ChangeLog

LATEST

  * Improved diamond type inference.
  * More robust string concatenation code generation, handling
  left-associative addition trees.
  * Remove SuperClass component of PrimitiveType.
  * More explicit subtyping rules for primitive types.
  * Marked TypeDecl.instanceOf as deprecated.
  * Replaced the instanceOf by subtype and removed redundant subtype
  equations.
  * Removed the EmptyType AST class.
  * Refactored scanner specifications.

2018-12-12 Version 8.1.2

  * The Options class has been moved from the aspect file
  java4/frontend/Options.jadd to the plain Java file
  src/frontend/org/extendj/ast/Options.java.
  * Removed a JastAdd rewrite that normalized the TypeBound list of
  TypeVariable nodes.  The TypeBound list child of TypeVariable was renamed to
  Bound, and attributes emulating the old TypeBound interface were added.  The
  new attributes getNumTypeBound(), getTypeBound(int), and getTypeBoundList()
  are used to work with the normalized list of type variable bounds. If the
  actual declared bounds are needed, use getNumBound(), getBound(int), and
  getBoundList().
  * Rewrote TypeVariable.firstBound() - it no longer returns the least upper
  bound of the type variable. TypeVariable.firstBound() now returns the first
  type bound or the Object type access if the type variable is unbounded.  Use
  TypeVariable.lubType() instead to get the least upper bound.
  * Removed attribute TypeVariable.lowerBound() because the name was
  misleading and it was only used in one place.
  * Deleted SimpleSet.fullSet as it was unused.
  * Removed ID token in ThisAccess and SuperAccess.
  * Changed Expr.mayAccess(Variable) to a synthesized attribute (was
    inter-type declared method).
  * Removed method TypeDecl.mayAccess(Expr, Variable).
  * Added attribute TypeDecl.mayAccess(TypeDecl, Variable).
  * Added TypeDecl.keepAccessibleFields(TypeDecl, SimpleSet<Variable>) as a
    helper method for field access control.
  * Added attribute MethodAccess.hasUnknownArg() to check if any of the
    arguments to a method call has unknown type.

2018-01-25  Version 8.1.1

  * Unified diamond type inference with method type inference.
    A synthetic method access is now used by DiamondAccess to infer type
    arguments. This means that much more of the method type inference
    implementation can be reused directly by the diamond implementation.
  * Removed attributes:
      - DiamondAccess.mostSpecific(_, _)
      - DiamondAccess.potentiallyApplicable(_)
      - DiamondAccess.applicableBySubtyping(_, _)
      - DiamondAccess.applicableByMethodInvocationConversion(_, _)
      - DiamondAccess.applicableByVariableArity(_, _)
  * Changed the argument type of MethodAccess.maxSpecific() from Collection to Iterable.
  * Changed the Argument type of MethodAccess.potentiallyApplicable() from
    Collection to Iterable.
  * Changed TypeDecl.bridgeMethods() from collection attribute to synthesized
    attribute.
  * Removed the attribute TypeDecl.localBridgeMethods() (renamed to
    "bridgeMethods").
  * The attribute SwichStmt.enumIndices() has been moved to TypeDecl.
    This attribute is used to generate implicit enum switch maps.
  * Elements in the SimpleSet datastructure is are now ordered by insertion
    order. This makes the element order deterministic.
  * Added NTA TryWithResources.closeAccess() to represent the implicit
    resource closing method access in a TWR statement.
  * Removed TryWithResources.lookupClose().
    Use TryWithResources.closeAccess().decl() instead.
  * Added attribute TypeDecl.methods(), which computes all visible method
    declarations for a type (includes inherited methods).
  * Removed TypeDecl.methodsIterator().
    Use TypeDecl.methods().iterator() instead.
  * Added attribute TypeDecl.interfacesMethods(), which computes all methods
    inherited from superinterfaces (transitive).
  * Removed TypeDecl.interfacesMethodsIterator().
    Use TypeDecl.interfacesMethods().iterator() instead.
  * Added attribute TypeDecl.localMethods(), which computes all local method
    declarations for a type.
  * Removed TypeDecl.localMethodsIterator().
    Use TypeDecl.localMethods().iterator() instead.
  * Removed TypeDecl.interfacesIterator().
    Use TypeDecl.superInterfaces().iterator() instead.

