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 fpcf
    Definition Classes
    ai
  • package analyses
    Definition Classes
    fpcf
  • DomainBasedFPCFAnalysisScheduler
  • EagerL0BaseAIAnalysis
  • EagerLBFieldValuesAnalysis
  • EagerLBMethodReturnValuesAnalysis
  • FieldValuesAnalysis
  • L0BaseAIResultAnalysis
  • L0BaseAIResultAnalysisScheduler
  • LBFieldValuesAnalysis
  • LBMethodReturnValuesAnalysis
  • LazyL0BaseAIAnalysis
c

org.opalj.ai.fpcf.analyses

LBFieldValuesAnalysis

class LBFieldValuesAnalysis extends FPCFAnalysis

Computes for each private field an approximation of the type of values stored in the field.

Basically, we perform an abstract interpretation of all methods that assign a value to the field to compute the type of the values stored in the field.

This analysis is deliberately optimized for performance and, given that we don't have precise call-graph information and also don't track the origin of values, we can't track the overall nullness property of the values stored in a field. E.g., even if we always see that a field is only written in the constructor we still don't know if that happens w.r.t. this or some other instance and whether the field was actually read before that!

Self Type
LBFieldValuesAnalysis
Source
LBFieldValuesAnalysis.scala
Note

This is a very, very shallow analysis and improvements w.r.t. the precision are easily imaginable.

,

ADDITIONALLY, WE HAVE TO IGNORE THOSE FIELDS WHICH SEEMS TO BE ALWAYS NULL BECAUSE THESE FIELDS ARE OFTEN INITIALZED - AT RUNTIME - BY SOME CODE OUTSIDE THE SCOPE OF "PURE" JAVA BASED ANALYSES. E.G., WE IGNORE THE FOLLOWING FIELDS FROM JAVA 8:

  • [BY NAME] java.util.concurrent.FutureTask{ runner:null // Originaltype: java.lang.Thread }
  • [BY NAME] java.nio.channels.SelectionKey{ attachment:null // Originaltype: java.lang.Object }
  • [BY SETTER] java.lang.System{ err:null // Originaltype: java.io.PrintStream }
  • [BY SETTER] java.lang.System{ in:null // Originaltype: java.io.InputStream }
  • [BY SETTER] java.lang.System{ out:null // Originaltype: java.io.PrintStream }
  • [BY CONSTRUCTOR] java.net.InterfaceAddress{ address:null // Originaltype: java.net.InetAddress } [UPDATE BY NATIVE CODE...] sun.nio.ch.sctp.ResultContainer{ value:null // Originaltype: java.lang.Object } THE FOLLOWING FIELDS ARE "REALLY" NULL in JAVA 8 (1.8.0 - 1.8.0_25):
  • [OK] java.util.TimeZone{ NO_TIMEZONE:null // Originaltype: java.util.TimeZone }
  • [OK - DEPRECATED] java.security.SecureRandom{ digest:null // Originaltype: java.security.MessageDigest } The reason/purpose is not 100% clear:
  • [OK] javax.swing.JList.AccessibleJList.AccessibleJListChild{ accessibleContext:null }
  • [OK] javax.swing.JList.AccessibleJList.AccessibleJListChild{ component:null }
  • [OK] com.sun.corba.se.impl.io.IIOPInputStream{ abortIOException:null }
  • [OK] com.sun.corba.se.impl.orb.ORBImpl{ codeBaseIOR:null }
  • [OK - ACCIDENTIALLY CREATED?] com.sun.org.apache.xpath.internal.jaxp.XPathImpl{ d:null }
  • [OK - LEGACY CODE?] javax.swing.JPopupMenu{ margin:null }
  • [OK - LEGACY CODE?] sun.audio.AudioDevice{ mixer:null }
  • [OK - RESERVED FOR FUTURE USAGE] com.sun.corba.se.impl.corba.ServerRequestImpl{ _ctx:null }
  • [OK - LEGACY CODE?] com.sun.java.swing.plaf.motif.MotifPopupMenuUI{ border:null }
  • [OK - LEGACY CODE?] com.sun.media.sound.SoftSynthesizer{ testline:null }
  • [OK - LEGACY CODE?] com.sun.org.apache.xerces.internal.impl.xs.XMLSchemaLoader{ fSymbolTable:null }
  • [OK - LEGACY CODE] com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl{ _piParams:null }
  • [OK - RESERVED FOR FUTURE USAGE?] com.sun.org.apache.xml.internal.dtm.ref.DTMDefaultBase{ m_namespaceLists:null }
  • [OK - LEGACY CODE?] sun.awt.motif.MFontConfiguration{ fontConfig:null }
  • [OK - LEGACY CODE?] sun.print.PSStreamPrintJob{ reader:null }
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Inherited
  1. LBFieldValuesAnalysis
  2. FPCFAnalysis
  3. ProjectBasedAnalysis
  4. AnyRef
  5. Any
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  2. Protected

