Package org.glassfish.rmic.tools.tree

Class Expression

java.lang.Object
org.glassfish.rmic.tools.tree.Node
org.glassfish.rmic.tools.tree.Expression
All Implemented Interfaces:
Cloneable, Constants, RuntimeConstants
Direct Known Subclasses:
ConstantExpression, IdentifierExpression, InlineMethodExpression, InlineNewInstanceExpression, ThisExpression, TypeExpression, UnaryExpression
public class Expression extends Node
WARNING: The contents of this source file are not part of any supported API. Code that depends on them does so at its own risk: they are subject to change or removal without notice.

  • Field Details

  • Constructor Details

    • Expression

      Expression(int op, long where, Type type)
      Constructor

  • Method Details

    • getImplementation

      public Expression getImplementation()
      Type checking may assign a more complex implementation to an innocuous-looking expression (like an identifier). Return that implementation, or the original expression itself if there is no special implementation.

      This appears at present to be dead code, and is not called from within javac. Access to the implementation generally occurs within the same class, and thus uses the underlying field directly.

    • getType

      public Type getType()

    • precedence

      int precedence()
      Return the precedence of the operator

    • order

      public Expression order()
      Order the expression based on precedence

    • isConstant

      public boolean isConstant()
      Return true if constant, according to JLS 15.27. A constant expression must inline away to a literal constant.

    • getValue

      public Object getValue()
      Return the constant value.

    • equals

      public boolean equals(int i)
      Check if the expression is known to be equal to a given value. Returns false for any expression other than a literal constant, thus should be called only after simplification (inlining) has been performed.

    • equals

      public boolean equals(boolean b)

    • equals

      public boolean equals(Identifier id)

    • equals

      public boolean equals(String s)

    • isNull

      public boolean isNull()
      Check if the expression must be a null reference.

    • isNonNull

      public boolean isNonNull()
      Check if the expression cannot be a null reference.

    • equalsDefault

      public boolean equalsDefault()
      Check if the expression is equal to its default static value

    • toType

      Type toType(Environment env, Context ctx)
      Convert an expresion to a type

    • fitsType

      public boolean fitsType(Environment env, Context ctx, Type t)
      See if this expression fits in the given type. This is useful because some larger numbers fit into smaller types.

      If it is an "int" constant expression, inline it, if necessary, to examine its numerical value. See JLS 5.2 and 15.24.

    • fitsType

      @Deprecated public boolean fitsType(Environment env, Type t)
      Deprecated.
      (for backward compatibility)

    • checkValue

      public Vset checkValue(Environment env, Context ctx, Vset vset, Hashtable<Object,Object> exp)
      Check an expression

    • checkInitializer

      public Vset checkInitializer(Environment env, Context ctx, Vset vset, Type t, Hashtable<Object,Object> exp)

    • check

      public Vset check(Environment env, Context ctx, Vset vset, Hashtable<Object,Object> exp)

    • checkLHS

      public Vset checkLHS(Environment env, Context ctx, Vset vset, Hashtable<Object,Object> exp)

    • getAssigner

      public FieldUpdater getAssigner(Environment env, Context ctx)
      Return a FieldUpdater object to be used in updating the value of the location denoted by this, which must be an expression suitable for the left-hand side of an assignment. This is used for implementing assignments to private fields for which an access method is required. Returns null if no access method is needed, in which case the assignment is handled in the usual way, by direct access. Only simple assignment expressions are handled here Assignment operators and pre/post increment/decrement operators are are handled by 'getUpdater' below.

      Called during the checking phase.

    • getUpdater

      public FieldUpdater getUpdater(Environment env, Context ctx)
      Return a FieldUpdater object to be used in updating the value of the location denoted by this, which must be an expression suitable for the left-hand side of an assignment. This is used for implementing the assignment operators and the increment/decrement operators on private fields that require an access method, e.g., uplevel from an inner class. Returns null if no access method is needed.

      Called during the checking phase.

    • checkAssignOp

      public Vset checkAssignOp(Environment env, Context ctx, Vset vset, Hashtable<Object,Object> exp, Expression outside)

    • checkAmbigName

      public Vset checkAmbigName(Environment env, Context ctx, Vset vset, Hashtable<Object,Object> exp, UnaryExpression loc)
      Check something that might be an AmbiguousName (refman 6.5.2). A string of dot-separated identifiers might be, in order of preference:
    • a variable name followed by fields or types
    • a type name followed by fields or types
    • a package name followed a type and then fields or types If a type name is found, it rewrites itself as a TypeExpression. If a node decides it can only be a package prefix, it sets its type to Type.tPackage. The caller must detect this and act appropriately to verify the full package name.

