public Element asElement(TypeMirror t)
Returns the element corresponding to a type.
The type may be a {@code DeclaredType} or {@code TypeVariable}.
Returns {@code null} if the type is not one with a
corresponding element.

 public TypeMirror asMemberOf(DeclaredType containing,
    Element element)
Returns the type of an element when that element is viewed as
a member of, or otherwise directly contained by, a given type.
For example,
when viewed as a member of the parameterized type {@code Set},
the {@code Set.add} method is an {@code ExecutableType}
whose parameter is of type {@code String}.

 public TypeElement boxedClass(PrimitiveType p)
Returns the class of a boxed value of a given primitive type.
That is, boxing conversion is applied.

 public TypeMirror capture(TypeMirror t)
Applies capture conversion to a type.

 public boolean contains(TypeMirror t1,
    TypeMirror t2)
Tests whether one type argument contains another.

 public List<TypeMirror> directSupertypes(TypeMirror t)
Returns the direct supertypes of a type.  The interface types, if any,
will appear last in the list.

 public TypeMirror erasure(TypeMirror t)
Returns the erasure of a type.

 public ArrayType getArrayType(TypeMirror componentType)
Returns an array type with the specified component type.

 public DeclaredType getDeclaredType(TypeElement typeElem,
    TypeMirror typeArgs)
Returns the type corresponding to a type element and
actual type arguments.
Given the type element for {@code Set} and the type mirror
for {@code String},
for example, this method may be used to get the
parameterized type {@code Set}.

 The number of type arguments must either equal the
number of the type element's formal type parameters, or must be
zero.  If zero, and if the type element is generic,
then the type element's raw type is returned.

 If a parameterized type is being returned, its type element
must not be contained within a generic outer class.
The parameterized type {@code Outer.Inner},
for example, may be constructed by first using this
method to get the type {@code Outer}, and then invoking
#getDeclaredType(DeclaredType, TypeElement, TypeMirror...) .

 public DeclaredType getDeclaredType(DeclaredType containing,
    TypeElement typeElem,
    TypeMirror typeArgs)
Returns the type corresponding to a type element
and actual type arguments, given a
{@linkplain DeclaredType#getEnclosingType() containing type}
of which it is a member.
The parameterized type {@code Outer.Inner},
for example, may be constructed by first using
#getDeclaredType(TypeElement, TypeMirror...) 
to get the type {@code Outer}, and then invoking
this method.

 If the containing type is a parameterized type,
the number of type arguments must equal the
number of {@code typeElem}'s formal type parameters.
If it is not parameterized or if it is {@code null}, this method is
equivalent to {@code getDeclaredType(typeElem, typeArgs)}.

 public NoType getNoType(TypeKind kind)
Returns a pseudo-type used where no actual type is appropriate.
The kind of type to return may be either
 VOID  or  NONE .
For packages, use
Elements#getPackageElement(CharSequence) {@code .asType()}
instead.

 public NullType getNullType()
Returns the null type.  This is the type of {@code null}.

 public PrimitiveType getPrimitiveType(TypeKind kind)
Returns a primitive type.

 public WildcardType getWildcardType(TypeMirror extendsBound,
    TypeMirror superBound)
Returns a new wildcard type argument.  Either of the wildcard's
bounds may be specified, or neither, but not both.

 public boolean isAssignable(TypeMirror t1,
    TypeMirror t2)
Tests whether one type is assignable to another.

 public boolean isSameType(TypeMirror t1,
    TypeMirror t2)
Tests whether two {@code TypeMirror} objects represent the same type.

Caveat: if either of the arguments to this method represents a
wildcard, this method will return false.  As a consequence, a wildcard
is not the same type as itself.  This might be surprising at first,
but makes sense once you consider that an example like this must be
rejected by the compiler:
  {@code List list = new ArrayList

 public boolean isSubsignature(ExecutableType m1,
    ExecutableType m2)
Tests whether the signature of one method is a subsignature
of another.

 public boolean isSubtype(TypeMirror t1,
    TypeMirror t2)
Tests whether one type is a subtype of another.
Any type is considered to be a subtype of itself.

 public PrimitiveType unboxedType(TypeMirror t)
Returns the type (a primitive type) of unboxed values of a given type.
That is, unboxing conversion is applied.