feature inside the JVM. A Java Parser, on the other hand, is used for reading and analyzing code, not for executing it.