1.1 --- a/src/share/classes/com/sun/tools/javac/comp/Check.java Mon Mar 26 15:27:51 2012 +0100
1.2 +++ b/src/share/classes/com/sun/tools/javac/comp/Check.java Mon Mar 26 15:28:22 2012 +0100
1.3 @@ -269,23 +269,6 @@
1.4 else return syms.errType;
1.5 }
1.6
1.7 - /** Report a type error.
1.8 - * @param pos Position to be used for error reporting.
1.9 - * @param problem A string describing the error.
1.10 - * @param found The type that was found.
1.11 - * @param req The type that was required.
1.12 - */
1.13 - Type typeError(DiagnosticPosition pos, Object problem, Type found, Type req) {
1.14 - log.error(pos, "prob.found.req",
1.15 - problem, found, req);
1.16 - return types.createErrorType(found);
1.17 - }
1.18 -
1.19 - Type typeError(DiagnosticPosition pos, String problem, Type found, Type req, Object explanation) {
1.20 - log.error(pos, "prob.found.req.1", problem, found, req, explanation);
1.21 - return types.createErrorType(found);
1.22 - }
1.23 -
1.24 /** Report an error that wrong type tag was found.
1.25 * @param pos Position to be used for error reporting.
1.26 * @param required An internationalized string describing the type tag
1.27 @@ -430,6 +413,86 @@
1.28 * Type Checking
1.29 **************************************************************************/
1.30
1.31 + /**
1.32 + * A check context is an object that can be used to perform compatibility
1.33 + * checks - depending on the check context, meaning of 'compatibility' might
1.34 + * vary significantly.
1.35 + */
1.36 + interface CheckContext {
1.37 + /**
1.38 + * Is type 'found' compatible with type 'req' in given context
1.39 + */
1.40 + boolean compatible(Type found, Type req, Warner warn);
1.41 + /**
1.42 + * Instantiate a ForAll type against a given target type 'req' in given context
1.43 + */
1.44 + Type rawInstantiatePoly(ForAll found, Type req, Warner warn);
1.45 + /**
1.46 + * Report a check error
1.47 + */
1.48 + void report(DiagnosticPosition pos, Type found, Type req, JCDiagnostic details);
1.49 + /**
1.50 + * Obtain a warner for this check context
1.51 + */
1.52 + public Warner checkWarner(DiagnosticPosition pos, Type found, Type req);
1.53 + }
1.54 +
1.55 + /**
1.56 + * This class represent a check context that is nested within another check
1.57 + * context - useful to check sub-expressions. The default behavior simply
1.58 + * redirects all method calls to the enclosing check context leveraging
1.59 + * the forwarding pattern.
1.60 + */
1.61 + static class NestedCheckContext implements CheckContext {
1.62 + CheckContext enclosingContext;
1.63 +
1.64 + NestedCheckContext(CheckContext enclosingContext) {
1.65 + this.enclosingContext = enclosingContext;
1.66 + }
1.67 +
1.68 + public boolean compatible(Type found, Type req, Warner warn) {
1.69 + return enclosingContext.compatible(found, req, warn);
1.70 + }
1.71 +
1.72 + public Type rawInstantiatePoly(ForAll found, Type req, Warner warn) {
1.73 + return enclosingContext.rawInstantiatePoly(found, req, warn);
1.74 + }
1.75 +
1.76 + public void report(DiagnosticPosition pos, Type found, Type req, JCDiagnostic details) {
1.77 + enclosingContext.report(pos, found, req, details);
1.78 + }
1.79 +
1.80 + public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
1.81 + return enclosingContext.checkWarner(pos, found, req);
1.82 + }
1.83 + }
1.84 +
1.85 + /**
1.86 + * Check context to be used when evaluating assignment/return statements
1.87 + */
1.88 + CheckContext basicHandler = new CheckContext() {
1.89 + public void report(DiagnosticPosition pos, Type found, Type req, JCDiagnostic details) {
1.90 + if (details == null) {
1.91 + log.error(pos, "prob.found.req", found, req);
1.92 + } else {
1.93 + log.error(pos, "prob.found.req.1", details);
1.94 + }
1.95 + }
1.96 + public boolean compatible(Type found, Type req, Warner warn) {
1.97 + return types.isAssignable(found, req, warn);
1.98 + }
1.99 +
1.100 + public Type rawInstantiatePoly(ForAll found, Type req, Warner warn) {
1.101 + if (req.tag == NONE)
1.102 + req = found.qtype.tag <= VOID ? found.qtype : syms.objectType;
1.103 + return infer.instantiateExpr(found, req, warn);
1.104 + }
1.105 +
1.106 + public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
1.107 + return convertWarner(pos, found, req);
1.108 + }
1.109 + };
1.110 +
1.111 /** Check that a given type is assignable to a given proto-type.
1.112 * If it is, return the type, otherwise return errType.
1.113 * @param pos Position to be used for error reporting.
1.114 @@ -437,64 +500,54 @@
1.115 * @param req The type that was required.
