C++ Handle::Int32Value方法代码示例

int32_t toInt32(v8::Handle<v8::Value> value, IntegerConversionConfiguration configuration, ExceptionState& exceptionState)
{
    // Fast case. The value is already a 32-bit integer.
    if (value->IsInt32())
        return value->Int32Value();

    // Can the value be converted to a number?
    V8TRYCATCH_EXCEPTION_RETURN(v8::Local<v8::Number>, numberObject, value->ToNumber(), exceptionState, 0);
    if (numberObject.IsEmpty()) {
        exceptionState.throwTypeError("Not convertible to a number value (of type 'long'.)");
        return 0;
    }

    if (configuration == EnforceRange)
        return enforceRange(numberObject->Value(), kMinInt32, kMaxInt32, "long", exceptionState);

    // Does the value convert to nan or to an infinity?
    double numberValue = numberObject->Value();
    if (std::isnan(numberValue) || std::isinf(numberValue))
        return 0;

    if (configuration == Clamp)
        return clampTo<int32_t>(numberObject->Value());

    V8TRYCATCH_EXCEPTION_RETURN(int32_t, result, numberObject->Int32Value(), exceptionState, 0);
    return result;
}

String v8NonStringValueToWebCoreString(v8::Handle<v8::Value> object)
{
    ASSERT(!object->IsString());
    if (object->IsInt32()) {
        int value = object->Int32Value();
        // Most numbers used are <= 100. Even if they aren't used there's very little in using the space.
        const int kLowNumbers = 100;
        static AtomicString lowNumbers[kLowNumbers + 1];
        String webCoreString;
        if (0 <= value && value <= kLowNumbers) {
            webCoreString = lowNumbers[value];
            if (!webCoreString) {
                AtomicString valueString = AtomicString(String::number(value));
                lowNumbers[value] = valueString;
                webCoreString = valueString;
            }
        } else
            webCoreString = String::number(value);
        return webCoreString;
    }

    v8::TryCatch block;
    v8::Handle<v8::String> v8String = object->ToString();
    // Handle the case where an exception is thrown as part of invoking toString on the object.
    if (block.HasCaught()) {
        throwError(block.Exception());
        return StringImpl::empty();
    }
    return v8StringToWebCoreString<String>(v8String, DoNotExternalize);
}

uint8_t toUInt8(v8::Handle<v8::Value> value, IntegerConversionConfiguration configuration, bool& ok)
{
    ok = true;

    // Fast case. The value is a 32-bit signed integer - possibly positive?
    if (value->IsInt32()) {
        int32_t result = value->Int32Value();
        if (result >= 0 && result <= kMaxUInt8)
            return static_cast<uint8_t>(result);
        if (configuration == EnforceRange) {
            ok = false;
            return 0;
        }
        // Converting to uint8_t will cause the resulting value to be the value modulo 2^8.
        return static_cast<uint8_t>(result);
    }

    // Can the value be converted to a number?
    v8::Local<v8::Number> numberObject = value->ToNumber();
    if (numberObject.IsEmpty()) {
        ok = false;
        return 0;
    }

    if (configuration == EnforceRange)
        return enforceRange(numberObject->Value(), 0, kMaxUInt8, ok);

    // Does the value convert to nan or to an infinity?
    double numberValue = numberObject->Value();
    if (std::isnan(numberValue) || std::isinf(numberValue) || !numberValue)
        return 0;

    numberValue = numberValue < 0 ? -floor(abs(numberValue)) : floor(abs(numberValue));
    return static_cast<uint8_t>(fmod(numberValue, 256)); // 2^8.
}

std::string jsHistory::go(v8::Handle<v8::Value> pos)
{
    string retval = "";

    if (pos->IsInt32()) {
        // process offset
        int offs = pos->Int32Value();
        offs += index;
        if (offs > 0 && offs < (int)history.size()) {
            index = offs;
            retval = history[index];
            if (window != NULL) {
                window->load(retval);
            }
        }
    } else if (pos->IsString()) {
        // search for substring
        string srch = value_to_string(Local<Value>::New(pos));
        for( size_t i = 0 ; i < history.size(); ++i) {
            if (history[i].find(srch) != string::npos) {
                index = i;
                retval = history[index];
                if (window != NULL) {
                    window->load(retval);
                }
                break;
            }
        }
    }

    return retval;
}

int toInt32(v8::Handle<v8::Value> value, bool& ok)
{
    ok = true;
    