2017-12-30  Version 8.1.0

  * Many compatibility bug fixes.
  * Type inference improvements.
  * Pretty-printing improvements.
  * Many attributes were renamed, removed, added, or redesigned.
  * Stack Map Frames bytecode attributes are now generated by all Java 6+ backends.
  * The Java 6 backend now outputs bytecode version 50 (was 49).
  * The Java 7 backend now outputs bytecode version 51 (was 49).
  * The Java 8 backend now outputs bytecode version 52 (was 49).
  * The AbstractDot node type has been removed.
  * Removed several side effects in attributes. Static semantic error checking
    should now be mostly well-defined with respect to attribute purity and
    circularity.
  * Accessor methods are now generated by NTAs, replacing an imperative AST
    transformation.
  * Removed the FieldDecl list rewrite. Multiple field declarations are now
    handled by using NTAs.
  * Updated to build with JastAdd 2.2.2.
  * Circular NTAs are now used as the rewrite implementation, for safer
    rewrite evaluation.
  * Fixed order dependencies in name classification rewrites.
  * Replaced imperative enclosing variables transformation with on-demand
    generation using NTAs during code generation.
  * Replaced enum index transformations by using NTAs instead.
  * Bridge methods are now generated on demand using NTAs, instead of using
    imperative AST transformations.
  * Replaced implicit enum member rewrites by NTAs.
  * Replaced enum constructor transformation by NTAs.

2017-11-28  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Rewrote numeric literal handling in the Java 7 module.
    The NumericLiteral type was changed into an interface, which
    IntegerLiteral and LongLiteral inherit from.
    The Java 7 module no longer replaces the Java 4 Literals.ast file,
    instead the Java 7 module only adds the IllegalLiteral class to the
    grammar. The rewrite that was used to specialize numeric literals
    has been removed.
    * Fixed an error that caused numeric literal constructors to
    not properly initialize numeric literals.
    * Removed java7/frontend/Constant.jadd (replaced by
    java4/frontend/Constant.jadd).

2017-11-17  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * The attribute TypeDecl.toString() now returns the typeName() value.
    This makes it easier to debug type analysis code.

2017-11-16  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * The attribute TypeDecl.enclosingMemberDecl() is now defined for
    all member declarations (was previously undefined for fields).

2017-09-13  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Fixed an error in parse name resolution that caused certain qualified
    names to fail to resolve correctly.
    * Removed the AbstractDot type from the abstract grammar. The Dot type
    replaces any previous use of AbstractDot.  This change simplifies
    the abstract grammar, but it also means that extensions must be updated.
    Extensions should be updated by replacing any use of AbstractDot by Dot.

2017-04-22  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Renamed TypeDecl.enclosingBlock() to enclosingMemberDecl.
    * Added attribute enclosingBlock() in Expr, for computing
    the directly enclosing statement block.
    * Added TypeVariable.firstBound() to compute the first type bound of a
    type variable.

2017-04-21  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Modified the typeName() attribute of WildcardType, WildcardExtendsType,
    and WildcardSuperType to improve readability.
    This removes the "wildcard." prefix.
    * A new AST class has been added: SubstitutedTypeVariable.
    This class represents type variables that should have their type bounds
    substituted. A new NTA list child named SubstTypeParam has been
    added to ParTypeDecl and ParInterfaceDecl, containing substituted type
    variables.

2017-04-20  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added internal option type to handle missing/undefined values.

2017-04-12  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added ASTNode.toSet() to replace a null SimpleSet by an empty set.

2017-04-11  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added the method ASTNode.sourceLocation(), which returns
    the location of a node in the format "filename:line".

2016-10-17  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added separate error messages for default constructor problems.  This
    removes the need for full error checking on default constructors and
    enables generating more descriptive error messages.

