sun.tools.tree

Class Expression

java.lang.Object

sun.tools.tree.Node

sun.tools.tree.Expression

All Implemented Interfaces:

java.lang.Cloneable, Constants, RuntimeConstants

Direct Known Subclasses:

BooleanExpression, DoubleExpression, FloatExpression, IdentifierExpression, InlineMethodExpression, InlineNewInstanceExpression, IntegerExpression, LongExpression, NullExpression, StringExpression, 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 Summary

Fields inherited from interface sun.tools.java.Constants

ABSTRACT, ACCM_CLASS, ACCM_FIELD, ACCM_INNERCLASS, ACCM_MEMBER, ACCM_METHOD, ADD, AND, ARRAY, ARRAYACCESS, ASGADD, ASGBITAND, ASGBITOR, ASGBITXOR, ASGDIV, ASGLSHIFT, ASGMUL, ASGREM, ASGRSHIFT, ASGSUB, ASGURSHIFT, ASSIGN, ATT_ALL, ATT_ALLCLASSES, ATT_CODE, BITAND, BITNOT, BITOR, BITXOR, BOOLEAN, BOOLEANVAL, BREAK, BYTE, BYTEVAL, CASE, CAST, CATCH, CHAR, CHARVAL, CLASS, COLON, COMMA, COMMENT, COND, CONST, CONTINUE, CONVERT, CS_BINARY, CS_CHECKED, CS_COMPILED, CS_NOTFOUND, CS_PARSED, CS_SOURCE, CS_UNDECIDED, CS_UNDEFINED, CT_BLOCK, CT_BRANCH_FALSE, CT_BRANCH_TRUE, CT_CASE, CT_FIKT_METHOD, CT_FIKT_RET, CT_FIRST_KIND, CT_LAST_KIND, CT_METHOD, CT_SWITH_WO_DEF, DEC, DECLARATION, DEFAULT, DIV, DO, DOUBLE, DOUBLEVAL, ELSE, EQ, ERROR, EXPR, EXPRESSION, EXTENDS, F_COVDATA, F_COVERAGE, F_DEBUG_LINES, F_DEBUG_SOURCE, F_DEBUG_VARS, F_DEPENDENCIES, F_DEPRECATION, F_DUMP, F_ERRORSREPORTED, F_OPT, F_OPT_INTERCLASS, F_PRINT_DEPENDENCIES, F_STRICTDEFAULT, F_VERBOSE, F_VERSION12, F_WARNINGS, FALSE, FIELD, FINAL, FINALLY, FLOAT, FLOATVAL, FOR, GE, GOTO, GT, idAppend, idClass, idClassInit, idClone, idCode, idConstantValue, idCoverageTable, idDeprecated, idDocumentation, IDENT, idExceptions, idFinallyReturnValue, idGetClass, idInit, idInnerClasses, idJavaIoSerializable, idJavaLang, idJavaLangClass, idJavaLangCloneable, idJavaLangError, idJavaLangException, idJavaLangObject, idJavaLangRuntimeException, idJavaLangString, idJavaLangStringBuffer, idJavaLangThrowable, idLength, idLineNumberTable, idLocalVariableTable, idNew, idNull, idSourceFile, idStar, idSuper, idSynthetic, idThis, idToString, idTYPE, idValueOf, IF, IMPLEMENTS, IMPORT, INC, INLINEMETHOD, INLINENEWINSTANCE, INLINERETURN, INSTANCEOF, INT, INTERFACE, INTVAL, LBRACE, LE, LENGTH, LONG, LONGVAL, LPAREN, LSHIFT, LSQBRACKET, LT, M_ABSTRACT, M_ANONYMOUS, M_DEPRECATED, M_FINAL, M_INLINEABLE, M_INTERFACE, M_LOCAL, M_NATIVE, M_PRIVATE, M_PROTECTED, M_PUBLIC, M_STATIC, M_STRICTFP, M_SYNCHRONIZED, M_SYNTHETIC, M_TRANSIENT, M_VOLATILE, MAXFILESIZE, MAXLINENUMBER, METHOD, MM_CLASS, MM_FIELD, MM_MEMBER, MM_METHOD, MUL, NATIVE, NE, NEG, NEW, NEWARRAY, NEWFROMNAME, NEWINSTANCE, NOT, NULL, opNames, opPrecedence, OR, PACKAGE, paraDeprecated, POS, POSTDEC, POSTINC, PREDEC, prefixAccess, prefixArray, prefixClass, prefixLoc, prefixThis, prefixVal, PREINC, PRIVATE, PROTECTED, PUBLIC, QUESTIONMARK, RBRACE, REM, RETURN, RPAREN, RSHIFT, RSQBRACKET, SEMICOLON, SHORT, SHORTVAL, SIG_INNERCLASS, SIGC_INNERCLASS, STAT, STATIC, STRICTFP, STRINGVAL, SUB, SUPER, SWITCH, SYNCHRONIZED, TC_ARRAY, TC_BOOLEAN, TC_BYTE, TC_CHAR, TC_CLASS, TC_DOUBLE, TC_ERROR, TC_FLOAT, TC_INT, TC_LONG, TC_METHOD, TC_NULL, TC_SHORT, TC_VOID, THIS, THROW, THROWS, TM_ARRAY, TM_BOOLEAN, TM_BYTE, TM_CHAR, TM_CLASS, TM_DOUBLE, TM_ERROR, TM_FLOAT, TM_INT, TM_INT32, TM_INTEGER, TM_LONG, TM_METHOD, TM_NULL, TM_NUM32, TM_NUM64, TM_NUMBER, TM_REAL, TM_REFERENCE, TM_SHORT, TM_VOID, tracing, TRANSIENT, TRUE, TRY, TYPE, URSHIFT, VARDECLARATION, VOID, VOLATILE, WHEREOFFSETBITS, WHILE

