duke@1: /*
mcimadamore@1178: * Copyright (c) 1999, 2012, Oracle and/or its affiliates. All rights reserved.
duke@1: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@1: *
duke@1: * This code is free software; you can redistribute it and/or modify it
duke@1: * under the terms of the GNU General Public License version 2 only, as
ohair@554: * published by the Free Software Foundation. Oracle designates this
duke@1: * particular file as subject to the "Classpath" exception as provided
ohair@554: * by Oracle in the LICENSE file that accompanied this code.
duke@1: *
duke@1: * This code is distributed in the hope that it will be useful, but WITHOUT
duke@1: * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@1: * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@1: * version 2 for more details (a copy is included in the LICENSE file that
duke@1: * accompanied this code).
duke@1: *
duke@1: * You should have received a copy of the GNU General Public License version
duke@1: * 2 along with this work; if not, write to the Free Software Foundation,
duke@1: * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@1: *
ohair@554: * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
ohair@554: * or visit www.oracle.com if you need additional information or have any
ohair@554: * questions.
duke@1: */
duke@1:
duke@1: package com.sun.tools.javac.comp;
duke@1:
mcimadamore@674: import com.sun.tools.javac.tree.JCTree;
mcimadamore@674: import com.sun.tools.javac.tree.JCTree.JCTypeCast;
mcimadamore@820: import com.sun.tools.javac.tree.TreeInfo;
duke@1: import com.sun.tools.javac.util.*;
duke@1: import com.sun.tools.javac.util.List;
duke@1: import com.sun.tools.javac.code.*;
duke@1: import com.sun.tools.javac.code.Type.*;
mcimadamore@299: import com.sun.tools.javac.code.Symbol.*;
mcimadamore@1186: import com.sun.tools.javac.comp.Resolve.InapplicableMethodException;
mcimadamore@1114: import com.sun.tools.javac.comp.Resolve.VerboseResolutionMode;
mcimadamore@1114: import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
duke@1:
duke@1: import static com.sun.tools.javac.code.TypeTags.*;
duke@1:
duke@1: /** Helper class for type parameter inference, used by the attribution phase.
duke@1: *
jjg@581: *
This is NOT part of any supported API.
jjg@581: * If you write code that depends on this, you do so at your own risk.
duke@1: * This code and its internal interfaces are subject to change or
duke@1: * deletion without notice.
duke@1: */
duke@1: public class Infer {
duke@1: protected static final Context.Key inferKey =
duke@1: new Context.Key();
duke@1:
duke@1: /** A value for prototypes that admit any type, including polymorphic ones. */
duke@1: public static final Type anyPoly = new Type(NONE, null);
duke@1:
duke@1: Symtab syms;
duke@1: Types types;
mcimadamore@396: Check chk;
mcimadamore@299: Resolve rs;
mcimadamore@1114: Log log;
mcimadamore@89: JCDiagnostic.Factory diags;
duke@1:
duke@1: public static Infer instance(Context context) {
duke@1: Infer instance = context.get(inferKey);
duke@1: if (instance == null)
duke@1: instance = new Infer(context);
duke@1: return instance;
duke@1: }
duke@1:
duke@1: protected Infer(Context context) {
duke@1: context.put(inferKey, this);
duke@1: syms = Symtab.instance(context);
duke@1: types = Types.instance(context);
mcimadamore@299: rs = Resolve.instance(context);
mcimadamore@1114: log = Log.instance(context);
mcimadamore@396: chk = Check.instance(context);
mcimadamore@89: diags = JCDiagnostic.Factory.instance(context);
mcimadamore@89: ambiguousNoInstanceException =
mcimadamore@89: new NoInstanceException(true, diags);
mcimadamore@89: unambiguousNoInstanceException =
mcimadamore@89: new NoInstanceException(false, diags);
mcimadamore@299: invalidInstanceException =
mcimadamore@299: new InvalidInstanceException(diags);
mcimadamore@299:
duke@1: }
duke@1:
mcimadamore@1186: public static class InferenceException extends InapplicableMethodException {
duke@1: private static final long serialVersionUID = 0;
duke@1:
mcimadamore@299: InferenceException(JCDiagnostic.Factory diags) {
mcimadamore@689: super(diags);
duke@1: }
mcimadamore@299: }
mcimadamore@299:
mcimadamore@299: public static class NoInstanceException extends InferenceException {
mcimadamore@299: private static final long serialVersionUID = 1;
mcimadamore@299:
mcimadamore@299: boolean isAmbiguous; // exist several incomparable best instances?
