reportbuilder/java/org/libreoffice/report/pentaho/DefaultNameGenerator.java

   1 /*
   2  * This file is part of the LibreOffice project.
   3  *
   4  * This Source Code Form is subject to the terms of the Mozilla Public
   5  * License, v. 2.0. If a copy of the MPL was not distributed with this
   6  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   7  *
   8  * This file incorporates work covered by the following license notice:
   9  *
  10  *   Licensed to the Apache Software Foundation (ASF) under one or more
  11  *   contributor license agreements. See the NOTICE file distributed
  12  *   with this work for additional information regarding copyright
  13  *   ownership. The ASF licenses this file to you under the Apache
  14  *   License, Version 2.0 (the "License"); you may not use this file
  15  *   except in compliance with the License. You may obtain a copy of
  16  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  17  */
  18 package org.libreoffice.report.pentaho;
  19
  20 import org.libreoffice.report.OutputRepository;
  21
  22 import java.io.IOException;
  23
  24
  25 public class DefaultNameGenerator
  26 {
  27
  28     private final OutputRepository outputRepository;
  29
  30     public DefaultNameGenerator(final OutputRepository outputRepository)
  31     {
  32         if (outputRepository == null)
  33         {
  34             throw new NullPointerException();
  35         }
  36         this.outputRepository = outputRepository;
  37     }
  38
  39     public String generateName(final String namePrefix, final String mimeType)
  40             throws IOException
  41     {
  42         return generateName(namePrefix, mimeType, true);
  43     }
  44
  45     public String generateStorageName(final String namePrefix, final String mimeType)
  46             throws IOException
  47     {
  48         return generateName(namePrefix, mimeType, false);
  49     }
  50
  51     /**
  52      * Generates a new, unique name for storing resources in the output repository. Assuming that proper synchronization
  53      * has been applied, the generated name will be unique within that repository.
  54      *
  55      * @param namePrefix a user defined name for that resource.
  56      * @param mimeType   the mime type of the resource to be stored in the repository.
  57      * @param isStream
  58      * @return the generated, fully qualified name.
  59      * @throws java.io.IOException
  60      */
  61     private String generateName(final String namePrefix, final String mimeType, final boolean isStream)
  62             throws IOException
  63     {
  64         final String name;
  65         if (namePrefix != null)
  66         {
  67             name = namePrefix;
  68         }
  69         else
  70         {
  71             name = "file";
  72         }
  73
  74         StringBuffer firstFileName = new StringBuffer();
  75         firstFileName.append(name);
  76         final String suffix;
  77         if (mimeType != null)
  78         {
  79             suffix = getSuffixForType(mimeType);
  80             firstFileName.append('.');
  81             firstFileName.append(suffix);
  82         }
  83         else
  84         {
  85             suffix = null;
  86         }
  87         String newName = firstFileName.toString();
  88         boolean exists;
  89         if (isStream)
  90         {
  91             exists = outputRepository.exists(newName);
  92         }
  93         else
  94         {
  95             exists = outputRepository.existsStorage(newName);
  96         }
  97         if (exists)
  98         {
  99             int counter = 0;
 100             while (exists)
 101             {
 102                 if (counter < 0) // wraparound should not happen...
 103                 {
 104                     throw new IOException();
 105                 }
 106                 firstFileName.delete(0, firstFileName.length());
 107                 firstFileName.append(name);
 108                 firstFileName.append(counter);
 109                 if (suffix != null)
 110                 {
 111                     firstFileName.append('.');
 112                     firstFileName.append(suffix);
 113                 }
 114                 newName = firstFileName.toString();
 115                 if (isStream)
 116                 {
 117                     exists = outputRepository.exists(newName);
 118                 }
 119                 else
 120                 {
 121                     exists = outputRepository.existsStorage(newName);
 122                 }
 123                 counter++;
 124             }
 125         }
 126         return newName;
 127     }
 128
 129     private String getSuffixForType(final String mimeType)
 130     {
 131         if ("image/png".equals(mimeType))
 132         {
 133             return "png";
 134         }
 135         if ("image/jpeg".equals(mimeType))
 136         {
 137             return "jpg";
 138         }
 139         if ("image/gif".equals(mimeType))
 140         {
 141             return "gif";
 142         }
 143
 144         // todo ... use a flexible mapping ...
 145         return "dat";
 146     }
 147 }