    // Fast case. The value is already a 32-bit integer.
    if (value->IsInt32())
        return value->Int32Value();
    
    // Can the value be converted to a number?
    v8::Local<v8::Number> numberObject = value->ToNumber();
    if (numberObject.IsEmpty()) {
        ok = false;
        return 0;
    }
    
    // Does the value convert to nan or to an infinity?
    double numberValue = numberObject->Value();
    if (isnan(numberValue) || isinf(numberValue)) {
        ok = false;
        return 0;
    }
    
    // Can the value be converted to a 32-bit integer?
    v8::Local<v8::Int32> intValue = value->ToInt32();
    if (intValue.IsEmpty()) {
        ok = false;
        return 0;
    }
    
    // Return the result of the int32 conversion.
    return intValue->Value();
}

int64_t toInt64(v8::Handle<v8::Value> value, IntegerConversionConfiguration configuration, bool& ok)
{
    ok = true;

    // Fast case. The value is a 32-bit integer.
    if (value->IsInt32())
        return value->Int32Value();

    // Can the value be converted to a number?
    v8::Local<v8::Number> numberObject = value->ToNumber();
    if (numberObject.IsEmpty()) {
        ok = false;
        return 0;
    }

    double x = numberObject->Value();

    if (configuration == EnforceRange)
        return enforceRange(x, -kJSMaxInteger, kJSMaxInteger, ok);

    // NaNs and +/-Infinity should be 0, otherwise modulo 2^64.
    unsigned long long integer;
    doubleToInteger(x, integer);
    return integer;
}

PassRefPtr<IDBKey> createIDBKeyFromValue(v8::Handle<v8::Value> value)
{
    if (value->IsNull())
        return IDBKey::create();
    if (value->IsInt32())
        return IDBKey::create(value->Int32Value());
    if (value->IsString())
        return IDBKey::create(v8ValueToWebCoreString(value));
    // FIXME: Implement dates.
    return 0;
}

String v8NonStringValueToWebCoreString(v8::Handle<v8::Value> object)
{
    ASSERT(!object->IsString());
    if (object->IsInt32())
        return int32ToWebCoreString(object->Int32Value());

    v8::TryCatch block;
    v8::Handle<v8::String> v8String = object->ToString();
    // Handle the case where an exception is thrown as part of invoking toString on the object.
    if (block.HasCaught()) {
        throwError(block.Exception());
        return StringImpl::empty();
    }
    return v8StringToWebCoreString<String>(v8String, DoNotExternalize);
}

uint32_t toUInt32(v8::Handle<v8::Value> value, bool& ok)
{
    ok = true;

    // FIXME: there is currently no Value::IsUint32(). This code does
    // some contortions to avoid silently converting out-of-range
    // values to uint32_t.

    // Fast case.  The value is already a 32-bit positive integer.
    if (value->IsInt32()) {
        int32_t result = value->Int32Value();
        if (result >= 0)
            return result;
    }

    // Can the value be converted to a number?
    v8::Local<v8::Number> numberObject = value->ToNumber();
    if (numberObject.IsEmpty()) {
        ok = false;
        return 0;
    }

    // Does the value convert to nan or to an infinity?
    double numberValue = numberObject->Value();
    if (isnan(numberValue) || isinf(numberValue)) {
        ok = false;
        return 0;
    }

    // Can the value be converted to a 32-bit unsigned integer?
    v8::Local<v8::Uint32> uintValue = value->ToUint32();
    if (uintValue.IsEmpty()) {
        ok = false;
        return 0;
    }

    // FIXME: v8::Uint32::Value is not defined!
    // http://code.google.com/p/v8/issues/detail?id=624
    v8::Local<v8::Int32> intValue = value->ToInt32();
    if (intValue.IsEmpty()) {
        ok = false;
        return 0;
    }

    return static_cast<uint32_t>(intValue->Value());
}

jobject wrapJSObject(JNIEnv *pEnv, v8::Handle<v8::Value> value)
{
  v8::HandleScope handle_scope;

  if (value.IsEmpty() || value->IsNull() || value->IsUndefined()) return NULL;
  if (value->IsTrue()) return NewBoolean(pEnv, JNI_TRUE);
  if (value->IsFalse()) return NewBoolean(pEnv, JNI_FALSE);

  if (value->IsInt32()) return NewInt(pEnv, value->Int32Value());
  if (value->IsUint32()) return NewLong(pEnv, value->IntegerValue());
  if (value->IsString()) return NewString(pEnv, v8::Handle<v8::String>::Cast(value));
  if (value->IsDate()) return NewDate(pEnv, v8::Handle<v8::Date>::Cast(value));
  if (value->IsNumber()) return NewDouble(pEnv, value->NumberValue());

