Packages

Definition Classes: root

Definition Classes: root

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 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.

Definition Classes: opalj

package constraints

Defines helper values and methods related to modeling constraints.

Definition Classes: opalj

package control

Defines common control abstractions.

Definition Classes: opalj

package graphs

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:

graphs based on explicitly connected nodes (org.opalj.graphs.Node),
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.

Definition Classes: opalj
Note: The implementations of the methods rely on Java NIO(2).

package log

Definition Classes: opalj

package util

Utility methods.

Definition Classes: opalj

org.opalj

log

package log

Ordering

Alphabetic

Visibility

Public
Protected

Type Members

case class BasicLogMessage(level: Level = Info, message: String) extends LogMessage with Product with Serializable
Default implementation of a log message.
class ConsoleOPALLogger extends OPALLogger
The console logger is a very basic logger that ignores the context.
case class ExceptionLogMessage(level: Level = Info, category: Option[String] = None, baseMessage: String, t: Throwable) extends LogMessage with Product with Serializable
sealed abstract class Level extends AnyRef
Common super trait of all log levels.
trait LogContext extends AnyRef
A log context associates log messages with a specific context and logger.
A log context associates log messages with a specific context and logger. Using a log context facilitates the suppression of recurring message in a specific context and also makes it possible to direct messages to different targets. Before using a LogContext it has to be registered with the OPALLogger$.
OPAL uses two primary log contexts:
1. The GlobalLogContext$ which should be used for general log messages related to OPAL, such as the number of threads used for computations.
2. The log context associated with org.opalj.br.analyses.Projects to log project related information (e.g., such as project related results or configuration issues.)
Note
The registration of the LogContext with the OPALLogger does not prevent the garbage collection of the LogContext unless a logged message explicitly references its log context. This is – however – discouraged! If no message explicitly reference the log context it is then possible to unregister the log context in the finalize method that references the context.
trait LogMessage extends AnyRef
Description of a log message.
Description of a log message.
Implementation Guidelines
A LogMessage should never contain a direct reference to a LogContext object.
trait OPALLogger extends AnyRef
Facilitates the logging of messages that are relevant for the end user.
Facilitates the logging of messages that are relevant for the end user.
Usage
To use OPAL's logging facility use the companion object (OPALLogger$).
Note
The OPALLogger framework is not intended to be used by developers to help debug analysis; it is intended to be used to inform (end)-users about the analysis progress.
case class StandardLogContext extends LogContext with Product with Serializable
case class StandardLogMessage(level: Level = Info, category: Option[String] = None, message: String) extends LogMessage with Product with Serializable
Default implementation of a log message.

Value Members

object DevNullLogger extends OPALLogger
An instance of OPALLogger that does not perform _any logging_ .
An instance of OPALLogger that does not perform _any logging_ .
In general, it is HIGHLY recommended to use the ConsoleOPALLogger and to the set the minimium log level to Error.
case object Error extends Level with Product with Serializable
Factory for error level log messages.
Factory for error level log messages.
See also
OPALLogger$ for usage instructions.
case object Fatal extends Level with Product with Serializable
case object GlobalLogContext extends LogContext with Product with Serializable
The global log context which should be used to log global messages.
The global log context which should be used to log global messages.
This context is automatically registered with the OPALLogger framework and uses, by default, a ConsoleOPALLogger.
case object Info extends Level with Product with Serializable
Factory for info level log messages.
Factory for info level log messages.
See also
OPALLogger$ for usage instructions.
object LogMessage

object OPALLogger extends OPALLogger

OPAL's logging facility.

Usage

Basic

E.g., using the global context and the convenience methods.

implicit val logContext : LogContext = org.opalj.log.GlobalContext
OPALLogger.info("project", "the project is garbage collected")

OPALLogger.info("project", "the project is garbage collected")(org.opalj.log.GlobalContext)

Advanced

Logging a message only once.

implicit val logContext : LogContext = org.opalj.log.GlobalContext
OPALLogger.logOnce(Warn("project configuration", "the method cannot be resolved"))

Initialization

If the GlobalLogContext should not use the default ConsoleOPALLogger then the logger can be changed using updateLogger.

Thread Safety

Thread safe.

case object Warn extends Level with Product with Serializable
Factory for warn level log messages.
Factory for warn level log messages.
See also
OPALLogger$ for usage instructions.

Packages

General Design Decisions

Thread Safety

No null Values

No Typecasts for Collections

Assertions

Design Goals

Integration With Scala's Collection Library

Status

log

package log

Type Members

Implementation Guidelines

Usage

Value Members

Usage

Basic

Advanced

Initialization

Thread Safety

Ungrouped

No `null` Values

log