FMHelper.java

/*
 * ******************************************************************************
 * MontiCore Language Workbench
 * Copyright (c) 2016, MontiCore, All rights reserved.
 *
 * This project is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3.0 of the License, or (at your option) any later version.
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this project. If not, see <http://www.gnu.org/licenses/>.
 * ******************************************************************************
 */
package freemarker.core;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import freemarker.template.Template;


/**
 * Helper class for Freemarker templates
 *
 * @author Jerome Pfeiffer
 */
public class FMHelper {
  
  /**
   * Finds all MethodCalls within dollarsigns in the passed template. Returns a
   * Map with the methodCallName as key an a list of list of arguments. Each
   * list contains arguments of a single methodCall.
   * 
   * @param t
   * @return methodCallName -> [param11, param12,...][param21, param22, ...]
   */
  public static Map<String, List<List<String>>> getMethodCalls(Template t) {
    Map<String, List<List<String>>> arguments = new HashMap<>();
    TemplateElement e = t.getRootTreeNode();
    if (e instanceof MixedContent) {
      MixedContent mc = (MixedContent) e;
      for (int i = 0; i < mc.getRegulatedChildCount(); i++) {
        TemplateElement child = mc.getRegulatedChild(i);
        if (child instanceof DollarVariable) {
          DollarVariable d = (DollarVariable) child;
          Object o = d.getParameterValue(0);
          if (o instanceof MethodCall) {
            MethodCall m = (MethodCall) o;
            String name = getMethodCallName(m);
            List<String> args = getMethodCallArguments(m);
            List<List<String>> tmp = new ArrayList<>();
            if (arguments.containsKey(name)) {
              tmp = arguments.get(name);
            }
            tmp.add(args);
            arguments.put(name, tmp);
          }
        }
      }
    }
    return arguments;
  }
  
  /**
   * Converts a list of parameter Strings to a List of Type Parameter
   * e.g. "Integer s" -> new Parameter(type, name)
   * 
   * @param params
   * @return
   */
  public static List<Parameter> getParams(List<String> params) {
    List<Parameter> ret = new ArrayList<>();
    for (String s : params) {
      s = s.replace("\"", "");
      String type = s.substring(0, s.indexOf(" "));
      type = type.trim();
      String name = s.substring(s.indexOf(" ") + 1);
      name = name.trim();
      Parameter a = new Parameter(type, name);
      ret.add(a);
    }
    return ret;
  }
  
  /**
   * Returns a name of MethodCall m as String
   * 
   * @param m
   * @return
   */
  private static String getMethodCallName(MethodCall m) {
    return ((Expression) m.getParameterValue(0)).toString();
  }
  
  /**
   * Returns the list of method arguments as String list.
   * 
   * @param m
   * @return
   */
  private static List<String> getMethodCallArguments(MethodCall m) {
    List<String> params = new ArrayList<>();
    for (int i = 1; i < m.getParameterCount(); i++) {
      params.add(((Expression) m.getParameterValue(i)).toString());
    }
    return params;
  }
}