2016-04-01  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Redesigned name resolution rewrites. ParseName nodes now contain
    multiple name parts and they are rewritten together at the same time.
    This simplifies the rewrite process for ParseName nodes during syntactic
    classification, and removes the need for rewriting Dot nodes.

2016-03-30  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Redesigned generic type substitution. Type variables are no longer
    substituted in the synthetic parameterized type declarations, instead
    type variable substitution happens during type lookup.
    Added two new AST node types: GenericMethodDeclErased and
    GenericConstructorDeclErased.
    The abstract grammar rules for ParClassDecl, ParInterfaceDecl,
    RawClassDecl, and RawInterfaceDecl have been changed.

2016-03-22  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Removed the List subtype BodyDeclList because it could cause null
    pointer exceptions when inherited attributes were evaluated on NTA
    children of BodyDeclList.
    * Added a new BodyDecl subtype named SubstitutedBodyDecl. This is used for
    generic type substitution of body declarations in generic types. This
    replaces the old BodyDeclList NTAs.
    * Removed the unecessary node types
    VariableArityParameterDeclarationSubstituted and
    ParameterDeclarationSubstituted.

2016-03-08  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added helper methods to build default bytecode reader and Java parser:
    Program.defaultBytecodeReader() and Program.defaultJavaParser().

2016-02-24  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Removed rewriting of EnumDecl. Implicit members in EnumDecl are now
    generated using NTAs instead of by rewriting the EnumDecl.
    * Removed side effects used to generate accessor methods. Accessor
    methods are instead generated using declarative NTAs.
    * Removed the ASTNode.transformation() method which walked over the AST
    to add accessor methods etc.
    * Removed ASTNode.clear() which was used to clear AST nodes after code
    generation (used side effects).

2016-02-23  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Replaced enum constructor transformation side effects by using the new
    nonterminal attribute ConstructorDecl.transformedEnumConstructor().

2016-02-22  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Replaced bridge method generation side effects by using an NTA and
    collection attribute. Bridge methods are no longer generated during
    the transformation phase. Bridge methods are now generated on demand
    during code generation.

2016-02-20  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Replaced the side effects used to add the "$assertionsDisabled" field
    to a class by using NTAs instead. Assert statements have a new NTA called
    "transformed()" which evaluates to the transformed form of the statement.
    The $assertionsDisabled field is also generated using an NTA.

2016-02-19  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Replaced enum switch transformation side effects. NTAs are now used to
    generate extra fields and methods needed for enum switch statements
    instead of using side effects to modify the BodyDecl list of a TypeDecl.
    Also removed the side effects which modified the actual SwitchStmt and
    nested ConstCase nodes.

    * Removed side effects used to generate bytecode for ClassAccess in the
    Java 4 backend module. This changes the bytecode generation in Java 4
    mode, and may make it incompatible with Java 4 JVMs. ExtendJ should no
    longer implicitly support Java 4, since we have not tested the Java 4
    support for a long time and it is not reasonable to try to support Java 4
    bytecode generation any longer.

2016-02-12  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Replaced FieldDecl list rewrites.

    FieldDecl nodes were previously rewritten to individual FieldDeclaration
    nodes in BodyDecl lists using a list rewrite. List rewrites are a complicated
    feature in JastAdd with some performance and correctness problems. Migrating
    from list rewrites has the potential of improving performance and enabling
    some interesting optimizations in JastAdd attribute evaluation.

    In order to remove FieldDecl list rewrites, the AST nodes FieldDeclaration and
    VariableDeclaration were removed from the abstract grammar. These have been
    replaced by FieldDeclarator and VariableDeclarator, both inheriting from the
    abstract type Declarator. A FieldDecl node now has a Declarator list that
    contains FieldDeclarator nodes and which correspond the individual fields
    declared in a single FieldDecl. A VarDeclStmt has had its VariableDecl list
    replaced by a Declarator list containing VariableDeclarator nodes.