mcimadamore@299:
mcimadamore@299: NoInstanceException(boolean isAmbiguous, JCDiagnostic.Factory diags) {
mcimadamore@299: super(diags);
mcimadamore@299: this.isAmbiguous = isAmbiguous;
duke@1: }
duke@1: }
mcimadamore@299:
mcimadamore@299: public static class InvalidInstanceException extends InferenceException {
mcimadamore@299: private static final long serialVersionUID = 2;
mcimadamore@299:
mcimadamore@299: InvalidInstanceException(JCDiagnostic.Factory diags) {
mcimadamore@299: super(diags);
mcimadamore@299: }
mcimadamore@299: }
mcimadamore@299:
mcimadamore@89: private final NoInstanceException ambiguousNoInstanceException;
mcimadamore@89: private final NoInstanceException unambiguousNoInstanceException;
mcimadamore@299: private final InvalidInstanceException invalidInstanceException;
duke@1:
duke@1: /***************************************************************************
duke@1: * Auxiliary type values and classes
duke@1: ***************************************************************************/
duke@1:
duke@1: /** A mapping that turns type variables into undetermined type variables.
duke@1: */
mcimadamore@1251: List makeUndetvars(List tvars) {
mcimadamore@1251: List undetvars = Type.map(tvars, fromTypeVarFun);
mcimadamore@1251: for (Type t : undetvars) {
mcimadamore@1251: UndetVar uv = (UndetVar)t;
mcimadamore@1251: uv.hibounds = types.getBounds((TypeVar)uv.qtype);
mcimadamore@1251: }
mcimadamore@1251: return undetvars;
mcimadamore@1251: }
mcimadamore@1251: //where
mcimadamore@1251: Mapping fromTypeVarFun = new Mapping("fromTypeVarFun") {
mcimadamore@1251: public Type apply(Type t) {
mcimadamore@1251: if (t.tag == TYPEVAR) return new UndetVar(t);
mcimadamore@1251: else return t.map(this);
duke@1: }
mcimadamore@1251: };
duke@1:
duke@1: /***************************************************************************
duke@1: * Mini/Maximization of UndetVars
duke@1: ***************************************************************************/
duke@1:
duke@1: /** Instantiate undetermined type variable to its minimal upper bound.
duke@1: * Throw a NoInstanceException if this not possible.
duke@1: */
duke@1: void maximizeInst(UndetVar that, Warner warn) throws NoInstanceException {
mcimadamore@828: List hibounds = Type.filter(that.hibounds, errorFilter);
mcimadamore@1251: if (that.eq.isEmpty()) {
mcimadamore@828: if (hibounds.isEmpty())
duke@1: that.inst = syms.objectType;
mcimadamore@828: else if (hibounds.tail.isEmpty())
mcimadamore@828: that.inst = hibounds.head;
mcimadamore@210: else
mcimadamore@828: that.inst = types.glb(hibounds);
mcimadamore@1251: } else {
mcimadamore@1251: that.inst = that.eq.head;
duke@1: }
mcimadamore@210: if (that.inst == null ||
mcimadamore@298: that.inst.isErroneous())
mcimadamore@210: throw ambiguousNoInstanceException
mcimadamore@210: .setMessage("no.unique.maximal.instance.exists",
mcimadamore@828: that.qtype, hibounds);
duke@1: }
duke@1:
mcimadamore@828: private Filter errorFilter = new Filter() {
mcimadamore@828: @Override
mcimadamore@828: public boolean accepts(Type t) {
mcimadamore@828: return !t.isErroneous();
mcimadamore@828: }
mcimadamore@828: };
mcimadamore@828:
jjg@110: /** Instantiate undetermined type variable to the lub of all its lower bounds.
duke@1: * Throw a NoInstanceException if this not possible.
