javap

Javap is a command line tool that comes with the Java Development Kit (JDK) and is used for viewing the bytecode of compiled Java classes. It allows developers to analyze and understand the internal structure of Java classes.

When executed with the "javap" command followed by the name of a class, Javap displays various information about that class. This includes the package, the access modifiers of the class and its members, the superclass and implemented interfaces, and more.

Javap also provides details about the fields and methods within a class, including their names, data types, and access modifiers. It shows the bytecode instructions for each method, allowing developers to understand the low-level operations performed by the JVM.

Additionally, Javap can decompile Java classes and display the corresponding source code. This can be useful for exploring how a given class is implemented, especially when the original source code is not available.

Javap has several options that can be used to customize its output. For example, the "-c" option displays the bytecode instructions of each method, the "-s" option prints the internal signatures of each class member, and the "-verbose" option provides even more detailed information.

This command line tool is often used by Java developers for debugging, performance analysis, and reverse engineering. It helps them gain insights into the structure and behavior of Java classes, facilitating efficient code understanding and troubleshooting.

Javap can also be integrated into build scripts and IDEs, making it possible to automatically inspect and analyze Java classes as part of the development process.

Overall, Javap is a powerful and versatile tool for examining and understanding compiled Java code, providing developers with valuable information about the internals of classes and their bytecode instructions.