org.stringtemplate.v4.misc.MapModelAdaptor Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of ST4 Show documentation

StringTemplate is a java template engine for generating source code, web pages, emails, or any other formatted text output. StringTemplate is particularly good at multi-targeted code generators, multiple site skins, and internationalization/localization. It evolved over years of effort developing jGuru.com. StringTemplate also powers the ANTLR 3 and 4 code generator. Its distinguishing characteristic is that unlike other engines, it strictly enforces model-view separation. Strict separation makes websites and code generators more flexible and maintainable; it also provides an excellent defense against malicious template authors.

There is a newer version: 4.3.4

Show newest version

/*
 * [The "BSD license"]
 *  Copyright (c) 2011 Terence Parr
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *  3. The name of the author may not be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 *  IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 *  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 *  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.stringtemplate.v4.misc;

import org.stringtemplate.v4.Interpreter;
import org.stringtemplate.v4.ModelAdaptor;
import org.stringtemplate.v4.ST;
import org.stringtemplate.v4.STGroup;

import java.util.Map;

public class MapModelAdaptor implements ModelAdaptor> {
    @Override
    public Object getProperty(Interpreter interp, ST self, Map model, Object property, String propertyName)
        throws STNoSuchPropertyException
    {
        Object value;
        if ( property==null ) value = getDefaultValue(model);
        else if ( containsKey(model, property) ) value = model.get(property);
        else if ( containsKey(model, propertyName) ) { // if can't find the key, try toString version
            value = model.get(propertyName);
        }
        else if ( property.equals("keys") ) value = model.keySet();
        else if ( property.equals("values") ) value = model.values();
        else value = getDefaultValue(model); // not found, use default
        if ( value == STGroup.DICT_KEY ) {
            value = property;
        }
        return value;
    }

    private static Boolean containsKey(Map map, Object key) {
        try {
            return map.containsKey(key);
        }
        catch (ClassCastException ex) {
            // Map.containsKey is allowed to throw ClassCastException if the key
            // cannot be compared to keys already in the map.
            return false;
        }
    }

    private static Object getDefaultValue(Map map) {
        try {
            return map.get(STGroup.DEFAULT_KEY);
        }
        catch (ClassCastException ex) {
            // Map.containsKey is allowed to throw ClassCastException if the key
            // cannot be compared to keys already in the map.
            return false;
        }
    }
}