Class Wrapper

java.lang.Object
org.glassfish.pfl.dynamic.codegen.spi.Wrapper

public final class Wrapper extends Object
Main API for runtime code generation. This API generates bytecode dynamically at runtime, allowing direct construction of Class instances from the generated bytecodes. Such classes can then be instantiated and used in a running program. This can be used for a variety of advanced applications aimed at extending the Java language or providing significant performance enhancements.

The supported language is best thought of as a subset of Java 1.0.2. The following features from Java 5 and earlier are currently NOT supported:

  • Generics.
  • Annotations (this may be added at some point).
  • For loops (of any sort, but this may be added through extension at some point).
  • Enums.
  • Autoboxing.
  • Varargs methods.
  • Nested classes.
  • Compiler generated default constructors.
  • Compiler generated calls to super() in a constructor.
  • Anonymous classes.
  • do loops.
  • Static fields in interfaces.
  • Labels, or labelled break or continue.
The intent is that dynamically generated code should be a simplified form of Java, much like the original Java 1.0 definition. This moves dynamic code generation to a level much closer to Java than to raw bytecode manipulation.

As much as possible, this class uses standard Java keywords prefixed by "_" as method names. This helps to remember what the method name is for creating an if statement (_if of course). All public methods are static, and using static imports for this class is advisable: simple use

 import static org.glassfish.dynamic.codegen.spi.Wrapper.*
 
to get easy access to all of the _xxx methods.

A typical use of this class looks something like:

 _clear() ;                 // clean up any state from previous uses
                            // optional:
 _setClassLoader(cl) ;    // If you need a specific ClassLoader, set it early
                            // so that your generated code can be checked against 
                            // those classes that it references.
 _package( "YYY" ) ;        // set the package to use for the generated code
 _import( "AAA.BBB" ) ;   // repeat as needed.  As in Java, this makes "BBB"
                            // a synonym for "AAA.BBB".  Collisions are not 
                            // permitted.
 _class( ... ) ;            // _interface is used for interfaces.
 _data( ... )   ;           // define the class data members (repeat as needed)
 _initializer() ;           // define a static initializer


 _method( ... ) ;           // define a method (use _constructor for a constructor) 
 _arg( ... ) ;      // repeat as needed for the method arguments.
 _body() ;                  // begin the method body definition.
     // define the contents of the body using any of the available 
     // statements.
 _end() ; // of method
 _end() ; // of class
 _end() ; // of package
 Class<?>  newClass = _generate( ... ) ;
 
Alternatively, the last line could be

 GenericClass<T> gc = _generate( T.class, props ) ;
 
which makes it easy to create an instance of the generated class by calling:

 T instance = gc.create( <constructor args> ) ;
 

Currently only one class can be defined at a time. There is a grammar defined below that gives more detail. One small note: it is necessary to call _expr( expr ) in order to convert expr into a statement that is incorporated into a body. If this call is omitted, the generated code will NOT contain expr, leading to a difficult to find bug. I will probably fix this eventually, and treat all dangling expressions as errors.

This class provides many short utility methods that operate against a current context that is maintained in a ThreadLocal. This removes the bookkeeping that would otherwise be needed to keep track of various internal factories needed for generating statements and expressions. Note that this class is designed to be statically imported.

The point of view of the API of this class is that calls to create expressions are nested, while calls to create statements are not. That is, constructing an expression will often lead to nested method calls, but constructing a statement is done with a sequence of method calls. Note that everything could be done as a single nested method call per class, but this is unnatural and hard to debug in Java (Java is not Lisp, but you could make it look sort of like Lisp if you tried hard enough).

