content: /*****************************************************************
   *   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
   *
   *    https://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 org.apache.cayenne.ejbql.parser;
  
  import org.apache.cayenne.ejbql.EJBQLBaseVisitor;
  import org.apache.cayenne.ejbql.EJBQLExpression;
  import org.apache.cayenne.ejbql.EJBQLExpressionVisitor;
  
  /**
   * @since 3.0
   */
  public class EJBQLFromItem extends SimpleNode {
  
      public EJBQLFromItem(int id) {
          super(id);
      }
  
      /**
       * Returns an id generated from the entity name. It is used when no user-specified id
       * exists.
       */
      public String getSyntheticId() {
          int len = getChildrenCount();
          if (len < 1) {
              return null;
          }
  
          final String[] entityNames = new String[1];
          getChild(0).visit(new EJBQLBaseVisitor() {
  
              @Override
              public boolean visitIdentificationVariable(EJBQLExpression expression) {
                  entityNames[0] = expression.getText();
                  return false;
              }
          });
          
          if (entityNames[0] == null) {
              return null;
          }
  
          // id's are case insensitive, while entity names are. Using simple encoding to
          // transform the entity name in such way that two entities that differ only in
          // capitalization would produce different lowercase ids
  
          StringBuilder id = new StringBuilder(entityNames[0].length() + 2);
          for (int i = 0; i < entityNames[0].length(); i++) {
              char c = entityNames[0].charAt(i);
              if (Character.isUpperCase(c)) {
                  id.append('%').append(Character.toLowerCase(c));
              }
              else {
                  id.append(c);
              }
          }
  
          return id.toString();
  
      }
  
      public String getId() {
          int len = getChildrenCount();
          if (len < 2) {
              return getSyntheticId();
          }
  
          return jjtGetChild(len - 1).getText();
      }
  
      @Override
      protected boolean visitNode(EJBQLExpressionVisitor visitor) {
          return visitor.visitFromItem(this, -1);
      }
  
      @Override
      protected boolean visitChild(EJBQLExpressionVisitor visitor, int childIndex) {
          return super.visitChild(visitor, childIndex)
                  && visitor.visitFromItem(this, childIndex);
      }
  }
  