    EnumConstant nodes behave much like FieldDecl nodes, but like the old
    FieldDeclaration nodes they declare only a single field. EnumConstant used to
    inherit from FieldDeclaration due to the many similarities between these nodes
    and due to the similar methods used in code generation. Since FieldDeclaration
    has been removed, and the corresponding code generation methods were moved to
    FieldDeclarator, which is not a BodyDecl subtype, EnumConstant had to be
    changed a bit to work after the refactoring. EnumConstant now as some
    additional attribute and method declarations that were previously inherited
    from FieldDeclaration.


2016-02-04  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added Modifiers and TypeAccess:Access NTAs in VariableDecl.  This
    eliminated the need for the SingleDecl* NTA in VarDeclStmt.  This also
    made VariableDeclaration redundant, so it has been removed from the
    abstract grammar. Extensions using VariableDeclaration should switch to
    using VariableDecl instead, and extensions using
    VarDeclStmt.getSingleDecl(x) should use VarDeclStmt.getVariableDecl(x).

2015-12-15  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added robust set org.jastadd.util.RobustSet. This is used to track
    loaded compilation units in a way that allows simultaneous iteration
    over compilation units. This happens in the Frontend.run method.

2015-10-14  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Refactored pretty printing. Pretty printing aspects are now generated
    from template files in the new pretty-print/ directory.

2015-10-05  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added documentation comment parsing.

2015-07-30  Jesper Öqvist <joqvist@google.com>

    * BytecodeParser methods now let IOExceptions escape instead of catching
    them and calling System.exit(1).
    * Moved common code from BytecodeParser classes to an abstract base class
    named AbstractClassfileParser.

2015-06-18  Jesper Öqvist <joqvist@google.com>

    * Isolated header part of java4/parser/Preamble.parser to
    java4/parser/Header.parser. This makes it easier to change the parser
    package and import declarations.
    * Isolated header part of java4/scanner/Preamble.flex to
    java4/scanner/Header.flex. This makes it easier to change the scanner
    package and import declarations.

2015-05-31  Jesper Öqvist <joqvist@google.com>

    * Removed deprecated Frontend.process method
    * Program.lookupLibType is now an inter-type method (was syn attribute)

2015-04-16  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * The TypeDecl.isReifiable attribute was moved from the Java 7 extension
    to the Java 5 extension and is now declared in the new file
    java5/frontend/ReifiableTypes.jrag

2015-04-14  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * TypeDecl.isCheckedException() now returns true if the type is a subtype of
    java.lang.RuntimeException or java.lang.Error.
    * TypeDecl.isUncheckedException() is now exactly the inverse of
    TypeDecl.isCheckedException().
    * The two above attributes have approximately inverted their behaviour
    and now work opposite to how they used to work. The naming of the
    attributes was likely an error to begin with because isCheckedException
    actually did the exact same thing that isUncheckedException should always
    have done!

2015-03-31  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Implemented explicit type bounds checking. This was previously
    part of the subtype checking which produced incorrect results in the
    form of missing errors for incompatible types.

2015-03-09  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * The Program.LibCompilationUnit NTA should no longer be populated with
    null values. The Program.getCompilationUnit method was changed to a lazy
    attribute backing the LibCompilationUnit NTA. This attribute is checked
    first for nullness before accessing the NTA.
    * Program.lookupType(String,String) no longer returns null when the type
    is not found, instead the UnknownType instance is returned.

2015-03-03  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * JavaDumpTree now ignores semantic errors
    * Improved ParseName rewriting. Many identifiers are not classified during
    parsing. The classification instead happens on demand during semantic
    analysis using rewrites. Previously these classification rewrites had
    several stages, for example, first rewrite to AmbiguousAccess and then
    rewrite to the final access node. After some refactoring this rewrite
    process is now single-staged. This makes the rewrite conditions for the
    remaining rewrites simpler, and removes the need for the node types
    AmbiguousAccess and PackageOrTypeAccess, so these have been removed from the
    grammar.  The NameType class was replaced by an enum, and the
    NameType.NO_NAME constant is now replaced by NameType.NOT_CLASSIFIED.  The
    NameType.METHOD_NAME constant was removed due to not being used.