All of the expression methods can be called any place where an expression is valid, which basically means anywhere a statement can be defined. The other methods can only be called if the sequence of method calls is contained in the language defined by the following grammar:

 START      : _package IMPORTS CLASS _end ;

 IMPORTS            : _import IMPORTS
                    | empty ;

 CLASS      : _class CDECLS _end ;

 CDECLS     : CDECL CDECLS
                    | empty ;

 CDECL      : _data
                    | _initializer STMTS _end
                    | METHOD
                    | CONSTRUCTOR ;

 METHOD     : _method ARGS _body STMTS _end ;

 CONSTRUCTOR      : _constructor ARGS _body STMTS _end ;

 ARGS               : _arg ARGS 
                    | empty ;

 STMTS      : STMT STMTS
                    | empty ;

 STMT               : IF
                    | TRY
                    | SWITCH
                    | WHILE
                    | SIMPLE ;

 IF                 : _if STMTS _end
                    | _if STMTS _else STMTS _end ;

 TRY                : _try STMTS CATCHES _end
                    | _try STMTS _finally STMTS _end
                    | _try STMTS CATCHES _finally STMTS _end ;

 CATCHES            : _catch STMTS CATCHES
                    | empty ; 

 SWITCH     : _switch CASES 
                    | _switch CASES _default STMTS _end ;

 CASES      : _case STMTS CASES
                    | empty ;
 XXX modify this to support multiple case labels per statement list

 WHILE      : _while STMTS _end ;

 SIMPLE     : _assign 
                    | _define
                    | _return
                    | _throw
                    | _expr ;
 

Any method that requires an expression can use any expression so long as all variables references in the expression are still in scope. This means that:

  1. Variables representing data members can be referenced anywhere between the _class _body and _end.
  2. Variables representing method parameters can be referenced anywhere between the _method _body and _end.
  3. Variables representing _define statements can be referenced with in the scope of their block (that is, until the corresponding "}" in java. Here we don't use "{}" to delimit scope in the generated code).
  4. Variables representing _catch statements can be referenced until the next corresponding _catch, _finally, or _end. Any attempt to use an Expression that references a Variable that is out of scope will result in an IllegalStateException.

The _classGenerator() method is used here to get the ClassGeneratorImpl, which can then be used in the CodeGenerator API to create source code or byte code directly. Also note that Util.display can be used to dump the contents of the ClassGeneratorImpl for debugging purposes.

For convenience, methods are provided to display the AST (@see _displayAST), generate source code (@see _sourceCode), and generate byteCode (@see _byteCode).

  • Field Details

    • S_INIT

      private static final State S_INIT
    • S_DONE

      private static final State S_DONE
    • S_PACKAGE

      private static final State S_PACKAGE
    • S_CLASS

      private static final State S_CLASS
    • S_METHOD

      private static final State S_METHOD
    • S_BODY

      private static final State S_BODY
    • S_IF

      private static final State S_IF
    • S_ELSE

      private static final State S_ELSE
    • S_TRY

      private static final State S_TRY
    • S_FINAL

      private static final State S_FINAL
    • S_SWITCH

      private static final State S_SWITCH
    • S_DEFAULT

      private static final State S_DEFAULT
    • engine

      private static final StateEngine engine
    • tl

      private static ThreadLocal<Wrapper.Environment> tl
    • CODEGEN_PREFIX

      private static final String CODEGEN_PREFIX
      See Also:
    • DEBUG_PREFIX

      private static final String DEBUG_PREFIX
      See Also:
    • CLASS_GENERATION_DIRECTORY

      public static final String CLASS_GENERATION_DIRECTORY
      Set this to enable dumping the generated byte codes to a class file in the given directory.
      See Also:
    • SOURCE_GENERATION_DIRECTORY

      public static final String SOURCE_GENERATION_DIRECTORY
      Option used to enable generation of source files while generating bytecode. Set to name of directory that should contain the generated source file.
      See Also:
    • DUMP_AFTER_SETUP_VISITOR

      public static final String DUMP_AFTER_SETUP_VISITOR
      Debugging option used to dump the contents of the AST after the setup visitor runs.
      See Also:
    • TRACE_BYTE_CODE_GENERATION

      public static final String TRACE_BYTE_CODE_GENERATION
      Debugging option used to trace the byte code generation.
      See Also:
    • DUMP_CONSTANT_POOL

      public static final String DUMP_CONSTANT_POOL
      Causes contents of constant pool to be dumped.
      See Also:
    • USE_ASM_VERIFIER

      public static final String USE_ASM_VERIFIER
      Debugging option used to enable the ASM verifier, which can be helpful for debugging errors in the code generation.
      See Also:
  • Constructor Details

