javax.lang.model.element.TypeParameterElement#asType ( )源码实例Demo

private DeclaredType getDeclaredType(TypeElement e, HashMap<? extends Element, ? extends TypeMirror> map, Types types) {
    List<? extends TypeParameterElement> tpes = e.getTypeParameters();
    TypeMirror[] targs = new TypeMirror[tpes.size()];
    int i = 0;
    for (Iterator<? extends TypeParameterElement> it = tpes.iterator(); it.hasNext();) {
        TypeParameterElement tpe = it.next();
        TypeMirror t = map.get(tpe);
        targs[i++] = t != null ? t : tpe.asType();
    }
    Element encl = e.getEnclosingElement();
    if ((encl.getKind().isClass() || encl.getKind().isInterface()) && !((TypeElement)encl).getTypeParameters().isEmpty())
            return types.getDeclaredType(getDeclaredType((TypeElement)encl, map, types), e, targs);
    return types.getDeclaredType(e, targs);
}
 

private DeclaredType getDeclaredType(TypeElement e, HashMap<? extends Element, ? extends TypeMirror> map, Types types) {
    List<? extends TypeParameterElement> tpes = e.getTypeParameters();
    TypeMirror[] targs = new TypeMirror[tpes.size()];
    int i = 0;
    for (Iterator<? extends TypeParameterElement> it = tpes.iterator(); it.hasNext();) {
        TypeParameterElement tpe = it.next();
        TypeMirror t = map.get(tpe);
        targs[i++] = t != null ? t : tpe.asType();
    }
    Element encl = e.getEnclosingElement();
    if ((encl.getKind().isClass() || encl.getKind().isInterface()) && !((TypeElement)encl).getTypeParameters().isEmpty())
            return types.getDeclaredType(getDeclaredType((TypeElement)encl, map, types), e, targs);
    return types.getDeclaredType(e, targs);
}
 

/**
 * Returns a new method spec builder that overrides {@code method}.
 *
 * <p>This will copy its visibility modifiers, type parameters, return type, name, parameters, and
 * throws declarations. An {@link Override} annotation will be added.
 *
 * <p>Note that in JavaPoet 1.2 through 1.7 this method retained annotations from the method and
 * parameters of the overridden method. Since JavaPoet 1.8 annotations must be added separately.
 */
public static Builder overriding(ExecutableElement method) {
  checkNotNull(method, "method == null");

  Set<Modifier> modifiers = method.getModifiers();
  if (modifiers.contains(Modifier.PRIVATE)
      || modifiers.contains(Modifier.FINAL)
      || modifiers.contains(Modifier.STATIC)) {
    throw new IllegalArgumentException("cannot override method with modifiers: " + modifiers);
  }

  String methodName = method.getSimpleName().toString();
  MethodSpec.Builder methodBuilder = MethodSpec.methodBuilder(methodName);

  methodBuilder.addAnnotation(Override.class);

  modifiers = new LinkedHashSet<>(modifiers);
  modifiers.remove(Modifier.ABSTRACT);
  modifiers.remove(Util.DEFAULT); // LinkedHashSet permits null as element for Java 7
  methodBuilder.addModifiers(modifiers);

  for (TypeParameterElement typeParameterElement : method.getTypeParameters()) {
    TypeVariable var = (TypeVariable) typeParameterElement.asType();
    methodBuilder.addTypeVariable(TypeVariableName.get(var));
  }

  methodBuilder.returns(TypeName.get(method.getReturnType()));
  methodBuilder.addParameters(ParameterSpec.parametersOf(method));
  methodBuilder.varargs(method.isVarArgs());

  for (TypeMirror thrownType : method.getThrownTypes()) {
    methodBuilder.addException(TypeName.get(thrownType));
  }

  return methodBuilder;
}
 

/**
 * Returns a new method spec builder that overrides {@code method}.
 *
 * <p>This will copy its visibility modifiers, type parameters, return type, name, parameters, and
 * throws declarations. An {@link Override} annotation will be added.
 *
 * <p>Note that in JavaPoet 1.2 through 1.7 this method retained annotations from the method and
 * parameters of the overridden method. Since JavaPoet 1.8 annotations must be added separately.
 */
public static Builder overriding(ExecutableElement method) {
  checkNotNull(method, "method == null");