1.116 */
1.117 Type checkType(DiagnosticPosition pos, Type found, Type req) {
1.118 - return checkType(pos, found, req, "incompatible.types");
1.119 + return checkType(pos, found, req, basicHandler);
1.120 }
1.121
1.122 - Type checkType(DiagnosticPosition pos, Type found, Type req, String errKey) {
1.123 + Type checkType(final DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) {
1.124 if (req.tag == ERROR)
1.125 return req;
1.126 - if (found.tag == FORALL)
1.127 - return instantiatePoly(pos, (ForAll)found, req, convertWarner(pos, found, req));
1.128 + if (found.tag == FORALL) {
1.129 + ForAll fa = (ForAll)found;
1.130 + Type owntype = instantiatePoly(pos, checkContext, fa, req, checkContext.checkWarner(pos, found, req));
1.131 + return checkType(pos, owntype, req, checkContext);
1.132 + }
1.133 if (req.tag == NONE)
1.134 return found;
1.135 - if (types.isAssignable(found, req, convertWarner(pos, found, req)))
1.136 + if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) {
1.137 return found;
1.138 - if (found.tag <= DOUBLE && req.tag <= DOUBLE)
1.139 - return typeError(pos, diags.fragment("possible.loss.of.precision"), found, req);
1.140 - if (found.isSuperBound()) {
1.141 - log.error(pos, "assignment.from.super-bound", found);
1.142 + } else {
1.143 + if (found.tag <= DOUBLE && req.tag <= DOUBLE) {
1.144 + checkContext.report(pos, found, req, diags.fragment("possible.loss.of.precision"));
1.145 + return types.createErrorType(found);
1.146 + }
1.147 + checkContext.report(pos, found, req, null);
1.148 return types.createErrorType(found);
1.149 }
1.150 - if (req.isExtendsBound()) {
1.151 - log.error(pos, "assignment.to.extends-bound", req);
1.152 - return types.createErrorType(found);
1.153 - }
1.154 - return typeError(pos, diags.fragment(errKey), found, req);
1.155 }
1.156
1.157 /** Instantiate polymorphic type to some prototype, unless
1.158 * prototype is `anyPoly' in which case polymorphic type
1.159 * is returned unchanged.
1.160 */
1.161 - Type instantiatePoly(DiagnosticPosition pos, ForAll t, Type pt, Warner warn) throws Infer.NoInstanceException {
1.162 - if (pt == Infer.anyPoly && complexInference) {
1.163 - return t;
1.164 - } else if (pt == Infer.anyPoly || pt.tag == NONE) {
1.165 - Type newpt = t.qtype.tag <= VOID ? t.qtype : syms.objectType;
1.166 - return instantiatePoly(pos, t, newpt, warn);
1.167 - } else if (pt.tag == ERROR) {
1.168 - return pt;
1.169 - } else {
1.170 - try {
1.171 - return infer.instantiateExpr(t, pt, warn);
1.172 - } catch (Infer.NoInstanceException ex) {
1.173 + Type instantiatePoly(DiagnosticPosition pos, CheckContext checkContext, ForAll t, Type pt, Warner warn) throws Infer.NoInstanceException {
1.174 + try {
1.175 + return checkContext.rawInstantiatePoly(t, pt, warn);
1.176 + } catch (final Infer.NoInstanceException ex) {
1.177 + JCDiagnostic d = ex.getDiagnostic();
1.178 + if (d != null) {
1.179 if (ex.isAmbiguous) {
1.180 - JCDiagnostic d = ex.getDiagnostic();
1.181 - log.error(pos,
1.182 - "undetermined.type" + (d!=null ? ".1" : ""),
1.183 - t, d);
1.184 - return types.createErrorType(pt);
1.185 - } else {
1.186 - JCDiagnostic d = ex.getDiagnostic();
1.187 - return typeError(pos,
1.188 - diags.fragment("incompatible.types" + (d!=null ? ".1" : ""), d),
1.189 - t, pt);
1.190 + d = diags.fragment("undetermined.type", t, d);
1.191 }
1.192 - } catch (Infer.InvalidInstanceException ex) {
1.193 - JCDiagnostic d = ex.getDiagnostic();
1.194 - log.error(pos, "invalid.inferred.types", t.tvars, d);
1.195 - return types.createErrorType(pt);
1.196 }
1.197 + checkContext.report(pos, t, pt, d);
1.198 + return types.createErrorType(pt);
1.199 + } catch (Infer.InvalidInstanceException ex) {
1.200 + JCDiagnostic d = ex.getDiagnostic();
1.201 + if (d != null) {
1.202 + d = diags.fragment("invalid.inferred.types", t.tvars, d);
1.203 + }
1.204 + checkContext.report(pos, t, pt, d);
1.205 + return types.createErrorType(pt);
1.206 }
1.207 }
1.208
1.209 @@ -505,15 +558,17 @@
1.210 * @param req The target type of the cast.
1.211 */
1.212 Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
1.213 + return checkCastable(pos, found, req, basicHandler);
1.214 + }
1.215 + Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) {
1.216 if (found.tag == FORALL) {
1.217 - instantiatePoly(pos, (ForAll) found, req, castWarner(pos, found, req));
1.218 + instantiatePoly(pos, basicHandler, (ForAll) found, req, castWarner(pos, found, req));
1.219 return req;
1.220 } else if (types.isCastable(found, req, castWarner(pos, found, req))) {
1.221 return req;
1.222 } else {
1.223 - return typeError(pos,
1.224 - diags.fragment("inconvertible.types"),
1.225 - found, req);
1.226 + checkContext.report(pos, found, req, diags.fragment("inconvertible.types", found, req));
1.227 + return types.createErrorType(found);
1.228 }
1.229 }
1.230
1.231 @@ -867,14 +922,6 @@
1.232 && types.isSubtype(actual, types.supertype(formal))
1.233 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
1.234 return;
1.235 -
1.236 - if (false) {
1.237 - // TODO: make assertConvertible work
1.238 - typeError(tree.pos(), diags.fragment("incompatible.types"), actual, formal);
1.239 - throw new AssertionError("Tree: " + tree
1.240 - + " actual:" + actual
1.241 - + " formal: " + formal);
1.242 - }
1.243 }
1.244
1.245 /**