    • Wrapper

      private Wrapper()
  • Method Details

    • addCommonTransitions

      private static void addCommonTransitions(State state)
    • env

      private static Wrapper.Environment env()
    • _classGenerator

      public static ClassGenerator _classGenerator()
      Obtain the ClassGeneratorImpl that is constructed by the Wrapper methods. This is only needed for using Wrapper with custom vistors.
    • _setClassLoader

      public static void _setClassLoader(ClassLoader cl)
      Set the ClassLoader for this thread that will be used for validating references to pre-existing classes from generated code. Applications that use special ClassLoaders (such as the app server) should call this method before starting to generate a new Class. A good place to do this is just before the _package call.
    • _byteCode

      public static byte[] _byteCode(ClassLoader cl, Properties options)
      Generate byte codes for the current ClassGenerator. cl is used to resolve any references to other classes. options may be used to control some aspects of the code generation, such as debugging options. Supported options include DUMP_AFTER_SETUP_VISITOR, TRACE_BYTE_CODE_GENERATION, USE_ASM_VERIFIER.
    • _byteCode

      public static byte[] _byteCode(ClassGenerator cgen, ClassLoader cl, Properties options)
      Generate byte codes for the ClassGenerator. cl is used to resolve any references to other classes. options may be used to control some aspects of the code generation, such as debugging options. Supported options include DUMP_AFTER_SETUP_VISITOR, TRACE_BYTE_CODE_GENERATION, USE_ASM_VERIFIER.
    • _generate

      public static Class<?> _generate(ClassLoader cl, ProtectionDomain pd, Properties props, PrintStream ps)
      Deprecated.
      Generate a class for the current ClassGenerator. Basically equivalent to _byteCode followed by _makeClass. cl is used to resolve any references to other classes and to load the class given by the current ClassGenerator. options may be used to control some aspects of the code generation, such as debugging options.
    • _generate

      public static Class<?> _generate(ClassLoader cl, ProtectionDomain pd, Properties props)
      Deprecated.
      as of Java 11, use _generate(Class, Properties)
      Generate a class for the current ClassGenerator. Basically equivalent to _byteCode followed by _makeClass. cl is used to resolve any references to other classes and to load the class given by the current ClassGenerator. options may be used to control some aspects of the code generation, such as debugging options.
    • _generate

      private static Class<?> _generate(ClassGenerator cg, ClassLoader cl, ProtectionDomain pd, Properties props, PrintStream ps)
      Generate a class for the current ClassGenerator. Basically equivalent to _byteCode followed by _makeClass. cl is used to resolve any references to other classes and to load the class given by the current ClassGenerator. options may be used to control some aspects of the code generation, such as debugging options.
    • _generate

      public static Class<?> _generate(Class<?> anchorClass, Properties props, PrintStream ps)
      Generate a class for the current ClassGenerator, in the same classloader and package as a specified "anchor" class to which the caller has access.
      Parameters:
      anchorClass - an existing class used as a reference for the new one.
      props - options to control some aspects of the code generation, such as debugging.
      ps - a stream to which debug messages should be written, if any
      Since:
      since 4.1.0
    • _generate

      public static Class<?> _generate(Class<?> anchorClass, Properties props)
      Generate a class for the current ClassGenerator, in the same classloader and package as a specified "anchor" class to which the caller has access.
      Parameters:
      anchorClass - an existing class used as a reference for the new one.
      props - options to control some aspects of the code generation, such as debugging.
      Since:
      since 4.1.0
    • _generate

