JythonVersionAdapter.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package freemarker.ext.jython;

import org.python.core.PyObject;

/**
 * Functions that has a different implementation depending on the Jython version
 * used. This was introduced to work around class-loading errors because of
 * different classes/methods being present in different Jython versions.
 */
public abstract class JythonVersionAdapter {

    /**
     * Returns
     * <code>obj instanceof Py[Java]Instance</code>. 
     */
    public abstract boolean isPyInstance(Object obj);
    
    /**
     * Returns
     * <code>((PyInstance) py[Java]Instance).__tojava__(java.lang.Object.class)</code>.
     */
    public abstract Object pyInstanceToJava(Object pyInstance);
    
    /**
     * Returns <code>pyObject.__class__.__name__</code> 
     */
    public abstract String getPythonClassName(PyObject pyObject);
    
}