| 1 | package uk.co.zonetora.fj.model; |
| 2 | |
| 3 | import static uk.co.zonetora.fj.util.ListUtil.mapFst; |
| 4 | import static uk.co.zonetora.fj.util.ListUtil.mapSnd; |
| 5 | |
| 6 | import java.util.ArrayList; |
| 7 | import java.util.Collection; |
| 8 | import java.util.HashSet; |
| 9 | import java.util.List; |
| 10 | import java.util.Set; |
| 11 | |
| 12 | import uk.co.zonetora.fj.passes.FJException; |
| 13 | import uk.co.zonetora.fj.typecheck.ClassTable; |
| 14 | import uk.co.zonetora.fj.typecheck.TypeCheck; |
| 15 | import uk.co.zonetora.fj.typecheck.TypeEnvironment; |
| 16 | import uk.co.zonetora.fj.util.Arrow; |
| 17 | import uk.co.zonetora.fj.util.Tuple; |
| 18 | |
| 19 | public class Method { |
| 20 | |
| 21 | private static final ArgumentName thisArgName = new ArgumentName("this"); |
| 22 | |
| 23 | public static ArgumentName getThisArgName() { |
| 24 | return thisArgName; |
| 25 | } |
| 26 | |
| 27 | private final ClassName returnType; |
| 28 | private final MethodName methodName; |
| 29 | private final List<Tuple<ClassName, ArgumentName>> arguments; |
| 30 | private final Term code; |
| 31 | |
| 32 | public Method(ClassName returnType, MethodName methodName, Term code) { |
| 33 | this.returnType = returnType; |
| 34 | this.methodName = methodName; |
| 35 | this.code = code; |
| 36 | this.arguments = new ArrayList<Tuple<ClassName,ArgumentName>>(); |
| 37 | } |
| 38 | |
| 39 | public void addArgument(ClassName cn, ArgumentName an) { |
| 40 | this.arguments.add(new Tuple<ClassName, ArgumentName>(cn,an)); |
| 41 | } |
| 42 | |
| 43 | public Set<ClassName> getAllReferencedClassNames() { |
| 44 | Set<ClassName> allReferencedClassNames = new HashSet<ClassName>(); |
| 45 | allReferencedClassNames.add(this.returnType); |
| 46 | |
| 47 | for(Tuple<ClassName, ArgumentName> arg : this.arguments) { |
| 48 | allReferencedClassNames.add(arg.getX()); |
| 49 | } |
| 50 | |
| 51 | allReferencedClassNames.addAll(this.code.getAllReferencedClassNames()); |
| 52 | |
| 53 | return allReferencedClassNames; |
| 54 | } |
| 55 | |
| 56 | public List<FJException> checkMOk(ClassDecl decl, ClassTable c) { |
| 57 | final List<FJException> exceptions = new ArrayList<FJException>(); |
| 58 | |
| 59 | exceptions.addAll(sanityCheckArguments()); |
| 60 | if(exceptions.isEmpty()) { |
| 61 | c.mType(this.methodName, decl.getSuperClass()).maybe( |
| 62 | null, |
| 63 | new Arrow<Method, Object>() { |
| 64 | public Object run(Method arg) { |
| 65 | exceptions.addAll(checkMethodOverridesCorrectly(arg)); |
| 66 | return null; |
| 67 | } |
| 68 | } |
| 69 | ); |
| 70 | |
| 71 | } |
| 72 | |
| 73 | if(exceptions.isEmpty()) { |
| 74 | exceptions.addAll(typeCheckCode(decl.getClassName(), c)); |
| 75 | } |
| 76 | |
| 77 | return exceptions; |
| 78 | } |
| 79 | |
| 80 | private Collection< ? extends FJException> typeCheckCode(ClassName thisClassName, ClassTable ct) { |
| 81 | List<FJException> exceptions = new ArrayList<FJException>(); |
| 82 | |
| 83 | TypeEnvironment te = new TypeEnvironment(); |
| 84 | te.addBinding(Method.thisArgName, thisClassName); |
| 85 | |
| 86 | for(Tuple<ClassName, ArgumentName> arg : this.arguments) { |
| 87 | te.addBinding(arg.getY(), arg.getX()); |
| 88 | } |
| 89 | |
| 90 | try { |
| 91 | ClassName codeType = new TypeCheck(te, ct).typeCheck(this.code); |
| 92 | |
| 93 | if(!ct.subtype(codeType, this.returnType)) { |
| 94 | exceptions.add(new FJException("Method return type is not a supertype of the code type")); |
| 95 | } |
| 96 | } catch (FJException e) { |
| 97 | exceptions.add(e); |
| 98 | } |
| 99 | |
| 100 | return exceptions; |
| 101 | } |
| 102 | |
| 103 | private Collection< ? extends FJException> sanityCheckArguments() { |
| 104 | List<FJException> exceptions = new ArrayList<FJException>(); |
| 105 | Set<ArgumentName> args = new HashSet<ArgumentName>(mapSnd(this.arguments)); |
| 106 | if(args.size() != this.arguments.size()) { |
| 107 | exceptions.add(new FJException("Duplicate argument name in method")); |
| 108 | } |
| 109 | |
| 110 | if(args.contains(Method.thisArgName)) { |
| 111 | exceptions.add(new FJException("this as an argument name in method")); |
| 112 | } |
| 113 | |
| 114 | return exceptions; |
| 115 | } |
| 116 | |
| 117 | public Object getName() { |
| 118 | return this.methodName; |
| 119 | } |
| 120 | |
| 121 | private Collection< ? extends FJException> checkMethodOverridesCorrectly(Method superClassVersion) { |
| 122 | List<FJException> exceptions = new ArrayList<FJException>(); |
| 123 | |
| 124 | if(!mapFst(superClassVersion.arguments).equals(mapFst(this.arguments))) { |
| 125 | exceptions.add(new FJException("Method does not override argumets correctly")); |
| 126 | } |
| 127 | |
| 128 | if(!this.returnType.equals(superClassVersion.returnType)) { |
| 129 | exceptions.add(new FJException("Method does not override return type correctly")); |
| 130 | } |
| 131 | |
| 132 | return exceptions; |
| 133 | } |
| 134 | |
| 135 | public List<Tuple<ClassName, ArgumentName>> getArguments() { |
| 136 | return new ArrayList<Tuple<ClassName, ArgumentName>>(this.arguments); |
| 137 | } |
| 138 | |
| 139 | public ClassName getReturnType() { |
| 140 | return this.returnType; |
| 141 | } |
| 142 | |
| 143 | |
| 144 | } |