duke@1: */
duke@1: void minimizeInst(UndetVar that, Warner warn) throws NoInstanceException {
mcimadamore@828: List lobounds = Type.filter(that.lobounds, errorFilter);
mcimadamore@1251: if (that.eq.isEmpty()) {
mcimadamore@828: if (lobounds.isEmpty())
duke@1: that.inst = syms.botType;
mcimadamore@828: else if (lobounds.tail.isEmpty())
mcimadamore@828: that.inst = lobounds.head.isPrimitive() ? syms.errType : lobounds.head;
duke@1: else {
mcimadamore@828: that.inst = types.lub(lobounds);
mcimadamore@5: }
jjg@110: if (that.inst == null || that.inst.tag == ERROR)
duke@1: throw ambiguousNoInstanceException
duke@1: .setMessage("no.unique.minimal.instance.exists",
mcimadamore@828: that.qtype, lobounds);
mcimadamore@1251: } else {
mcimadamore@1251: that.inst = that.eq.head;
duke@1: }
duke@1: }
duke@1:
mcimadamore@1186: Type asUndetType(Type t, List undetvars) {
mcimadamore@1186: return types.subst(t, inferenceVars(undetvars), undetvars);
mcimadamore@1186: }
mcimadamore@1186:
mcimadamore@1186: List inferenceVars(List undetvars) {
mcimadamore@1186: ListBuffer tvars = ListBuffer.lb();
mcimadamore@1186: for (Type uv : undetvars) {
mcimadamore@1186: tvars.append(((UndetVar)uv).qtype);
mcimadamore@1186: }
mcimadamore@1186: return tvars.toList();
mcimadamore@1186: }
mcimadamore@1186:
duke@1: /***************************************************************************
duke@1: * Exported Methods
duke@1: ***************************************************************************/
duke@1:
duke@1: /** Try to instantiate expression type `that' to given type `to'.
duke@1: * If a maximal instantiation exists which makes this type
duke@1: * a subtype of type `to', return the instantiated type.
duke@1: * If no instantiation exists, or if several incomparable
duke@1: * best instantiations exist throw a NoInstanceException.
duke@1: */
mcimadamore@1268: public List instantiateUninferred(DiagnosticPosition pos,
mcimadamore@1268: List undetvars,
mcimadamore@1268: List tvars,
mcimadamore@1268: MethodType mtype,
mcimadamore@1268: Attr.ResultInfo resultInfo,
mcimadamore@299: Warner warn) throws InferenceException {
mcimadamore@1268: Type to = resultInfo.pt;
mcimadamore@1268: if (to.tag == NONE) {
mcimadamore@1268: to = mtype.getReturnType().tag <= VOID ?
mcimadamore@1268: mtype.getReturnType() : syms.objectType;
mcimadamore@1268: }
mcimadamore@1268: Type qtype1 = types.subst(mtype.getReturnType(), tvars, undetvars);
mcimadamore@753: if (!types.isSubtype(qtype1,
mcimadamore@753: qtype1.tag == UNDETVAR ? types.boxedTypeOrType(to) : to)) {
duke@1: throw unambiguousNoInstanceException
mcimadamore@689: .setMessage("infer.no.conforming.instance.exists",
mcimadamore@1268: tvars, mtype.getReturnType(), to);
duke@1: }
duke@1:
mcimadamore@1251: List insttypes;
mcimadamore@1251: while (true) {
mcimadamore@1251: boolean stuck = true;
mcimadamore@1251: insttypes = List.nil();
mcimadamore@1251: for (Type t : undetvars) {
mcimadamore@1251: UndetVar uv = (UndetVar)t;
mcimadamore@1268: if (uv.inst == null && (uv.eq.nonEmpty() || !Type.containsAny(uv.hibounds, tvars))) {
mcimadamore@1251: maximizeInst((UndetVar)t, warn);
mcimadamore@1251: stuck = false;
mcimadamore@1251: }
mcimadamore@1251: insttypes = insttypes.append(uv.inst == null ? uv.qtype : uv.inst);
mcimadamore@1251: }
mcimadamore@1268: if (!Type.containsAny(insttypes, tvars)) {
mcimadamore@1251: //all variables have been instantiated - exit
mcimadamore@1251: break;
mcimadamore@1251: } else if (stuck) {
mcimadamore@1251: //some variables could not be instantiated because of cycles in
mcimadamore@1251: //upper bounds - provide a (possibly recursive) default instantiation
mcimadamore@1251: insttypes = types.subst(insttypes,
mcimadamore@1268: tvars,
mcimadamore@1268: instantiateAsUninferredVars(undetvars, tvars));
mcimadamore@1251: break;
mcimadamore@1251: } else {
mcimadamore@1251: //some variables have been instantiated - replace newly instantiated
mcimadamore@1251: //variables in remaining upper bounds and continue
mcimadamore@1251: for (Type t : undetvars) {
mcimadamore@1251: UndetVar uv = (UndetVar)t;
mcimadamore@1268: uv.hibounds = types.subst(uv.hibounds, tvars, insttypes);
mcimadamore@1251: }
mcimadamore@1251: }
mcimadamore@635: }
mcimadamore@1268: return insttypes;
duke@1: }
mcimadamore@1251:
mcimadamore@1251: /**
mcimadamore@1251: * Infer cyclic inference variables as described in 15.12.2.8.