Fields inherited from interface sun.tools.java.RuntimeConstants

ACC_ABSTRACT, ACC_FINAL, ACC_INTERFACE, ACC_NATIVE, ACC_PRIVATE, ACC_PROTECTED, ACC_PUBLIC, ACC_STATIC, ACC_STRICT, ACC_SUPER, ACC_SYNCHRONIZED, ACC_TRANSIENT, ACC_VOLATILE, CONSTANT_CLASS, CONSTANT_DOUBLE, CONSTANT_FIELD, CONSTANT_FLOAT, CONSTANT_INTEGER, CONSTANT_INTERFACEMETHOD, CONSTANT_INVOKEDYNAMIC, CONSTANT_LONG, CONSTANT_METHOD, CONSTANT_METHODHANDLE, CONSTANT_METHODTYPE, CONSTANT_NAMEANDTYPE, CONSTANT_STRING, CONSTANT_UNICODE, CONSTANT_UTF8, JAVA_DEFAULT_MINOR_VERSION, JAVA_DEFAULT_VERSION, JAVA_MAGIC, JAVA_MAX_SUPPORTED_MINOR_VERSION, JAVA_MAX_SUPPORTED_VERSION, JAVA_MIN_SUPPORTED_VERSION, opc_aaload, opc_aastore, opc_aconst_null, opc_aload, opc_aload_0, opc_aload_1, opc_aload_2, opc_aload_3, opc_anewarray, opc_areturn, opc_arraylength, opc_astore, opc_astore_0, opc_astore_1, opc_astore_2, opc_astore_3, opc_athrow, opc_baload, opc_bastore, opc_bipush, opc_breakpoint, opc_caload, opc_castore, opc_checkcast, opc_d2f, opc_d2i, opc_d2l, opc_dadd, opc_daload, opc_dastore, opc_dcmpg, opc_dcmpl, opc_dconst_0, opc_dconst_1, opc_ddiv, opc_dead, opc_dload, opc_dload_0, opc_dload_1, opc_dload_2, opc_dload_3, opc_dmul, opc_dneg, opc_drem, opc_dreturn, opc_dstore, opc_dstore_0, opc_dstore_1, opc_dstore_2, opc_dstore_3, opc_dsub, opc_dup, opc_dup_x1, opc_dup_x2, opc_dup2, opc_dup2_x1, opc_dup2_x2, opc_f2d, opc_f2i, opc_f2l, opc_fadd, opc_faload, opc_fastore, opc_fcmpg, opc_fcmpl, opc_fconst_0, opc_fconst_1, opc_fconst_2, opc_fdiv, opc_fload, opc_fload_0, opc_fload_1, opc_fload_2, opc_fload_3, opc_fmul, opc_fneg, opc_frem, opc_freturn, opc_fstore, opc_fstore_0, opc_fstore_1, opc_fstore_2, opc_fstore_3, opc_fsub, opc_getfield, opc_getstatic, opc_goto, opc_goto_w, opc_i2b, opc_i2c, opc_i2d, opc_i2f, opc_i2l, opc_i2s, opc_iadd, opc_iaload, opc_iand, opc_iastore, opc_iconst_0, opc_iconst_1, opc_iconst_2, opc_iconst_3, opc_iconst_4, opc_iconst_5, opc_iconst_m1, opc_idiv, opc_if_acmpeq, opc_if_acmpne, opc_if_icmpeq, opc_if_icmpge, opc_if_icmpgt, opc_if_icmple, opc_if_icmplt, opc_if_icmpne, opc_ifeq, opc_ifge, opc_ifgt, opc_ifle, opc_iflt, opc_ifne, opc_ifnonnull, opc_ifnull, opc_iinc, opc_iload, opc_iload_0, opc_iload_1, opc_iload_2, opc_iload_3, opc_imul, opc_ineg, opc_instanceof, opc_invokedynamic, opc_invokeinterface, opc_invokespecial, opc_invokestatic, opc_invokevirtual, opc_ior, opc_irem, opc_ireturn, opc_ishl, opc_ishr, opc_istore, opc_istore_0, opc_istore_1, opc_istore_2, opc_istore_3, opc_isub, opc_iushr, opc_ixor, opc_jsr, opc_jsr_w, opc_l2d, opc_l2f, opc_l2i, opc_label, opc_ladd, opc_laload, opc_land, opc_lastore, opc_lcmp, opc_lconst_0, opc_lconst_1, opc_ldc, opc_ldc_w, opc_ldc2_w, opc_ldiv, opc_lload, opc_lload_0, opc_lload_1, opc_lload_2, opc_lload_3, opc_lmul, opc_lneg, opc_lookupswitch, opc_lor, opc_lrem, opc_lreturn, opc_lshl, opc_lshr, opc_lstore, opc_lstore_0, opc_lstore_1, opc_lstore_2, opc_lstore_3, opc_lsub, opc_lushr, opc_lxor, opc_monitorenter, opc_monitorexit, opc_multianewarray, opc_new, opc_newarray, opc_nop, opc_pop, opc_pop2, opc_putfield, opc_putstatic, opc_ret, opc_return, opc_saload, opc_sastore, opc_sipush, opc_swap, opc_tableswitch, opc_try, opc_wide, opcLengths, opcNames, SIG_ARRAY, SIG_BOOLEAN, SIG_BYTE, SIG_CHAR, SIG_CLASS, SIG_DOUBLE, SIG_ENDCLASS, SIG_ENDMETHOD, SIG_FLOAT, SIG_INT, SIG_LONG, SIG_METHOD, SIG_PACKAGE, SIG_SHORT, SIG_VOID, SIGC_ARRAY, SIGC_BOOLEAN, SIGC_BYTE, SIGC_CHAR, SIGC_CLASS, SIGC_DOUBLE, SIGC_ENDCLASS, SIGC_ENDMETHOD, SIGC_FLOAT, SIGC_INT, SIGC_LONG, SIGC_METHOD, SIGC_PACKAGE, SIGC_SHORT, SIGC_VOID, T_BOOLEAN, T_BYTE, T_CHAR, T_CLASS, T_DOUBLE, T_FLOAT, T_INT, T_LONG, T_SHORT

