Javassist

Last updated
Javassist
Developer(s) Shigeru Chiba (programmer)
Stable release
3.25.0-GA / April 16, 2019 (2019-04-16)
Repository
Written in Java
Operating system Cross-platform
Type Bytecode Engineering Library
License dual license of the MPL and LGPL.
Website www.javassist.org

Javassist (Java programming assistant) is a Java library providing a means to manipulate the Java bytecode of an application. [1] In this sense Javassist provides the support for structural reflection, i.e. the ability to change the implementation of a class at run time.

Contents

Bytecode manipulation is performed at load-time through a provided class loader.

Javassist enables Java programs to define a new class at runtime and to modify a class file when the JVM loads it. Unlike other similar bytecode editors, Javassist provides two levels of API: source level and bytecode level. Using the source-level API, programmers can edit a class file without knowledge of the specifications of the Java bytecode; the whole API is designed with only the vocabulary of the Java language. Programmers can even specify inserted bytecode in the form of Java source text; Javassist compiles it on the fly. On the other hand, the bytecode-level API allows the users to directly edit a class file as other editors.

Uses

Javassist can be used for the following:

See also

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References

  1. "Javassist". JBoss Community.

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