      private static Class<?> _generate(ClassGenerator cg, Class<?> anchorClass, Properties props, PrintStream ps)
      Generate a class for the current ClassGenerator. Basically equivalent to _byteCode followed by _makeClass. cl is used to resolve any references to other classes and to load the class given by the current ClassGenerator. options may be used to control some aspects of the code generation, such as debugging options.
    • _sourceCode

      public static void _sourceCode(PrintStream ps, Properties options) throws IOException
      Generate the Java source code for the current Class defined by Wrapper calls. options may be used to control some aspects of the formatting of the source code, but no options are currently defined. The generate source code is written to the PrintStream.
      Throws:
      IOException
    • _sourceCode

      public static void _sourceCode(ClassGenerator cg, PrintStream ps, Properties options) throws IOException
      Generate the Java source code for the ClassGenerator. options may be used to control some aspects of the formatting of the source code, but no options are currently defined. The generate source code is written to the PrintStream.
      Throws:
      IOException
    • _sourceCode

      public static void _sourceCode(Properties options) throws IOException
      Generate source code into a specified output directory. options must set SOURCE_GENERATION_DIRECTORY to the name of the output directory.
      Throws:
      IOException
    • _sourceCode

      public static void _sourceCode(ClassGenerator cg, Properties options) throws IOException
      Generate source code into a specified output directory. options must set SOURCE_GENERATION_DIRECTORY to the name of the output directory.
      Throws:
      IOException
    • _displayAST

      public static void _displayAST(ClassGenerator cg, PrintStream ps)
      Dump the contents of the AST for the current Class defined by Wrapper calls. The AST is dumped to the PrintStream.
    • _clear

      public static void _clear()
      Discard the current Class generated by Wrapper calls, so that another Class may be generated.
    • _s

      public static Signature _s(Type rtype, Type... types)
      Create a signature that may be used for calling a method or constructor. rtype is the return type, and types gives all of the argument types. types is empty if there are no arguments.
    • _s

      public static Signature _s(Type rtype, List<Type> types)
      Create a signature that may be used for calling a method or constructor. rtype is the return type, and types gives all of the argument types. types is empty if there are no arguments.
    • _t

      public static Type _t(String name)
      Return the reference type for the given class name. name may be either the Class name, if the full name has been imported using an _import statement, or a fully qualified Class name.
    • _void

      public static Type _void()
      Return a representation of the void type. This is used whenever a method has a void return type.
    • _boolean

      public static Type _boolean()
      Return a representation of the boolean type.
    • _byte

      static Type _byte()
      Return a representation of the byte type.
    • _short

      static Type _short()
      Return a representation of the short type.
    • _char

      static Type _char()
      Return a representation of the char type.
    • _int

      public static Type _int()
      Return a representation of the int type.
    • _long

      static Type _long()
      Return a representation of the long type.
    • _float

      static Type _float()
      Return a representation of the float type.
    • _double

      static Type _double()
      Return a representation of the double type.
    • _Object

      public static Type _Object()
      Return a representation of the java.lang.Object type.
    • _String

      public static Type _String()
      Return a representation of the java.lang.String type.
    • _Class

      public static Type _Class()
      Return a representation of the java.lang.Class type.
    • splitClassName

      public static Pair<String,String> splitClassName(String name)
      Split the class name into a pair of the package name and the unqualified class name. If name is the name of a class in the anonymous global package, the package name is "".
    • _package

      public static void _package(String name)
      _package must be called first to set the package name for this class. After _package, all required _import calls must be made, followed by one _class call. name may be "", in which case the generated class is in the default package.
    • _package

      public static void _package()
      Same as _package( "" ). Note that this method MUST be called before _class or _interface. This is a bit surprising, since Java allows omission of the package statement, but codegen requires an explicit package call.
    • _import

      public static Type _import(String name)
      Used to create short names for types. Name must be a fully qualified class name. The last name becomes the short name used in _t to look up the full type. The result Type can also be used directly.
    • _import

      public static ImportList _import()
      Return an ImportList that can be shared across multiple class generations.
    • _import

