in freemarker-core/src/main/java/freemarker/ext/beans/BeansWrapper.java [1183:1404]
private Object tryUnwrapTo(final TemplateModel model, Class<?> targetClass, final int typeFlags,
final Map<Object, Object> recursionStops)
throws TemplateModelException {
if (model == null || model == nullModel) {
return null;
}
final boolean is2321Bugfixed = is2321Bugfixed();
if (is2321Bugfixed && targetClass.isPrimitive()) {
targetClass = ClassUtil.primitiveClassToBoxingClass(targetClass);
}
// This is for transparent interop with other wrappers (and ourselves)
// Passing the targetClass allows i.e. a Jython-aware method that declares a
// PyObject as its argument to receive a PyObject from a JythonModel
// passed as an argument to TemplateMethodModelEx etc.
if (model instanceof AdapterTemplateModel) {
Object wrapped = ((AdapterTemplateModel) model).getAdaptedObject(
targetClass);
if (targetClass == Object.class || targetClass.isInstance(wrapped)) {
return wrapped;
}
// Attempt numeric conversion:
if (targetClass != Object.class && (wrapped instanceof Number && ClassUtil.isNumerical(targetClass))) {
Number number = forceUnwrappedNumberToType((Number) wrapped, targetClass, is2321Bugfixed);
if (number != null) return number;
}
}
if (model instanceof WrapperTemplateModel) {
Object wrapped = ((WrapperTemplateModel) model).getWrappedObject();
if (targetClass == Object.class || targetClass.isInstance(wrapped)) {
return wrapped;
}
// Attempt numeric conversion:
if (targetClass != Object.class && (wrapped instanceof Number && ClassUtil.isNumerical(targetClass))) {
Number number = forceUnwrappedNumberToType((Number) wrapped, targetClass, is2321Bugfixed);
if (number != null) {
return number;
}
}
}
// Translation of generic template models to POJOs. First give priority
// to various model interfaces based on the targetClass. This helps us
// select the appropriate interface in multi-interface models when we
// know what is expected as the return type.
if (targetClass != Object.class) {
// [2.4][IcI]: Should also check for CharSequence at the end
if (String.class == targetClass) {
if (model instanceof TemplateScalarModel) {
return ((TemplateScalarModel) model).getAsString();
}
// String is final, so no other conversion will work
return ObjectWrapperAndUnwrapper.CANT_UNWRAP_TO_TARGET_CLASS;
}
// Primitive numeric types & Number.class and its subclasses
if (ClassUtil.isNumerical(targetClass)) {
if (model instanceof TemplateNumberModel) {
Number number = forceUnwrappedNumberToType(
((TemplateNumberModel) model).getAsNumber(), targetClass, is2321Bugfixed);
if (number != null) {
return number;
}
}
}
if (boolean.class == targetClass || Boolean.class == targetClass) {
if (model instanceof TemplateBooleanModel) {
return Boolean.valueOf(((TemplateBooleanModel) model).getAsBoolean());
}
// Boolean is final, no other conversion will work
return ObjectWrapperAndUnwrapper.CANT_UNWRAP_TO_TARGET_CLASS;
}
if (Map.class == targetClass) {
if (model instanceof TemplateHashModel) {
return new HashAdapter((TemplateHashModel) model, this);
}
}
if (List.class == targetClass) {
if (model instanceof TemplateSequenceModel) {
return new SequenceAdapter((TemplateSequenceModel) model, this);
}
}
if (Set.class == targetClass) {
if (model instanceof TemplateCollectionModel) {
return new SetAdapter((TemplateCollectionModel) model, this);
}
}
if (Collection.class == targetClass || Iterable.class == targetClass) {
if (model instanceof TemplateCollectionModel) {
return new CollectionAdapter((TemplateCollectionModel) model,
this);
}
if (model instanceof TemplateSequenceModel) {
return new SequenceAdapter((TemplateSequenceModel) model, this);
}
}
// TemplateSequenceModels can be converted to arrays
if (targetClass.isArray()) {
if (model instanceof TemplateSequenceModel) {
return unwrapSequenceToArray((TemplateSequenceModel) model, targetClass, true, recursionStops);
}
// array classes are final, no other conversion will work
return ObjectWrapperAndUnwrapper.CANT_UNWRAP_TO_TARGET_CLASS;
}
// Allow one-char strings to be coerced to characters
if (char.class == targetClass || targetClass == Character.class) {
if (model instanceof TemplateScalarModel) {
String s = ((TemplateScalarModel) model).getAsString();
if (s.length() == 1) {
return Character.valueOf(s.charAt(0));
}
}
// Character is final, no other conversion will work
return ObjectWrapperAndUnwrapper.CANT_UNWRAP_TO_TARGET_CLASS;
}
if (Date.class.isAssignableFrom(targetClass) && model instanceof TemplateDateModel) {
Date date = ((TemplateDateModel) model).getAsDate();
if (targetClass.isInstance(date)) {
return date;
}
}
} // End: if (targetClass != Object.class)
// Since the targetClass was of no help initially, now we use
// a quite arbitrary order in which we walk through the TemplateModel subinterfaces, and unwrapp them to
// their "natural" Java correspondent. We still try exclude unwrappings that won't fit the target parameter
// type(s). This is mostly important because of multi-typed FTL values that could be unwrapped on multiple ways.