mcimadamore@1251: */
mcimadamore@1178: private List instantiateAsUninferredVars(List undetvars, List tvars) {
mcimadamore@1178: Assert.check(undetvars.length() == tvars.length());
mcimadamore@1251: ListBuffer insttypes = ListBuffer.lb();
mcimadamore@1251: ListBuffer todo = ListBuffer.lb();
mcimadamore@1251: //step 1 - create fresh tvars
mcimadamore@635: for (Type t : undetvars) {
mcimadamore@635: UndetVar uv = (UndetVar)t;
mcimadamore@1251: if (uv.inst == null) {
mcimadamore@1251: TypeSymbol fresh_tvar = new TypeSymbol(Flags.SYNTHETIC, uv.qtype.tsym.name, null, uv.qtype.tsym.owner);
mcimadamore@1251: fresh_tvar.type = new TypeVar(fresh_tvar, types.makeCompoundType(uv.hibounds), null);
mcimadamore@1251: todo.append(uv);
mcimadamore@1251: uv.inst = fresh_tvar.type;
mcimadamore@1251: }
mcimadamore@1251: insttypes.append(uv.inst);
mcimadamore@635: }
mcimadamore@1251: //step 2 - replace fresh tvars in their bounds
mcimadamore@1178: List formals = tvars;
mcimadamore@1251: for (Type t : todo) {
mcimadamore@1251: UndetVar uv = (UndetVar)t;
mcimadamore@1251: TypeVar ct = (TypeVar)uv.inst;
mcimadamore@1251: ct.bound = types.glb(types.subst(types.getBounds(ct), tvars, insttypes.toList()));
mcimadamore@1251: if (ct.bound.isErroneous()) {
mcimadamore@1251: //report inference error if glb fails
mcimadamore@1251: reportBoundError(uv, BoundErrorKind.BAD_UPPER);
mcimadamore@1251: }
mcimadamore@1178: formals = formals.tail;
mcimadamore@635: }
mcimadamore@1251: return insttypes.toList();
mcimadamore@635: }
duke@1:
duke@1: /** Instantiate method type `mt' by finding instantiations of
duke@1: * `tvars' so that method can be applied to `argtypes'.
duke@1: */
mcimadamore@1268: public Type instantiateMethod(Env env,
mcimadamore@547: List tvars,
duke@1: MethodType mt,
mcimadamore@1268: Attr.ResultInfo resultInfo,
mcimadamore@1268: Symbol msym,
mcimadamore@1268: List argtypes,
mcimadamore@1268: boolean allowBoxing,
mcimadamore@1268: boolean useVarargs,
mcimadamore@1268: Warner warn) throws InferenceException {
duke@1: //-System.err.println("instantiateMethod(" + tvars + ", " + mt + ", " + argtypes + ")"); //DEBUG
mcimadamore@1268: List undetvars = makeUndetvars(tvars);
mcimadamore@689:
mcimadamore@1268: List capturedArgs =
mcimadamore@1186: rs.checkRawArgumentsAcceptable(env, undetvars, argtypes, mt.getParameterTypes(),
mcimadamore@1186: allowBoxing, useVarargs, warn, new InferenceCheckHandler(undetvars));
duke@1:
duke@1: // minimize as yet undetermined type variables
duke@1: for (Type t : undetvars)
duke@1: minimizeInst((UndetVar) t, warn);
duke@1:
duke@1: /** Type variables instantiated to bottom */
duke@1: ListBuffer restvars = new ListBuffer();
duke@1:
mcimadamore@396: /** Undet vars instantiated to bottom */
mcimadamore@396: final ListBuffer restundet = new ListBuffer();
mcimadamore@396:
duke@1: /** Instantiated types or TypeVars if under-constrained */
duke@1: ListBuffer insttypes = new ListBuffer();
duke@1:
duke@1: /** Instantiated types or UndetVars if under-constrained */
duke@1: ListBuffer undettypes = new ListBuffer();
duke@1:
duke@1: for (Type t : undetvars) {
duke@1: UndetVar uv = (UndetVar)t;
duke@1: if (uv.inst.tag == BOT) {
duke@1: restvars.append(uv.qtype);
mcimadamore@396: restundet.append(uv);
duke@1: insttypes.append(uv.qtype);
duke@1: undettypes.append(uv);
duke@1: uv.inst = null;