  Set<Modifier> modifiers = method.getModifiers();
  if (modifiers.contains(Modifier.PRIVATE)
      || modifiers.contains(Modifier.FINAL)
      || modifiers.contains(Modifier.STATIC)) {
    throw new IllegalArgumentException("cannot override method with modifiers: " + modifiers);
  }

  String methodName = method.getSimpleName().toString();
  MethodSpec.Builder methodBuilder = MethodSpec.methodBuilder(methodName);

  methodBuilder.addAnnotation(Override.class);

  modifiers = new LinkedHashSet<>(modifiers);
  modifiers.remove(Modifier.ABSTRACT);
  modifiers.remove(Util.DEFAULT); // LinkedHashSet permits null as element for Java 7
  methodBuilder.addModifiers(modifiers);

  for (TypeParameterElement typeParameterElement : method.getTypeParameters()) {
    TypeVariable var = (TypeVariable) typeParameterElement.asType();
    methodBuilder.addTypeVariable(TypeVariableName.get(var));
  }

  methodBuilder.returns(TypeName.get(method.getReturnType()));
  methodBuilder.addParameters(ParameterSpec.parametersOf(method));
  methodBuilder.varargs(method.isVarArgs());

  for (TypeMirror thrownType : method.getThrownTypes()) {
    methodBuilder.addException(TypeName.get(thrownType));
  }

  return methodBuilder;
}
 

@Test
public void testAsElement() throws IOException {
  compile("class Foo<T> { }");

  TypeParameterElement tElement = elements.getTypeElement("Foo").getTypeParameters().get(0);
  TypeVariable tVar = (TypeVariable) tElement.asType();

  assertSame(tElement, tVar.asElement());
}
 

protected TypeMirror getTypeParameterUpperBound(String typeName, int typeParameterIndex) {
  TypeParameterElement typeParameter =
      elements.getTypeElement(typeName).getTypeParameters().get(typeParameterIndex);
  TypeVariable typeVariable = (TypeVariable) typeParameter.asType();

  return typeVariable.getUpperBound();
}
 

/**
 * Returns a new method spec builder that overrides {@code method}.
 *
 * <p>This will copy its visibility modifiers, type parameters, return type, name, parameters, and
 * throws declarations. An {@link Override} annotation will be added.
 *
 * <p>Note that in JavaPoet 1.2 through 1.7 this method retained annotations from the method and
 * parameters of the overridden method. Since JavaPoet 1.8 annotations must be added separately.
 */
public static Builder overriding(ExecutableElement method) {
  checkNotNull(method, "method == null");

  Element enclosingClass = method.getEnclosingElement();
  if (enclosingClass.getModifiers().contains(Modifier.FINAL)) {
    throw new IllegalArgumentException("Cannot override method on final class " + enclosingClass);
  }

  Set<Modifier> modifiers = method.getModifiers();
  if (modifiers.contains(Modifier.PRIVATE)
      || modifiers.contains(Modifier.FINAL)
      || modifiers.contains(Modifier.STATIC)) {
    throw new IllegalArgumentException("cannot override method with modifiers: " + modifiers);
  }

  String methodName = method.getSimpleName().toString();
  MethodSpec.Builder methodBuilder = MethodSpec.methodBuilder(methodName);

  methodBuilder.addAnnotation(Override.class);

  modifiers = new LinkedHashSet<>(modifiers);
  modifiers.remove(Modifier.ABSTRACT);
  modifiers.remove(Modifier.DEFAULT);
  methodBuilder.addModifiers(modifiers);

  for (TypeParameterElement typeParameterElement : method.getTypeParameters()) {
    TypeVariable var = (TypeVariable) typeParameterElement.asType();
    methodBuilder.addTypeVariable(TypeVariableName.get(var));
  }

  methodBuilder.returns(TypeName.get(method.getReturnType()));
  methodBuilder.addParameters(ParameterSpec.parametersOf(method));
  methodBuilder.varargs(method.isVarArgs());

  for (TypeMirror thrownType : method.getThrownTypes()) {
    methodBuilder.addException(TypeName.get(thrownType));
  }

  return methodBuilder;
}