Method Summary

Methods

Modifier and Type	Method and Description
Vset	check(Environment env, Context ctx, Vset vset, java.util.Hashtable<java.lang.Object,java.lang.Object> exp)
Vset	checkAmbigName(Environment env, Context ctx, Vset vset, java.util.Hashtable<java.lang.Object,java.lang.Object> exp, UnaryExpression loc) Check something that might be an AmbiguousName (refman 6.5.2).
Vset	checkAssignOp(Environment env, Context ctx, Vset vset, java.util.Hashtable<java.lang.Object,java.lang.Object> exp, Expression outside)
sun.tools.tree.ConditionVars	checkCondition(Environment env, Context ctx, Vset vset, java.util.Hashtable<java.lang.Object,java.lang.Object> exp) Check a condition.
void	checkCondition(Environment env, Context ctx, Vset vset, java.util.Hashtable<java.lang.Object,java.lang.Object> exp, sun.tools.tree.ConditionVars cvars)
Vset	checkInitializer(Environment env, Context ctx, Vset vset, Type t, java.util.Hashtable<java.lang.Object,java.lang.Object> exp)
Vset	checkLHS(Environment env, Context ctx, Vset vset, java.util.Hashtable<java.lang.Object,java.lang.Object> exp)
Vset	checkValue(Environment env, Context ctx, Vset vset, java.util.Hashtable<java.lang.Object,java.lang.Object> exp) Check an expression
void	code(Environment env, Context ctx, Assembler asm)
void	codeValue(Environment env, Context ctx, Assembler asm)
Expression	copyInline(Context ctx) Create a copy of the expression for method inlining
int	costInline(int thresh, Environment env, Context ctx) The cost of inlining this expression.
boolean	equals(boolean b)
boolean	equals(Identifier id)
boolean	equals(int i) Check if the expression is known to be equal to a given value.
boolean	equals(java.lang.String s)
boolean	equalsDefault() Check if the expression is equal to its default static value
Expression	firstConstructor() Check if the first thing is a constructor invocation
boolean	fitsType(Environment env, Context ctx, Type t) See if this expression fits in the given type.
boolean	fitsType(Environment env, Type t) Deprecated. (for backward compatibility)
sun.tools.tree.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.
Expression	getImplementation() Type checking may assign a more complex implementation to an innocuous-looking expression (like an identifier).
Type	getType()
sun.tools.tree.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.
java.lang.Object	getValue() Return the constant value.
Expression	inline(Environment env, Context ctx) Inline.
Expression	inlineLHS(Environment env, Context ctx)
Expression	inlineValue(Environment env, Context ctx)
protected java.lang.StringBuffer	inlineValueSB(Environment env, Context ctx, java.lang.StringBuffer buffer) Attempt to evaluate this expression.
boolean	isConstant() Return true if constant, according to JLS 15.27.
boolean	isNonNull() Check if the expression cannot be a null reference.
boolean	isNull() Check if the expression must be a null reference.
Expression	order() Order the expression based on precedence
void	print(java.io.PrintStream out) Print

Methods inherited from class sun.tools.tree.Node

clone, convert, getOp, getWhere, toString

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

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()

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 java.lang.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(java.lang.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

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,
              java.util.Hashtable<java.lang.Object,java.lang.Object> exp)

Check an expression

checkInitializer

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

check

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

checkLHS

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

getAssigner

public sun.tools.tree.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 sun.tools.tree.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,
                 java.util.Hashtable<java.lang.Object,java.lang.Object> exp,
                 Expression outside)

checkAmbigName

public Vset checkAmbigName(Environment env,
                  Context ctx,
                  Vset vset,
                  java.util.Hashtable<java.lang.Object,java.lang.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 sun.tools.tree.ConditionVars checkCondition(Environment env,
                                          Context ctx,
                                          Vset vset,
                                          java.util.Hashtable<java.lang.Object,java.lang.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,
                  java.util.Hashtable<java.lang.Object,java.lang.Object> exp,
                  sun.tools.tree.ConditionVars cvars)

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 java.lang.StringBuffer inlineValueSB(Environment env,
                                   Context ctx,
                                   java.lang.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.

codeValue

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

code

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

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(java.io.PrintStream out)

Print

Overrides:

print in class Node