jythonwrapper.java

freemaker安装软件

        {
            return modelCache.getInstance(obj, JythonNumberModel.FACTORY);
        }
        if(obj instanceof PyNone) {
            return null;
        }
        return modelCache.getInstance(obj, JythonModel.FACTORY);
    }
    
    /**
     * Coerces a template model into a {@link PyObject}.
     * @param model the model to coerce
     * @return the coerced model.
     * <ul>
     * <li>
     * <li>{@link AdapterTemplateModel}s (i.e. {@link freemarker.ext.beans.BeanModel}) are marshalled
     *   using the standard Python marshaller {@link Py#java2py(Object)} on 
     *   the result of <code>getWrappedObject(PyObject.class)</code>s. The 
     *   native JythonModel instances will just return the underlying PyObject. 
     * <li>All other models that are {@link TemplateScalarModel scalars} are 
     *   marshalled as {@link PyString}.
     * <li>All other models that are {@link TemplateNumberModel numbers} are 
     *   marshalled using the standard Python marshaller
     *   {@link Py#java2py(Object)} on their underlying <code>Number</code></li>
     * <li>All other models  are marshalled to a generic internal 
     *   <code>PyObject</code> subclass that'll correctly pass
     *   <code>__finditem__</code>, <code>__len__</code>,
     *   <code>__nonzero__</code>, and <code>__call__</code> invocations to 
     *   appropriate hash, sequence, and method models.</li>
     * </ul>
     */
    public PyObject unwrap(TemplateModel model) throws TemplateModelException
    {
        if(model instanceof AdapterTemplateModel) {
            return Py.java2py(((AdapterTemplateModel)model).getAdaptedObject(
                    PYOBJECT_CLASS));
        }
        if(model instanceof WrapperTemplateModel) {
            return Py.java2py(((WrapperTemplateModel)model).getWrappedObject());
        }

        // Scalars are marshalled to PyString.
        if(model instanceof TemplateScalarModel)
        {
            return new PyString(((TemplateScalarModel)model).getAsString());
        }
        
        // Numbers are wrapped to Python built-in numeric types.
        if(model instanceof TemplateNumberModel)
        {
            Number number = ((TemplateNumberModel)model).getAsNumber();
            if(number instanceof BigDecimal)
            {
                number = OptimizerUtil.optimizeNumberRepresentation(number);
            }
            if(number instanceof BigInteger)
            {
                // Py.java2py can't automatically coerce a BigInteger into
                // a PyLong. This will probably get fixed in later Jython
                // release.
                return new PyLong((BigInteger)number);
            }
            else
            {
                return Py.java2py(number);
            }
        }
        // Return generic TemplateModel-to-Python adapter
        return new TemplateModelToJythonAdapter(model);
    }

    private class TemplateModelToJythonAdapter extends PyObject 
    implements TemplateModelAdapter 
    {
        private final TemplateModel model;
        
        TemplateModelToJythonAdapter(TemplateModel model)
        {
            this.model = model;
        }
        
        public TemplateModel getTemplateModel()
        {
            return model;
        }
        
        public PyObject __finditem__(PyObject key)
        {
            if(key instanceof PyInteger)
            {
                return __finditem__(((PyInteger)key).getValue());
            }
            return __finditem__(key.toString());
        }

        public PyObject __finditem__(String key)
        {
            if(model instanceof TemplateHashModel)
            {
                try
                {
                    return unwrap(((TemplateHashModel)model).get(key));
                }
                catch(TemplateModelException e)
                {
                    throw Py.JavaError(e);
                }
            }
            throw Py.TypeError("item lookup on non-hash model (" + getModelClass() + ")");
        }
        
        public PyObject __finditem__(int index)
        {
            if(model instanceof TemplateSequenceModel)
            {
                try
                {
                    return unwrap(((TemplateSequenceModel)model).get(index));
                }
                catch(TemplateModelException e)
                {
                    throw Py.JavaError(e);
                }
            }
            throw Py.TypeError("item lookup on non-sequence model (" + getModelClass() + ")");
        }
        
        public PyObject __call__(PyObject args[], String keywords[])
        {
            if(model instanceof TemplateMethodModel)
            {
                boolean isEx = model instanceof TemplateMethodModelEx;
                List list = new ArrayList(args.length);
                try
                {
                    for(int i = 0; i < args.length; ++i)
                    {
                        list.add(
                            isEx 
                            ? (Object)wrap(args[i]) 
                            : (Object)(
                                args[i] == null 
                                ? null 
                                : args[i].toString()));
                    }
                    return unwrap((TemplateModel) ((TemplateMethodModelEx)model).exec(list));
                }
                catch(TemplateModelException e)
                {
                    throw Py.JavaError(e);
                }
            }
            throw Py.TypeError("call of non-method model (" + getModelClass() + ")");
        }
        
        public int __len__()
        {
            try
            {
                if(model instanceof TemplateSequenceModel)
                {
                    return ((TemplateSequenceModel)model).size();
                }
                if(model instanceof TemplateHashModelEx)
                {
                    return ((TemplateHashModelEx)model).size();
                }
            }
            catch(TemplateModelException e)
            {
                throw Py.JavaError(e);
            }
            
            return 0;
        }
        
        public boolean __nonzero__()
        {
            try
            {
                if(model instanceof TemplateBooleanModel)
                {
                    return ((TemplateBooleanModel)model).getAsBoolean();
                }
                if(model instanceof TemplateSequenceModel)
                {
                    return ((TemplateSequenceModel)model).size() > 0;
                }
                if(model instanceof TemplateHashModel)
                {
                    return !((TemplateHashModelEx)model).isEmpty();
                }
            }
            catch(TemplateModelException e)
            {
                throw Py.JavaError(e);
            }
            return false;
        }
        
        private String getModelClass()
        {
            return model == null ? "null" : model.getClass().getName();
        }
    }
}