Type Members

  1. class FieldValuesAnalysisDomain extends CorrelationalDomain with TheProject with TheCode with DefaultSpecialDomainValuesBinding with ThrowAllPotentialExceptionsConfiguration with DefaultIntegerValues with DefaultTypeLevelLongValues with DefaultTypeLevelFloatValues with DefaultTypeLevelDoubleValues with TypeLevelPrimitiveValuesConversions with TypeLevelLongValuesShiftOperators with TypeLevelFieldAccessInstructions with TypeLevelInvokeInstructions with TypeLevelDynamicLoads with DefaultReferenceValuesBinding with DefaultHandlingOfMethodResults with IgnoreSynchronization with RefinedTypeLevelFieldAccessInstructions

    The domain used for analyzing the values stored in a field.

    The domain used for analyzing the values stored in a field.

    One instance of this domain is used to analyze all methods of the respective class. Only after the analysis of all methods, the information returned by FieldValuesAnalysisDomain#fieldInformation is guaranteed to be correct.

Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##: Int
    Definition Classes
    AnyRef → Any
  3. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  4. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  5. final def ch: ClassHierarchy
    Definition Classes
    ProjectBasedAnalysis
  6. implicit final def classHierarchy: ClassHierarchy
    Definition Classes
    ProjectBasedAnalysis
  7. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.CloneNotSupportedException]) @native() @IntrinsicCandidate()
  8. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  9. def equals(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef → Any
  10. final val fieldAccessInformation: FieldAccessInformation
  11. final def getClass(): Class[_ <: AnyRef]
    Definition Classes
    AnyRef → Any
    Annotations
    @native() @IntrinsicCandidate()
  12. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @native() @IntrinsicCandidate()
  13. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  14. implicit final def logContext: LogContext
    Definition Classes
    ProjectBasedAnalysis
  15. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  16. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native() @IntrinsicCandidate()
  17. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native() @IntrinsicCandidate()
  18. implicit final def p: SomeProject
    Definition Classes
    ProjectBasedAnalysis
  19. val project: SomeProject
  20. implicit final val propertyStore: PropertyStore
    Definition Classes
    FPCFAnalysis
  21. final def ps: PropertyStore
    Definition Classes
    FPCFAnalysis
  22. def relevantFieldsIterable(classFile: ClassFile): Iterable[Field]

    Computes the set of the fields which are potentially refinable w.r.t.

    Computes the set of the fields which are potentially refinable w.r.t. type information.

  23. final def synchronized[T0](arg0: => T0): T0
    Definition Classes
    AnyRef
  24. def toString(): String
    Definition Classes
    AnyRef → Any
  25. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  26. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  27. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])

Deprecated Value Members

  1. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.Throwable]) @Deprecated
    Deprecated

Inherited from FPCFAnalysis

Inherited from ProjectBasedAnalysis

Inherited from AnyRef

Inherited from Any

Ungrouped