Type Checking - Introduction to Compiler Construction in a Java World - page 136

((JTypeDecl)
typeDeclaration).preAnalyze(context);
}
}
4.4.3 JClassDeclaration.preAnalyze()
In a class declaration, preAnalyze() does the following:
1. It rst creates a new ClassContext , whose surroundingContext points to the
CompilationUnitContext .
2. It resolves the class's super type.
3. It creates a new CLEmitter instance, which will eventually be converted to the Class
object for representing the declared class.
4. It adds a class header, defining a name and any modifiers, to this CLEmitter instance.
5. It recursively invokes preAnalyze() on each of the class' members. This causes eld
declarations, constructors, and method declarations (but with empty bodies) to be
added to the CLEmitter instance.
6. If there is no explicit constructor (having no arguments) in the set of members, it adds
the implicit constructor to the CLEmitter instance. For example, for the Factorial
program above, the following implicit constructor is added, even though it is never
used in the Factorial program:
publicFactorial(){
super.Factorial();
}
7. Finally, the CLEmitter instance produces a Class object, and that replaces the
classRep for the Type of the declared class name in the (parent) ClassContext .
Notice that this pass need not descend into method bodies. If j--, like full Java, supported
nested classes, then preAnalyze() would have to examine all of the statements of every
method body to see if it were a nested class needing pre-analysis.
The code for JClassDeclaration 's preAnalyze() is as follows:
publicvoidpreAnalyze(Contextcontext){
//Constructaclasscontext
this.context=newClassContext(this,context);
//Resolvesuperclass
superType=superType.resolve(this.context);
//Creatingapartialclassinmemorycanresultina
//java.lang.VerifyErrorifthesemanticsbeloware
//violated,sowecan'tdeferthesecheckstoanalyze()
thisType.checkAccess(line,superType);
if(superType.isFinal()){
JAST.compilationUnit.reportSemanticError(line,
"Cannotextendafinaltype:%s",
superType.toString());
}
//Createthe(partial)class