      public static void _import(ImportList ilist)
      Set the ImportList for the current class generation. Mainly useful for generating source code.
    • _class

      public static void _class(int modifiers, String name, Type superClass, Type... impls)
      Define a class. This must be followed by calls to _data, _initializer, or _method in any order.
    • _class

      public static void _class(int modifiers, String name, Type superClass, List<Type> impls)
      Define a class. This must be followed by calls to _data, _initializer, or _method in any order.
    • _interface

      public static void _interface(int modifiers, String name, Type... impls)
      Define an interface. This must be followed by calls to _method only. All _method calls must define abstract methods. Note that static data in interfaces is not currently supported.
    • _interface

      public static void _interface(int modifiers, String name, List<Type> impls)
      Define an interface. This must be followed by calls to _method only. All _method calls must define abstract methods. Note that static data in interfaces is not currently supported.
    • _data

      public static Expression _data(int modifiers, Type type, String name)
      Define a data member in a class. If static, it must be initialized in the class initializer, otherwise it must be initialized in a constructor.
    • _method

      public static void _method(int modifiers, Type type, String name, Type... exceptions)
      Begin defining a method in the current class. Must be followed first be all _arg calls for the method, then by _body(), then by any statements, and finally by _end(). _body() may be followed immediately by _end(), in which case the method has an empty body. Abstract methods must have an empty body.
    • _method

      public static void _method(int modifiers, Type type, String name, List<Type> exceptions)
      Begin defining a method in the current class. Must be followed first by all _arg calls for the method, then by _body(), then by any statements, and finally by _end(). _body() may be followed immediately by _end(), in which case the method has an empty body. Abstract methods must have an empty body.
    • _constructor

      public static void _constructor(int modifiers, Type... exceptions)
      Begin defining a constructor in the current class. Must be followed first by all _arg calls for the constructor, then by _body(), then by optional statements, and finally by _end(). Note that the first statement in any constructor must be a this() or super() call. Constructors may not have empty bodies.
    • _constructor

      public static void _constructor(int modifiers, List<Type> exceptions)
      Begin defining a constructor in the current class. Must be followed first by all _arg calls for the constructor, then by _body(), then by any statements, and finally by _end(). Note that the first statement in any constructor must be a _this() or _super() call. Constructors may not have empty bodies. Note that no default constructor is automatically generated using this API.
    • _arg

      public static Expression _arg(Type type, String name)
      Add an argument to the current method.
    • _body

      public static void _body()
      Indicates the start of the definition of the body of a method. Must be followed by 0 or more statements, and be terminated by _end().
    • _end

      public static void _end()
      Terminates the definition of the current statement, method, constructor, initializer, class, or package. Restores the context for the previous definition.
    • _expr

      public static void _expr(Expression expr)
      Indicate that expr should be executed as a statement for its side effects.
    • _assign

      public static void _assign(Expression var, Expression expr)
      Indicates an assignment statement of the form var = expr. Var must be an assignable expression, such as a local variable, a non-final field reference, ior an array index expression.
    • _define

      public static Expression _define(Type type, String name, Expression expr)
      Indicates the introduction of a new local variable initialized to the given expression.
    • _return

      public static void _return()
      Indicates the end of execution in a method. Can only occur inside a definition of a method with a void return type.
    • _return

      public static void _return(Expression expr)
      Indicates the end of execution in a method with a return of the value of the expression. The type of the expression must be assignment compatible with the return type of the enclosing method.
    • _throw

      public static void _throw(Expression expr)
      Indicates a throw statement that throws the given expression. The type of expr must support Throwable.
    • _if

      public static void _if(Expression expr)
      Indicate the start of an if statement with the given expression as the condition. All subsequent statements until the next matching _else are part of the true branch of this if statement.
    • _else

      public static void _else()
      Indicate the start of the false branch of an if statement. All subsequent statements until the next matching _end are part of the false branch of the corresponding if statement.
    • _try

