JavaArgumentConverters.java 文件源码

@SuppressWarnings("unused")
private static Number toNumber(final Object obj0) {
    // TODO - Order tests for performance.
    for (Object obj = obj0; ;) {
        if (obj == null) {
            return null;
        } else if (obj instanceof Number) {
            return (Number) obj;
        } else if (obj instanceof String) {
            return JSType.toNumber((String) obj);
        } else if (obj instanceof ConsString) {
            return JSType.toNumber(obj.toString());
        } else if (obj instanceof Boolean) {
            return (Boolean) obj ? 1 : +0.0;
        } else if (obj instanceof ScriptObject) {
            obj = JSType.toPrimitive(obj, Number.class);
            continue;
        } else if (obj == UNDEFINED) {
            return Double.NaN;
        }
        throw assertUnexpectedType(obj);
    }
}