Packages

•  package root

  Definition Classes

  root

•  package org

  Definition Classes

  root

•  package opalj

  OPAL is a Scala-based framework for the static analysis, manipulation and creation of Java bytecode.

  OPAL is a Scala-based framework for the static analysis, manipulation and creation of Java bytecode. OPAL is designed with performance, scalability and adaptability in mind.

  Its main components are:

  • a library (Common) which provides generally useful data-structures and algorithms for static analyses.
  • a framework for implementing lattice based static analyses (Static Analysis Infrastructure)
  • a framework for parsing Java bytecode (Bytecode Infrastructure) that can be used to create arbitrary representations.
  • a library to create a one-to-one in-memory representation of Java bytecode (Bytecode Disassembler).
  • a library to create a representation of Java bytecode that facilitates writing simple static analyses (Bytecode Representation - org.opalj.br).
  • a scalable, easily customizable framework for the abstract interpretation of Java bytecode (Abstract Interpretation Framework - org.opalj.ai).
  • a library to extract dependencies between code elements and to facilitate checking architecture definitions.
  • a library for the lightweight manipulation and creation of Java bytecode (Bytecode Assembler).

  General Design Decisions

  Thread Safety

  Unless explicitly noted, OPAL is thread safe. I.e., the classes defined by OPAL can be considered to be thread safe unless otherwise stated. (For example, it is possible to read and process class files concurrently without explicit synchronization on the client side.)

  No null Values

  Unless explicitly noted, OPAL does not null values I.e., fields that are accessible will never contain null values and methods will never return null. If a method accepts null as a value for a parameter or returns a null value it is always explicitly documented. In general, the behavior of methods that are passed null values is undefined unless explicitly documented.

  No Typecasts for Collections

  For efficiency reasons, OPAL sometimes uses mutable data-structures internally. After construction time, these data-structures are generally represented using their generic interfaces (e.g., scala.collection.{Set,Map}). However, a downcast (e.g., to add/remove elements) is always forbidden as it would effectively prevent thread-safety.

  Assertions

  OPAL makes heavy use of Scala's Assertion Facility to facilitate writing correct code. Hence, for production builds (after thorough testing(!)) it is highly recommend to build OPAL again using -Xdisable-assertions.

  Definition Classes

  org

•  package ai

  Implementation of an abstract interpretation (ai) framework – also referred to as OPAL.

  Implementation of an abstract interpretation (ai) framework – also referred to as OPAL.

  Please note that OPAL/the abstract interpreter just refers to the classes and traits defined in this package (ai). The classes and traits defined in the sub-packages (in particular in domain) are not considered to be part of the core of OPAL/the abstract interpreter.

  Definition Classes

  opalj

  Note

  This framework assumes that the analyzed bytecode is valid; i.e., the JVM's bytecode verifier would be able to verify the code. Furthermore, load-time errors (e.g., LinkageErrors) are – by default – completely ignored to facilitate the analysis of parts of a project. In general, if the presented bytecode is not valid, the result is undefined (i.e., OPAL may report meaningless results, crash or run indefinitely).

  See also

  org.opalj.ai.AI - Implements the abstract interpreter that processes a methods code and uses an analysis-specific domain to perform the abstract computations.

  org.opalj.ai.Domain - The core interface between the abstract interpretation framework and the abstract domain that is responsible for performing the abstract computations.

•  package av

  Definition Classes

  opalj

•  package ba

  Implementation of an eDSL for creating Java bytecode.

  Implementation of an eDSL for creating Java bytecode. The eDSL is designed to facilitate the creation of correct class files; i.e., whenever possible it tries to fill wholes. For example, when an interface is specified the library automatically ensures that the super class type is (initially) set to java.lang.Object as required by the JVM specification.

  This package in particular provides functionality to convert org.opalj.br classes to org.opalj.da classes.

  Definition Classes

  opalj

•  package bc

  Definition Classes

  opalj

• Assembler
• ClassFileElement
• MethodFilter
•  package bi

  Implementation of a library for parsing Java bytecode and creating arbitrary representations.

  Implementation of a library for parsing Java bytecode and creating arbitrary representations.

  OPAL's primary representation of Java byte code is the org.opalj.br representation which is defined in the respective package. A second representation that represents bytecode one-by-one is found in the org.opalj.da package.

  This Package

  Common constants and type definitions used across OPAL.

  Definition Classes

  opalj

•  package br

  In this representation of Java bytecode references to a Java class file's constant pool and to attributes are replaced by direct references to the corresponding constant pool entries.

  In this representation of Java bytecode references to a Java class file's constant pool and to attributes are replaced by direct references to the corresponding constant pool entries. This facilitates developing analyses and fosters comprehension.

  Based on the fact that indirect references to constant pool entries are resolved and replaced by direct references this representation is called the resolved representation.