2015-02-24  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Frontend and backend main classes have been moved to the new source
    directories src/frontend-main and src/backend-main, respectively. The
    JastAddJVersion class which is used by these main classes to obtain a
    version number was moved to src/frontend-main. This change makes it
    easier for extensions to build without the ExtendJ main classes, which
    may be undesired in extensions. Extensions that need these classes will
    need to add the new source directories to their classpath.

2015-02-17  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Add duplicate entries in localMethodsSignatureMap to enable duplicate
    inherited method checking.

2015-02-13  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Renamed the superinterfacesIterator method to interfacesIterator and
    added declaration of interfacesIterator on TypeDecl. This means that
    interfaces are now iterated over using the same iterator for both
    ClassDecl and InterfaceDecl.
    * Moved declaration of interfacesMethodsIterator from ClassDecl to
    the superclass TypeDecl.

2015-02-11  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Renamed the [ConstructorInvocation] child of ConstructorDecl to
    ParsedConstructorInvocation. This child should no longer be used to store
    implicit constructor invocations. Added new NTA child
    /ImplicitConstructorInvocation/ to represent the implicit constructor
    invocations, if needed, and added attributes named
    hasConstructorInvocation and getConstructorInvocation to mimic the former
    ConstructorInvocation child.  These changes allow for implicit constructor
    invocations to be generated while still retaining the original, parsed,
    constructor invocation in the AST.

2015-02-05  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Replaced emitEvalBranch by branchTrue and branchFalse.
    * Throw error if the constant pool overflows.

2015-01-30  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added type lookup caches for improved type lookup.
    * Fixed error where a library type could be incorrectly reported as
    duplicate declarations when local declarations in source files on the
    source path contained the same type. This issue was caused by library
    type lookups only working as intended with types having the same name
    as the containing compilation unit.

2015-01-29  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Improved numeric literal parsing and error messages

2014-08-11  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Replaced the errorCheck method by the errors and warnings methods.
    The errorCheck method took collections as arguments, where the semantic
    problems were inserted. The preferred method is to just fetch the
    internal collections of the compilation unit.

2014-07-23  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added -XstructuredPrint flag to ExtendJ main class

2014-06-04  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Removed implicit constructor list rewrites
        - Renamed isDefaultConstructor() to isImplicitConstructor()

    * Removed variable declaration list rewrites
        - VarDeclStmt is no longer rewritten to a separate VariableDeclaration
          statements.
        - VarDeclStmt now has an NTA list of single declarations named
          SingleDecl
        - VariableDeclaration no longer inherits from Stmt.
    Since VariableDeclaration is now a child of VarDeclStmt some inherited
    attributes needed to be changed in order to properly propagate values to
    VariableDeclaration nodes.

2014-06-02  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Merged Erik Hogemans Java 8 module.

2014-05-13  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Fixed errors in the Expr.canBeTrue() and Expr.canBeFalse() attributes.
    * The code generator now tries to avoid redundant GOTOs after conditional
    branches.

2014-05-05  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Fixed pretty printing problem for annotation declarations
    (the `@` in `@interface` was omitted)
    * Added -XprettyPrint command-line flag which will cause pretty printing
    of the source files
    * Added -XdumpTree command-line flag which will cause dumping the abstract
    syntax tree of the parsed source files

2014-04-15  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * The ClassDecl.superclass() method now returns non-null values.  In the
    case where the method would previously return null it now returns
    unknownType() instead. The return type was also changed to TypeDecl.

2014-03-06  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Argument files expansion has been improved. Argument files are now
    expanded in-place in the argument list, they may contain comments (`#`)
    and quoted strings, and they can be escaped by a double
    at-sign (`@@file` becomes `@file`).

2014-03-03  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Made conflicting interface method declaration error more descriptive.

2014-02-27  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Fixed annotation-related bytecode generation error.

2014-02-26  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Improved method access type errors -- void type expressions
      as a method argument now has its own error message.
    * Fixed problem in this access and super access error checking
      causing incorrect error messages to be reported for this/super
      accesses in explicit constructor invocations.

