Package com.google.common.reflect

Class TypeVisitor

  • Direct Known Subclasses:
    TypeResolver.TypeMappingIntrospector
    abstract class TypeVisitor
extends java.lang.Object
    Based on what a Type is, dispatch it to the corresponding visit* method. By default, no recursion is done for type arguments or type bounds. But subclasses can opt to do recursion by calling visit(java.lang.reflect.Type...) for any Type while visitation is in progress. For example, this can be used to reject wildcards or type variables contained in a type as in: 
    
 new TypeVisitor() {
   protected void visitParameterizedType(ParameterizedType t) {
     visit(t.getOwnerType());
     visit(t.getActualTypeArguments());
   }
   protected void visitGenericArrayType(GenericArrayType t) {
     visit(t.getGenericComponentType());
   }
   protected void visitTypeVariable(TypeVariable<?> t) {
     throw new IllegalArgumentException("Cannot contain type variable.");
   }
   protected void visitWildcardType(WildcardType t) {
     throw new IllegalArgumentException("Cannot contain wildcard type.");
   }
 }.visit(type);

    One Type is visited at most once. The second time the same type is visited, it's ignored by visit(java.lang.reflect.Type...). This avoids infinite recursion caused by recursive type bounds.

    This class is not thread safe.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      private java.util.Set<java.lang.reflect.Type> visited  

    • Constructor Summary

      Constructors 
      Constructor Description
      TypeVisitor()  

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void visit​(java.lang.reflect.Type... types)
      Visits the given types.
      (package private) void visitClass​(java.lang.Class<?> t)  
      (package private) void visitGenericArrayType​(java.lang.reflect.GenericArrayType t)  
      (package private) void visitParameterizedType​(java.lang.reflect.ParameterizedType t)  
      (package private) void visitTypeVariable​(java.lang.reflect.TypeVariable<?> t)  
      (package private) void visitWildcardType​(java.lang.reflect.WildcardType t)  

      • Methods inherited from class java.lang.Object

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

    • Field Detail

      • visited

        private final java.util.Set<java.lang.reflect.Type> visited

    • Constructor Detail

      • TypeVisitor

        TypeVisitor()

    • Method Detail

      • visit

        public final void visit​(java.lang.reflect.Type... types)
        Visits the given types. Null types are ignored. This allows subclasses to call visit(parameterizedType.getOwnerType()) safely without having to check nulls.

      • visitClass

        void visitClass​(java.lang.Class<?> t)

      • visitGenericArrayType

        void visitGenericArrayType​(java.lang.reflect.GenericArrayType t)

      • visitParameterizedType

        void visitParameterizedType​(java.lang.reflect.ParameterizedType t)

      • visitTypeVariable

        void visitTypeVariable​(java.lang.reflect.TypeVariable<?> t)

      • visitWildcardType

        void visitWildcardType​(java.lang.reflect.WildcardType t)