      public static void _try()
      Indicate the start of a try statement. All subsequent statements until the next matching _catch or _finally are part of this try statement.
    • _catch

      public static Expression _catch(Type type, String name)
      Indicate the start of a catch clause in a try statement. All subsequent statements until the next matching _catch or _finally are part of this catch clause.
    • _finally

      public static void _finally()
      Indicate the start of a finally clause in a try statement. All subsequent statements until the next matching _end are part of this finally clause.
    • _v

      public static Expression _v(String name)
      Construct the expression that refers to the variable named name. This is looked up following the Java name scope rules.
    • _null

      public static Expression _null()
      Return the null expression.
    • _const

      public static Expression _const(boolean c)
      Return a constant expression representing the value c.
    • _const

      public static Expression _const(char c)
      Return a constant expression representing the value c.
    • _const

      public static Expression _const(byte c)
      Return a constant expression representing the value c.
    • _const

      public static Expression _const(short c)
      Return a constant expression representing the value c.
    • _const

      public static Expression _const(int c)
      Return a constant expression representing the value c.
    • _const

      public static Expression _const(long c)
      Return a constant expression representing the value c.
    • _const

      public static Expression _const(float c)
      Return a constant expression representing the value c.
    • _const

      public static Expression _const(double c)
      Return a constant expression representing the value c.
    • _const

      public static Expression _const(String c)
      Return a constant expression representing the value c.
    • _const

      public static Expression _const(Type c)
      Return a constant expression representing the value c. Here c is a type, and this corresponds to the Java ".class" reference.
    • _call

      public static Expression _call(Expression target, String ident, Signature signature, Expression... args)
      Generate a call to an instance method. The full signature must be specified.
    • _call

      public static Expression _call(Expression target, String ident, Signature signature, List<Expression> args)
      Generate a call to an instance method. The full signature must be specified.
    • _call

      public static Expression _call(Expression target, String ident, Expression... args)
      Generate a call to an instance method, using the Java method overload resolution algorithm to determine the signature.
    • _call

      public static Expression _call(Expression target, String ident, List<Expression> args)
      Generate a call to an instance method, using the Java method overload resolution algorithm to determine the signature.
    • _call

      public static Expression _call(Type target, String ident, Signature signature, Expression... args)
      Generate a call to a static method. The full signature must be specified.
    • _call

      public static Expression _call(Type target, String ident, Signature signature, List<Expression> args)
      Generate a call to a static method. The full signature must be specified.
    • _call

      public static Expression _call(Type target, String ident, Expression... args)
      Generate a call to a static method, using the Java method overload resolution algorithm to determine the signature.
    • _call

      public static Expression _call(Type target, String ident, List<Expression> args)
      Generate a call to a static method, using the Java method overload resolution algorithm to determine the signature.
    • _super

      public static Expression _super(String ident, Signature signature, Expression... exprs)
      Generate a call to an instance method in the current super class. The full signature must be specified.
    • _super

      public static Expression _super(String ident, Signature signature, List<Expression> exprs)
      Generate a call to an instance method in the current super class. The full signature must be specified.
    • _super

      public static Expression _super(String ident, Expression... exprs)
      Generate a call to an instance method in the current super class using the Java method overload resolution algorithm to determine the signature.
    • _super

      public static Expression _super(String ident, List<Expression> exprs)
      Generate a call to an instance method in the current super class using the Java method overload resolution algorithm to determine the signature.
    • _super

      public static Expression _super(Signature signature, Expression... exprs)
      Invoke a superclass constructor as the first statement in a constructor for a class. The full signature must be specified. This may only be used as the first expression in a constructor. Every constructor must begin with either a super(...) call or a this(...) call.
    • _super

      public static Expression _super(Signature signature, List<Expression> exprs)
      Invoke a superclass constructor as the first statement in a constructor for a class. The full signature must be specified. This may only be used as the first expression in a constructor. Every constructor must begin with either a super(...) call or a this(...) call.
    • _super