    • checkCondition

      public ConditionVars checkCondition(Environment env, Context ctx, Vset vset, Hashtable<Object,Object> exp)
      Check a condition. Return a ConditionVars(), which indicates when which variables are set if the condition is true, and which are set if the condition is false.

    • checkCondition

      public void checkCondition(Environment env, Context ctx, Vset vset, Hashtable<Object,Object> exp, ConditionVars cvars)

    • eval

      Expression eval()
      Evaluate. Attempt to compute the value of an expression node. If all operands are literal constants of the same kind (e.g., IntegerExpression nodes), a new constant node of the proper type is returned representing the value as computed at compile-time. Otherwise, the original node 'this' is returned.

    • simplify

      Expression simplify()
      Simplify. Attempt to simplify an expression node by returning a semantically- equivalent expression that is presumably less costly to execute. There is some overlap with the intent of 'eval', as compile-time evaluation of conditional expressions and the short-circuit boolean operators is performed here. Other simplifications include logical identities involving logical negation and comparisons. If no simplification is possible, the original node 'this' is returned. It is assumed that the children of the node have previously been recursively simplified and evaluated. A result of 'null' indicates that the expression may be elided entirely.

    • inline

      public Expression inline(Environment env, Context ctx)
      Inline. Recursively simplify each child of an expression node, destructively replacing the child with the simplified result. Also attempts to simplify the current node 'this', and returns the simplified result. The name 'inline' is somthing of a misnomer, as these methods are responsible for compile-time expression simplification in general. The 'eval' and 'simplify' methods apply to a single expression node only -- it is 'inline' and 'inlineValue' that drive the simplification of entire expressions.

    • inlineValue

      public Expression inlineValue(Environment env, Context ctx)

    • inlineValueSB

      protected StringBuffer inlineValueSB(Environment env, Context ctx, StringBuffer buffer)
      Attempt to evaluate this expression. If this expression yields a value, append it to the StringBuffer `buffer'. If this expression cannot be evaluated at this time (for example if it contains a division by zero, a non-constant subexpression, or a subexpression which "refuses" to evaluate) then return `null' to indicate failure. It is anticipated that this method will be called to evaluate concatenations of compile-time constant strings. The call originates from AddExpression#inlineValue(). See AddExpression#inlineValueSB() for detailed comments.

    • inlineLHS

      public Expression inlineLHS(Environment env, Context ctx)

    • costInline

      public int costInline(int thresh, Environment env, Context ctx)
      The cost of inlining this expression. This cost controls the inlining of methods, and does not determine the compile-time simplifications performed by 'inline' and friends.

    • codeBranch

      void codeBranch(Environment env, Context ctx, Assembler asm, Label lbl, boolean whenTrue)
      Code

    • codeValue

      public void codeValue(Environment env, Context ctx, Assembler asm)

    • code

      public void code(Environment env, Context ctx, Assembler asm)

    • codeLValue

      int codeLValue(Environment env, Context ctx, Assembler asm)

    • codeLoad

      void codeLoad(Environment env, Context ctx, Assembler asm)

    • codeStore

      void codeStore(Environment env, Context ctx, Assembler asm)

    • ensureString

      void ensureString(Environment env, Context ctx, Assembler asm) throws ClassNotFound, AmbiguousMember
      Convert this expression to a string.
      Throws:
      ClassNotFound
      AmbiguousMember

    • codeAppend

      void codeAppend(Environment env, Context ctx, Assembler asm, ClassDeclaration sbClass, boolean needBuffer) throws ClassNotFound, AmbiguousMember
      Convert this expression to a string and append it to the string buffer on the top of the stack. If the needBuffer argument is true, the string buffer needs to be created, initialized, and pushed on the stack, first.
      Throws:
      ClassNotFound
      AmbiguousMember

    • codeDup

      void codeDup(Environment env, Context ctx, Assembler asm, int items, int depth)
      Code

    • codeConversion

      void codeConversion(Environment env, Context ctx, Assembler asm, Type f, Type t)

    • firstConstructor

      public Expression firstConstructor()
      Check if the first thing is a constructor invocation

    • copyInline

      public Expression copyInline(Context ctx)
      Create a copy of the expression for method inlining

    • print

      public void print(PrintStream out)
      Print
      Overrides:
      print in class Node