2014-02-25  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Source file processing order is now determined by the command line
      argument order.

2014-02-24  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * ExtendJ now reports all semantic errors in all compilation units
    before aborting the compilation
    * Fixed definite assignment analysis problem for assignment expressions.
      Used fix suggested by Erik Hogeman.
    * Fixed definite assignment analysis problem for method accesses.
      Used fix suggested by Erik Hogeman.
    * Fixed errors in effectively final analysis for various expressions.
    * Fixed annotation element type analysis error.

2014-02-23  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added -debug option to abstract compiler frontend. This option debugs
    extra debug checks during code generation for method binding correctness.

2014-02-22  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Changed final field assignment error messages to be more descriptive

2014-02-21  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Refactored field and variable initializer code generation

2014-02-19  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Removed the `AssignExpr.sourceType()` attribute

2014-02-07  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added method to initialize an empty ClassPath.

2014-01-16  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Gave instanceof expressions higher precedence than other relational
    expressions. This solves a shift-reduce conflict in the parser grammar and
    still parses all valid relational expressions because relational
    expressions are in practice non-associative.

2014-01-15  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added `PathPart.getPath()` method which returns the path (to jar, folder
    or file) that the `PathPart` represents.

2014-01-14  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * ExtendJ now gives an error message and fails to compile if something
    not recognized as a valid option or a filename is given on the
    command-line
    * ExtendJ now fails to compile if the output directory does not exist
    * Documented all methods in the `Frontend` class
    * ExtendJ now uses the same exit codes as Javac
    * Deprecated the `Frontend.process` method - will be replaced by
    `Frontend.run` which returns compile error codes.
    * Added `Frontend(String,String)` constructor taking the compiler name and
    version so that it is not necessary to override the `name()` and
    `version()` methods.
    * The `Frontend.processArgs()` method now has return type int, rather than
    void. Returning nonzero from `processArgs()` will abort the compilation
    and cause the compiler to exit with an exit code indicating configuration
    error.

2014-01-13  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Improved performance significantly by adding some caching back into the
    classpath handling code.
    * Renamed `FilePath` to `SourceFilePath`.
    * Added `ClassPath` class which contains classpath configuration. This
    class lazily initializes itself when needed.
    * Replaced `PathPart.packages()` with `PathPart.hasPackage(String)`.
    * `FolderPath` does not scan entire directory structure for packages, only
    polls single directory for each `hasPackage` query.
    * `JarFilePath` caches the package index so that subsequent `hasPackage`
    queries are faster.

2014-01-11  Görel Hedin <gorel.hedin@cs.lth.se>

    * Added option -nowarn for disabling warning messages.

2014-01-07  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Fixed error where some things were not properly pretty-printed in
    semantic error messages
    * Changed the error messages for:
        + imported type conflicting with visible type error
        + method invocation type error (added argument index)
        + qualified this access error (added enclosing type name)

2013-12-19  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Refactored classpath handling. PathPart is now abstract and all concrete
    subtypes are immutable. Classpaths must now be explicitly initialized
    before parsing compilation units by calling Program.initPaths().  This
    means that we can skip checking if the paths should be initialized before
    every type lookup but it also means there is a bigger burden of making
    sure the paths have been properly initialized before parsing.

2013-12-18  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Changed the semantics of TypeDecl.destinationPath and changed where
    ExtendJ generates classfiles to better match the javac behaviour

2013-12-12  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Removed TestServer because it was unused

2013-11-20  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added ASTNode.prettyPrint() method which will replace toString as the
    pretty-printing method
    * ASTNode.toString() no longer pretty-prints AST nodes

2013-09-06  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added TokenCounter frontend class

2013-08-30  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * ExtendJ no longer generates JSR/RET bytecode instructions - finally
    blocks are inlined where needed

    * Empty finally blocks do not generate bytcode

    * Added explicit AST node to generate code for the implicit
    monitor exit call for synchronized blocks


2013-08-29  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * ExtendJ now generates classfiles for imported types that are imported
    from source
    * Split src/java directory into src/frontend and src/backend

2013-08-12  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Removed BranchPropagation interface
    * Refactored branch target analysis
    * Removed some `instanceof` use

2013-08-11  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Changed the branchTarget method into an inherited attribute and improved
    its performance. Rather than collecting all branches for each potential
    target statement and testing if any of those is the current branch it
    simply tests the branch statement against each possible target statement
    directly.