  This representation of Java bytecode is considered as OPAL's standard representation for writing Scala based analyses. This representation is engineered such that it facilitates writing analyses that use pattern matching.

  Definition Classes

  opalj

•  package bytecode

  Defines functionality commonly useful when processing Java bytecode.

  Defines functionality commonly useful when processing Java bytecode.

  Definition Classes

  opalj

•  package collection

  OPAL's collection library is primarily designed with high performance in mind.

  Design Goals

  OPAL's collection library is primarily designed with high performance in mind. I.e., all methods provided by the collection library are reasonably optimized. However, providing a very large number of methods is a non-goal. Overall, OPAL's collection library provides:

  • collection classes that are manually specialized for primitive data-types.
  • collection classes that are optimized for particularly small collections of values.
  • collection classes that target special use cases such as using a collection as a workset/worklist.
  • collection classes that offer special methods that minimize the number of steps when compared to general purpose methods.

  Integration With Scala's Collection Library

  Hence, OPAL's collection library complements Scala's default collection library and is not intended to replace it. Integration with Scala's collection library is primarily provided by means of iterators (OPAL's Iterators inherit from Scala's Iterators). Furthermore the companion object of each of OPAL's collection classes generally provides factory methods that facilitate the conversion from Scala collection classes to OPAL collection classes.

  Status

  The collection library is growing. Nevertheless, the existing classes are production ready.

  Definition Classes

  opalj

•  package concurrent

  Common constants, factory methods and objects used throughout OPAL when performing concurrent computations.

  Common constants, factory methods and objects used throughout OPAL when performing concurrent computations.

  Definition Classes

  opalj

•  package constraints

  Defines helper values and methods related to modeling constraints.

  Defines helper values and methods related to modeling constraints.

  Definition Classes

  opalj

•  package control

  Defines common control abstractions.

  Defines common control abstractions.

  Definition Classes

  opalj

•  package da

  Defines convenience methods related to representing certain class file elements.

  Defines convenience methods related to representing certain class file elements.

  Definition Classes

  opalj

•  package de

  Functionality to extract dependencies between class files.

  Functionality to extract dependencies between class files.

  Definition Classes

  opalj

•  package fpcf

  The fixpoint computations framework (fpcf) is a general framework to perform fixpoint computations of properties ordered by a lattice.

  The fixpoint computations framework (fpcf) is a general framework to perform fixpoint computations of properties ordered by a lattice. The framework in particular supports the development of static analyses.

  In this case, the fixpoint computations/static analyses are generally operating on the code and need to be executed until the computations have reached their (implicit) fixpoint. The fixpoint framework explicitly supports resolving cyclic dependencies/computations. A prime use case of the fixpoint framework are all those analyses that may interact with the results of other analyses.

  For example, an analysis that analyzes all field write accesses to determine if we can refine a field's type (for the purpose of the analysis) can (reuse) the information about the return types of methods, which however may depend on the refined field types.

  The framework is generic enough to facilitate the implementation of anytime algorithms.

  Definition Classes

  opalj

  Note

  This framework assumes that all data-structures (e.g., dependee lists and properties) that are passed to the framework are effectively immutable! (Effectively immutable means that a data structure is never updated after it was passed to the framework.)

  ,

  The dependency relation is as follows: “A depends on B” === “A is the depender, B is the dependee”. === “B is depended on by A”

  ,

  The very core of the framework is described in: Lattice Based Modularization of Static Analyses

•  package graphs

  This package defines graph algorithms as well as factory methods to describe and compute graphs and trees.

  This package defines graph algorithms as well as factory methods to describe and compute graphs and trees.

  This package supports the following types of graphs:

  1. graphs based on explicitly connected nodes (org.opalj.graphs.Node),
  2. graphs where the relationship between the nodes are encoded externally (org.opalj.graphs.Graph).

  Definition Classes

  opalj

•  package io

  Various io-related helper methods and classes.

  Various io-related helper methods and classes.

  Definition Classes

  opalj

  Note

  The implementations of the methods rely on Java NIO(2).

•  package issues

  Defines implicit conversions to wrap some types of analyses such that they generate results of type org.opalj.br.analyses.ReportableAnalysisResult.

  Defines implicit conversions to wrap some types of analyses such that they generate results of type org.opalj.br.analyses.ReportableAnalysisResult.

  Definition Classes

  opalj

•  package log

  Definition Classes

  opalj

•  package tac

  Common definitions related to the definition and processing of three address code.

  Common definitions related to the definition and processing of three address code.

  Definition Classes

  opalj

•  package util

  Utility methods.

  Utility methods.

  Definition Classes

  opalj

•  package value

  Provides a general query interface for querying a value's properties.

  Provides a general query interface for querying a value's properties.

  Definition Classes

  opalj

org.opalj

bc 