      public static Expression _super(List<Expression> exprs)
      Invoke a superclass constructor as the first statement in a constructor for a class using the Java method overload resolution algorithm to determine the signature. This may only be used as the first expression in a constructor. Every constructor must begin with either a super(...) call or a this(...) call.
    • _super

      public static Expression _super(Expression... exprs)
      Invoke a superclass constructor as the first statement in a constructor for a class using the Java method overload resolution algorithm to determine the signature. This may only be used as the first expression in a constructor. Every constructor must begin with either a super(...) call or a this(...) call.
    • _this

      public static Expression _this(Signature signature, Expression... exprs)
      Invoke another constructor as the first statement in a constructor for a class. The full signature must be specified. This may only be used as the first expression in a constructor. Every constructor must begin with either a super(...) call or a this(...) call.
    • _this

      public static Expression _this(Signature signature, List<Expression> exprs)
      Invoke another constructor as the first statement in a constructor for a class. The full signature must be specified. This may only be used as the first expression in a constructor. Every constructor must begin with either a super(...) call or a this(...) call.
    • _this

      public static Expression _this(Expression... exprs)
      Invoke another constructor as the first statement in a constructor for a class using the Java method overload resolution algorithm to determine the signature. This may only be used as the first expression in a constructor. Every constructor must begin with either a super(...) call or a this(...) call.
    • _this

      public static Expression _this(List<Expression> exprs)
      Invoke another constructor as the first statement in a constructor for a class using the Java method overload resolution algorithm to determine the signature. This may only be used as the first expression in a constructor. Every constructor must begin with either a super(...) call or a this(...) call.
    • _binary

      private static Expression _binary(Expression left, ExpressionFactory.BinaryOperator op, Expression right)
    • _ne

      public static Expression _ne(Expression left, Expression right)
      Create an expression representing the application of the != operator to the left and right expressions in the form (left op right).
    • _cast

      public static Expression _cast(Type type, Expression expr)
      Create an expression representing the type cast of expr to type.
    • _new

      public static Expression _new(Type type, Signature signature, Expression... args)
      Create an expression representing the construction of a new instance of the given type using the constructor with the given signature and the list of expressions as arguments.
    • _new

      public static Expression _new(Type type, Signature signature, List<Expression> args)
      Create an expression representing the construction of a new instance of the given type using the constructor with the given signature and the list of expressions as arguments.
    • _new

      public static Expression _new(Type type, Expression... args)
      Create an expression representing the construction of a new instance of the given type using the constructor with the signature determined by the Java method overload resolution algorithm and the list of expressions as arguments.
    • _new

      public static Expression _new(Type type, List<Expression> args)
      Create an expression representing the construction of a new instance of the given type using the constructor with the signature determined by the Java method overload resolution algorithm and the list of expressions as arguments.
    • _new_array_init

      public static Expression _new_array_init(Type type, Expression... args)
      Create an expression representing the construction of a new array with the given component type using the given expressions to initialize the array. We really only support single dimensional arrays here. The size of the resulting array is the number of expressions given here.
    • _new_array_init

      public static Expression _new_array_init(Type type, List<Expression> args)
      Create an expression representing the construction of a new array with the given component type using the given expressions to initialize the array. We really only support single dimensional arrays here. The size of the resulting array is the number of expressions given here. Equivalent to new A[] = { exprList }.
    • _thisClass

      public static Type _thisClass()
      Return the type of the current class.
    • _this

      public static Expression _this()
      Return an expression representing "this".
    • _field

      public static Expression _field(Expression expr, String fieldName)
      Return an expression used to access a field in an object given by expr. This expression may appear on the left side of an assignment statement.
    • _field

      public static Expression _field(Type type, String fieldName)
      Return an expression used to access a static data member in a class given by the type. This expression may appear on the left side of an assignment statement (but probably shouldn't).
    • _index

      public static Expression _index(Expression expr, Expression index)
      Return an expression used to access an element in an array given by expr. This expression may appear on the left side of an assignment statement.