2013-08-10  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * The collectFinally method has been replaced by the
    inherited enclosingFinally attribute. All enclosing finally
    hosts can be found by repeatedly evaluating the new attribute.
    This allows lazier evaluation and fixes some problems with the
    old imperative method.

2013-06-04  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Renamed PlaceholderMethodDecl to StandInMethodDecl

2013-06-03  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Fixed annotation bytecode bug affecting Class-valued annotation
    attributes

2013-05-31  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Fixed error that caused single static imports to work like
    on-demand static imports

2013-05-30  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Fixed generic method type inference error
    * Reduced code duplication in Java 7 module by separating some
    aspects into separate files in the Java 4 module

2013-05-25  Jesper Öqvist <jesper@llbit.se>

    * Java support level is now included in the version string given by
    -version

2013-05-22  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Added -profile option to generate profile data

2013-05-19  Jesper Öqvist <jesper@llbit.se>

    * Renamed SuperClassAccess children to SuperClass
    * Renamed SuperInterfaceId child to SuperInterface

2013-05-06  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Refactored AssertStmt: `AssertStmt ::= Condition:Expr [Message:Expr]`

2013-04-12  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Reorganized source tree
    * Merged frontend/backend directories - one module per Java version
    * Added Java 6 module
    * Building of jar files and documentation is handled by toplevel
    Ant script
    * Only one toplevel ReadMe and license file
    * Removed extraneous DiffTask class

2013-02-13  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Version 7.1 released

2013-01-25  Jesper Öqvist <jesper@llbit.se>

    * Removed unused import java.util.LinkedHashSet

2013-01-23  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Moved PathPart and subclasses to separate .jadd file in Java1.4Frontend
    * Improved name checking error messages for TypeDecl
    * Package names are double-checked against canonical file names in
    order to avoid some problems on case-insensitive file systems.
    Trac ticket: http://svn.cs.lth.se/trac/jastadd-trac/ticket/99

2013-01-10  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Fixed error in Java7Frontend/JavaPrettyPrinter.
      Properly escape backslash file separator.

2013-01-07  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Don't add system property `java.class.path` to classpath

2012-11-26  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Version 7.0 released

2012-11-23  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Updated to JastAdd2 version R20121122 (r889)

2012-11-14  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Updated to JastAdd2 version R20121114 (r887)

2012-11-09  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Updated to latest JastAdd2 version

2012-11-06  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * Fixed errors in parser rule for annotations, now it is closer to the JLS.
    Trac ticket: http://svn.cs.lth.se/trac/jastadd-trac/ticket/87

2012-11-02  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * ExtendJ prints an error message and exits with nonzero exit code when
    an unexpected exception occurs
    * Fixed error causing NPE during ParMethodDecl type argument substitution
    Trac ticket: http://svn.cs.lth.se/trac/jastadd-trac/ticket/86

2012-11-01  Jesper Öqvist <jesper.oqvist@cs.lth.se>

    * All type accesses in accessor methods should be qualified
      Trac ticket: http://svn.cs.lth.se/trac/jastadd-trac/ticket/85

2012-09-20 (JO)
    * Modified beaver.Symbol: made the value field non-final and added custom
      clone method. This fixes a "memory leak" when cloning AST nodes.

2012-09-13 (JO)
    * The addSourceFile method now returns the CompilationUnit representing
      the added source file name

2012-09-12 (ES/JO)
    * Applied patch from Emma which fixed a circular type lookup problem
      for generic types. The patch added the new inExtendsOrImplements
      attribute.

2012-07-18 (JO)
    * ExtendJ now uses the relative path to identify compilation units.
      The pathName attribute of compilation units may now be different due to
      this change.
      Using the relative path rather than the absolute path makes it simpler
      for static analysis tools to support relocation between different
      machines.