duke@1: } else {
duke@1: insttypes.append(uv.inst);
duke@1: undettypes.append(uv.inst);
duke@1: }
duke@1: }
mcimadamore@1251: checkWithinBounds(tvars, undetvars, insttypes.toList(), warn);
duke@1:
mcimadamore@299: mt = (MethodType)types.subst(mt, tvars, insttypes.toList());
mcimadamore@299:
mcimadamore@1268: if (!restvars.isEmpty() && resultInfo != null) {
mcimadamore@1268: List restInferred =
mcimadamore@1268: instantiateUninferred(env.tree.pos(), restundet.toList(), restvars.toList(), mt, resultInfo, warn);
mcimadamore@1268: checkWithinBounds(tvars, undetvars,
mcimadamore@1268: types.subst(insttypes.toList(), restvars.toList(), restInferred), warn);
mcimadamore@1268: mt = (MethodType)types.subst(mt, restvars.toList(), restInferred);
mcimadamore@1268: if (rs.verboseResolutionMode.contains(VerboseResolutionMode.DEFERRED_INST)) {
mcimadamore@1268: log.note(env.tree.pos, "deferred.method.inst", msym, mt, resultInfo.pt);
mcimadamore@1268: }
duke@1: }
mcimadamore@1268:
mcimadamore@1268: if (restvars.isEmpty() || resultInfo != null) {
mcimadamore@845: // check that actuals conform to inferred formals
mcimadamore@845: checkArgumentsAcceptable(env, capturedArgs, mt.getParameterTypes(), allowBoxing, useVarargs, warn);
mcimadamore@299: }
mcimadamore@1268: // return instantiated version of method type
mcimadamore@1268: return mt;
duke@1: }
duke@1: //where
duke@1:
mcimadamore@1186: /** inference check handler **/
mcimadamore@1186: class InferenceCheckHandler implements Resolve.MethodCheckHandler {
mcimadamore@1186:
mcimadamore@1186: List undetvars;
mcimadamore@1186:
mcimadamore@1186: public InferenceCheckHandler(List undetvars) {
mcimadamore@1186: this.undetvars = undetvars;
mcimadamore@1186: }
mcimadamore@1186:
mcimadamore@1186: public InapplicableMethodException arityMismatch() {
mcimadamore@1186: return unambiguousNoInstanceException.setMessage("infer.arg.length.mismatch");
mcimadamore@1186: }
mcimadamore@1186: public InapplicableMethodException argumentMismatch(boolean varargs, Type found, Type expected) {
mcimadamore@1186: String key = varargs ?
mcimadamore@1186: "infer.varargs.argument.mismatch" :
mcimadamore@1186: "infer.no.conforming.assignment.exists";
mcimadamore@1186: return unambiguousNoInstanceException.setMessage(key,
mcimadamore@1186: inferenceVars(undetvars), found, expected);
mcimadamore@1186: }
mcimadamore@1186: public InapplicableMethodException inaccessibleVarargs(Symbol location, Type expected) {
mcimadamore@1186: return unambiguousNoInstanceException.setMessage("inaccessible.varargs.type",
mcimadamore@1186: expected, Kinds.kindName(location), location);
mcimadamore@1186: }
mcimadamore@1186: }
mcimadamore@1186:
mcimadamore@845: private void checkArgumentsAcceptable(Env env, List actuals, List formals,
mcimadamore@845: boolean allowBoxing, boolean useVarargs, Warner warn) {
mcimadamore@845: try {
mcimadamore@845: rs.checkRawArgumentsAcceptable(env, actuals, formals,
mcimadamore@845: allowBoxing, useVarargs, warn);
mcimadamore@845: }
mcimadamore@1186: catch (InapplicableMethodException ex) {
mcimadamore@845: // inferred method is not applicable
mcimadamore@845: throw invalidInstanceException.setMessage(ex.getDiagnostic());
mcimadamore@845: }
mcimadamore@845: }
mcimadamore@845:
mcimadamore@1251: /** check that type parameters are within their bounds.