//  return wrap(value->ToObject());
  return NULL;
}

static Value v8ValueToValue(v8::Handle<v8::Value> v8Value)
{
    v8::HandleScope scope;
    if (v8Value->IsArray()) {
        List<Value> value;
        const v8::Handle<v8::Array> v8Array = v8::Handle<v8::Array>::Cast(v8Value);
        const uint32_t size = v8Array->Length();
        for (uint32_t i = 0; i < size; ++i) {
            if (v8Array->Has(i))
                value.append(v8ValueToValue(v8Array->Get(i)));
            else
                value.append(Value());
        }
        return Value(value);
    } else if (v8Value->IsObject()) {
        Map<String, Value> value;
        const v8::Handle<v8::Object> v8Object = v8Value->ToObject();
        const v8::Handle<v8::Array> props = v8Object->GetPropertyNames();
        const uint32_t size = props->Length();
        for (uint32_t i = 0; i < size; ++i) {
            assert(props->Has(i));
            const v8::Handle<v8::Value> name = props->Get(i);
            value[String(*v8::String::Utf8Value(name))] = v8ValueToValue(v8Object->Get(name));
        }
        return Value(value);
    } else if (v8Value->IsBoolean()) {
        return Value(v8Value->BooleanValue());
    } else if (v8Value->IsInt32() || v8Value->IsUint32()) {
        return Value(v8Value->Int32Value());
    } else if (v8Value->IsNumber()) {
        return Value(v8Value->NumberValue());
    } else if (v8Value->IsString()) {
        return Value(String(*v8::String::Utf8Value(v8Value)));
    } else {
        error() << "Unexpected v8 value type in JSONParser";
    }
    // undefined or null?
    return Value();
}

static String v8NonStringValueToWebCoreString(v8::Handle<v8::Value> object)
{
    ASSERT(!object->IsString());
    if (object->IsInt32())
        return int32ToWebCoreString(object->Int32Value());

    v8::TryCatch block;
    v8::Handle<v8::String> v8String = object->ToString();
    // Handle the case where an exception is thrown as part of invoking toString on the object.
    if (block.HasCaught()) {
        throwError(block.Exception());
        return StringImpl::empty();
    }
    // This path is unexpected. However there is hypothesis that it
    // might be combination of v8 and v8 bindings bugs. For now
    // just bailout as we'll crash if attempt to convert empty handle into a string.
    if (v8String.IsEmpty()) {
        ASSERT_NOT_REACHED();
        return StringImpl::empty();
    }
    return v8StringToWebCoreString<String>(v8String, DoNotExternalize);
}

uint32_t toUInt32(v8::Handle<v8::Value> value, bool& ok)
{
    ok = true;

    // Fast case. The value is already a 32-bit unsigned integer.
    if (value->IsUint32())
        return value->Uint32Value();

    if (value->IsInt32()) {
        int32_t result = value->Int32Value();
        if (result >= 0)
            return result;
    }

    // Can the value be converted to a number?
    v8::Local<v8::Number> numberObject = value->ToNumber();
    if (numberObject.IsEmpty()) {
        ok = false;
        return 0;
    }

    // Does the value convert to nan or to an infinity?
    double numberValue = numberObject->Value();
    if (isnan(numberValue) || isinf(numberValue)) {
        ok = false;
        return 0;
    }

    // Can the value be converted to a 32-bit unsigned integer?
    v8::Local<v8::Uint32> uintValue = value->ToUint32();
    if (uintValue.IsEmpty()) {
        ok = false;
        return 0;
    }

    return uintValue->Value();
}

inline int32_t Int(v8::Handle<v8::Value> hdl) {
  return hdl->Int32Value();
}

 static int32_t apply(v8::Handle<v8::Value> const& value)
 {
     return value->Int32Value();
 }