int itf = typeFlags; // Iteration's Type Flags. Should be always 0 for non-overloaded and when !is2321Bugfixed.
// If itf != 0, we possibly execute the following loop body at twice: once with utilizing itf, and if it has not
// returned, once more with itf == 0. Otherwise we execute this once with itf == 0.
do {
if ((itf == 0 || (itf & TypeFlags.ACCEPTS_NUMBER) != 0)
&& model instanceof TemplateNumberModel) {
Number number = ((TemplateNumberModel) model).getAsNumber();
if (itf != 0 || targetClass.isInstance(number)) {
return number;
}
}
if ((itf == 0 || (itf & TypeFlags.ACCEPTS_DATE) != 0)
&& model instanceof TemplateDateModel) {
Date date = ((TemplateDateModel) model).getAsDate();
if (itf != 0 || targetClass.isInstance(date)) {
return date;
}
}
if ((itf == 0 || (itf & (TypeFlags.ACCEPTS_STRING | TypeFlags.CHARACTER)) != 0)
&& model instanceof TemplateScalarModel
&& (itf != 0 || targetClass.isAssignableFrom(String.class))) {
String strVal = ((TemplateScalarModel) model).getAsString();
if (itf == 0 || (itf & TypeFlags.CHARACTER) == 0) {
return strVal;
} else { // TypeFlags.CHAR == 1
if (strVal.length() == 1) {
if ((itf & TypeFlags.ACCEPTS_STRING) != 0) {
return new CharacterOrString(strVal);
} else {
return Character.valueOf(strVal.charAt(0));
}
} else if ((itf & TypeFlags.ACCEPTS_STRING) != 0) {
return strVal;
}
// It had to be unwrapped to Character, but the string length wasn't 1 => Fall through
}
}
// Should be earlier than TemplateScalarModel, but we keep it here until FM 2.4 or such
if ((itf == 0 || (itf & TypeFlags.ACCEPTS_BOOLEAN) != 0)
&& model instanceof TemplateBooleanModel
&& (itf != 0 || targetClass.isAssignableFrom(Boolean.class))) {
return Boolean.valueOf(((TemplateBooleanModel) model).getAsBoolean());
}
if ((itf == 0 || (itf & TypeFlags.ACCEPTS_MAP) != 0)
&& model instanceof TemplateHashModel
&& (itf != 0 || targetClass.isAssignableFrom(HashAdapter.class))) {
return new HashAdapter((TemplateHashModel) model, this);
}
if ((itf == 0 || (itf & TypeFlags.ACCEPTS_LIST) != 0)
&& model instanceof TemplateSequenceModel
&& (itf != 0 || targetClass.isAssignableFrom(SequenceAdapter.class))) {
return new SequenceAdapter((TemplateSequenceModel) model, this);
}
if ((itf == 0 || (itf & TypeFlags.ACCEPTS_SET) != 0)
&& model instanceof TemplateCollectionModel
&& (itf != 0 || targetClass.isAssignableFrom(SetAdapter.class))) {
return new SetAdapter((TemplateCollectionModel) model, this);
}
// In 2.3.21 bugfixed mode only, List-s are convertible to arrays on invocation time. Only overloaded
// methods need this. As itf will be 0 in non-bugfixed mode and for non-overloaded method calls, it's
// enough to check if the TypeFlags.ACCEPTS_ARRAY bit is 1:
if ((itf & TypeFlags.ACCEPTS_ARRAY) != 0
&& model instanceof TemplateSequenceModel) {
return new SequenceAdapter((TemplateSequenceModel) model, this);
}
if (itf == 0) {
break;
}
itf = 0; // start 2nd iteration
} while (true);
// Last ditch effort - is maybe the model itself is an instance of the required type?
// Note that this will be always true for Object.class targetClass.
if (targetClass.isInstance(model)) {
return model;
}
return ObjectWrapperAndUnwrapper.CANT_UNWRAP_TO_TARGET_CLASS;
}