mcimadamore@895: */
mcimadamore@1251: void checkWithinBounds(List tvars,
mcimadamore@1251: List undetvars,
mcimadamore@1251: List arguments,
mcimadamore@1251: Warner warn)
mcimadamore@1251: throws InvalidInstanceException {
mcimadamore@1251: List args = arguments;
mcimadamore@1251: for (Type t : undetvars) {
mcimadamore@1251: UndetVar uv = (UndetVar)t;
mcimadamore@1251: uv.hibounds = types.subst(uv.hibounds, tvars, arguments);
mcimadamore@1251: uv.lobounds = types.subst(uv.lobounds, tvars, arguments);
mcimadamore@1251: uv.eq = types.subst(uv.eq, tvars, arguments);
mcimadamore@1251: checkCompatibleUpperBounds(uv, tvars);
mcimadamore@1251: if (args.head.tag != TYPEVAR || !args.head.containsAny(tvars)) {
mcimadamore@1251: Type inst = args.head;
mcimadamore@1251: for (Type u : uv.hibounds) {
mcimadamore@1251: if (!types.isSubtypeUnchecked(inst, types.subst(u, tvars, undetvars), warn)) {
mcimadamore@1251: reportBoundError(uv, BoundErrorKind.UPPER);
mcimadamore@1251: }
mcimadamore@1251: }
mcimadamore@1251: for (Type l : uv.lobounds) {
mcimadamore@1251: if (!types.isSubtypeUnchecked(types.subst(l, tvars, undetvars), inst, warn)) {
mcimadamore@1251: reportBoundError(uv, BoundErrorKind.LOWER);
mcimadamore@1251: }
mcimadamore@1251: }
mcimadamore@1251: for (Type e : uv.eq) {
mcimadamore@1251: if (!types.isSameType(inst, types.subst(e, tvars, undetvars))) {
mcimadamore@1251: reportBoundError(uv, BoundErrorKind.EQ);
mcimadamore@1251: }
mcimadamore@1251: }
mcimadamore@1251: }
mcimadamore@1251: args = args.tail;
duke@1: }
mcimadamore@895: }
duke@1:
mcimadamore@1251: void checkCompatibleUpperBounds(UndetVar uv, List tvars) {
mcimadamore@1251: // VGJ: sort of inlined maximizeInst() below. Adding
mcimadamore@1251: // bounds can cause lobounds that are above hibounds.
mcimadamore@1251: ListBuffer hiboundsNoVars = ListBuffer.lb();
mcimadamore@1251: for (Type t : Type.filter(uv.hibounds, errorFilter)) {
mcimadamore@1251: if (!t.containsAny(tvars)) {
mcimadamore@1251: hiboundsNoVars.append(t);
mcimadamore@1251: }
duke@1: }
mcimadamore@1251: List hibounds = hiboundsNoVars.toList();
mcimadamore@1251: Type hb = null;
mcimadamore@1251: if (hibounds.isEmpty())
mcimadamore@1251: hb = syms.objectType;
mcimadamore@1251: else if (hibounds.tail.isEmpty())
mcimadamore@1251: hb = hibounds.head;
mcimadamore@1251: else
mcimadamore@1251: hb = types.glb(hibounds);
mcimadamore@1251: if (hb == null || hb.isErroneous())
mcimadamore@1251: reportBoundError(uv, BoundErrorKind.BAD_UPPER);
mcimadamore@1251: }
mcimadamore@1251:
mcimadamore@1251: enum BoundErrorKind {
mcimadamore@1251: BAD_UPPER() {
mcimadamore@1251: @Override
mcimadamore@1251: InapplicableMethodException setMessage(InferenceException ex, UndetVar uv) {
mcimadamore@1251: return ex.setMessage("incompatible.upper.bounds", uv.qtype, uv.hibounds);
mcimadamore@1251: }
mcimadamore@1251: },
mcimadamore@1251: UPPER() {
mcimadamore@1251: @Override
mcimadamore@1251: InapplicableMethodException setMessage(InferenceException ex, UndetVar uv) {
mcimadamore@1251: return ex.setMessage("inferred.do.not.conform.to.upper.bounds", uv.inst, uv.hibounds);
mcimadamore@1251: }
mcimadamore@1251: },
mcimadamore@1251: LOWER() {
mcimadamore@1251: @Override
mcimadamore@1251: InapplicableMethodException setMessage(InferenceException ex, UndetVar uv) {
mcimadamore@1251: return ex.setMessage("inferred.do.not.conform.to.lower.bounds", uv.inst, uv.lobounds);
mcimadamore@1251: }
mcimadamore@1251: },
mcimadamore@1251: EQ() {