2012-06-29 (JO)
    * Made field and variable initializer type errors more verbose
    * Fixed error in type lookup that could cause duplicate compilation units
      to be added in the AST (one as a from-source CU, the other as library CU)
      See also http://svn.cs.lth.se/trac/jastadd-trac/ticket/74

2012-05-07 (JO)
    Changed the name of the Java7Backend compiler to ExtendJ (JJ7)

    Changed the name of the Java7Backend generated Jar file to JJ7.jar

2012-05-04 (JO)
    An implementation of createQualifiedAccess was added to AbstractWildcardType
    so that wildcard types do not use the default behaviour of creating a
    qualified type access with package and type name which are undefined for
    wildcard types.

    If a corresponding class file and source file have the same last modified
    timestamp, then the class file will be parsed rather than the source file.

    Final non-static fields now also receive the ConstantValue attribute when
    the value is constant.

    Fixed error that caused faulty bytecode generation when compiling an
    enhanced for statement where the loop variable was a boxed primitive type.

    Fixed definite assignment not propagating to second expression in an
    assert statement.

    Set the ACC_VARARGS flag for variable arity constructors.

2012-05-03 (JO)
    The hostType attribute now always returns the "original" TypeDecl, so for
    example a method in a generic class may be the child of a ParClassDecl but
    hostType will now point to the corresponding GenericClassDecl.
    This fixes an error where extraneous accessor methods were generated for
    some types of method access that did not require an accessor method.

2012-04-26 (JO)
    ExtendJ exits with exit code 0 if it only prints version or help
    information. The version string output by -version was also made shorter.

2012-03-24 (JO)
    Updated to latest JastAdd2 and RagDoll.

2012-03-06 (JO)
    Removed the TypeDecl.subclassWithinBody(TypeDecl) method since the
    purpose of that method was to find an enclosing class inheriting from a
    given superclass C while determining member accessibility.
    Only looking at the directly enclosing subclass of C is not sufficient to
    determine the accessibility of the field or method - all enclsing classes
    must be checked until one that can access the member is found.
    This is the puprpose of the new methods
    TypeDecl.mayAccess(Expr, FieldDeclaration)
    TypeDecl.mayAccess(MethodAccess, MethodDecl)

2012-02-18 (JO)
    Moved the Java7Backend compiler main class to
    org.jastadd.jastaddj.JavaCompiler. A main class with the same name remains
    in the default package, for backwards compatibility.

2011-12-08 (JO)
    Upgraded Beaver to version 0.9.9
    The new version of Beaver uses a new naming convention for the Beaver jar
    files, an effect of this is that the jar file used for Ant tasks is now
    called beaver-ant.jar. Extensions using Beaver in their Ant scripts by
    referencing Java1.4Frontend/tools/beaver.jar should be updated to reference
    Java1.4Frontend/tools/beaver-ant.jar instead.

2011-11-23 (JO)
    Added automatic version number update to build scripts for JJ7.

2011-09-24 (JO)
    Updated the JastAdd2 tool to version R20110924.

2011-09-15 (JO)
    Added isDefaultConstructor flag to ConstructorDecl. Pretty printing
    now ignores auto-generated default constructors. Extensions that rely on
    pretty printing to generate default constructors should refine the
    setDefaultConstructor method to make it do nothing.

2011-06-03 (JO)
    Refactored the Java AST. CatchClause is now an abstract base class
    for BasicCatch, which fills the same role that CatchClause previously had.
    Extensions that use the old CatchClause node type will have to in some
    cases move attribute refines etc. to BasicCatch.

2011-05-12 (JO)
    Modified build files to use more heap memory when running JastAdd2
    using an exec task.

2011-04-01 (JO)
    Errors and warnings are printed on the error stream instead of the
    standard output stream.

2011-08-09 (JO)
    Added build file to root ExtendJ directory with clean target that
    cleans all ExtendJ modules.

2011-08-09 (JO)
    Refactored VariableDeclaration.jrag - moved interface Variable to
    Variable.jadd