mcimadamore@1251: @Override
mcimadamore@1251: InapplicableMethodException setMessage(InferenceException ex, UndetVar uv) {
mcimadamore@1251: return ex.setMessage("inferred.do.not.conform.to.eq.bounds", uv.inst, uv.eq);
mcimadamore@1251: }
mcimadamore@1251: };
mcimadamore@1251:
mcimadamore@1251: abstract InapplicableMethodException setMessage(InferenceException ex, UndetVar uv);
mcimadamore@1251: }
mcimadamore@1251: //where
mcimadamore@1251: void reportBoundError(UndetVar uv, BoundErrorKind bk) {
mcimadamore@1251: throw bk.setMessage(uv.inst == null ? ambiguousNoInstanceException : invalidInstanceException, uv);
duke@1: }
mcimadamore@674:
mcimadamore@674: /**
mcimadamore@674: * Compute a synthetic method type corresponding to the requested polymorphic
mcimadamore@820: * method signature. The target return type is computed from the immediately
mcimadamore@820: * enclosing scope surrounding the polymorphic-signature call.
mcimadamore@674: */
mcimadamore@1239: Type instantiatePolymorphicSignatureInstance(Env env,
mcimadamore@674: MethodSymbol spMethod, // sig. poly. method or null if none
mcimadamore@820: List argtypes) {
mcimadamore@674: final Type restype;
mcimadamore@716:
mcimadamore@820: //The return type for a polymorphic signature call is computed from
mcimadamore@820: //the enclosing tree E, as follows: if E is a cast, then use the
mcimadamore@820: //target type of the cast expression as a return type; if E is an
mcimadamore@820: //expression statement, the return type is 'void' - otherwise the
mcimadamore@820: //return type is simply 'Object'. A correctness check ensures that
mcimadamore@820: //env.next refers to the lexically enclosing environment in which
mcimadamore@820: //the polymorphic signature call environment is nested.
mcimadamore@820:
mcimadamore@820: switch (env.next.tree.getTag()) {
jjg@1127: case TYPECAST:
mcimadamore@820: JCTypeCast castTree = (JCTypeCast)env.next.tree;
mcimadamore@820: restype = (TreeInfo.skipParens(castTree.expr) == env.tree) ?
mcimadamore@820: castTree.clazz.type :
mcimadamore@820: syms.objectType;
mcimadamore@820: break;
jjg@1127: case EXEC:
mcimadamore@820: JCTree.JCExpressionStatement execTree =
mcimadamore@820: (JCTree.JCExpressionStatement)env.next.tree;
mcimadamore@820: restype = (TreeInfo.skipParens(execTree.expr) == env.tree) ?
mcimadamore@820: syms.voidType :
mcimadamore@820: syms.objectType;
mcimadamore@820: break;
mcimadamore@820: default:
mcimadamore@820: restype = syms.objectType;
mcimadamore@674: }
mcimadamore@674:
mcimadamore@674: List paramtypes = Type.map(argtypes, implicitArgType);
mcimadamore@674: List exType = spMethod != null ?
mcimadamore@674: spMethod.getThrownTypes() :
mcimadamore@674: List.of(syms.throwableType); // make it throw all exceptions
mcimadamore@674:
mcimadamore@674: MethodType mtype = new MethodType(paramtypes,
mcimadamore@674: restype,
mcimadamore@674: exType,
mcimadamore@674: syms.methodClass);
mcimadamore@674: return mtype;
mcimadamore@674: }
mcimadamore@674: //where
mcimadamore@674: Mapping implicitArgType = new Mapping ("implicitArgType") {
mcimadamore@674: public Type apply(Type t) {
mcimadamore@674: t = types.erasure(t);
mcimadamore@674: if (t.tag == BOT)
mcimadamore@674: // nulls type as the marker type Null (which has no instances)
mcimadamore@674: // infer as java.lang.Void for now
mcimadamore@674: t = types.boxedClass(syms.voidType).type;
mcimadamore@674: return t;
mcimadamore@674: }
mcimadamore@674: };
mcimadamore@895: }