Using MPXJ Library in Java

If you want to read a Microsoft Project Plan (MPP) file in Java then you can use the MPXJ library to manipulate data of the MPP file. Using this library you can also create a new MPP file. For more information you can refer to my Article on the MPXJ Library.

To use this library you can use the following procedure:

1. Add a reference of MPXJ.jar
2. Import the following namespaces:
   
   import net.sf.mpxj;
   import net.sf.mpxj.reader;
   import net.sf.mpxj.writer;
   import net.sf.mpxj.mpp;
    
3. Create an object of the ProjectReader and ProjectFile classes, as in:
   
   ProjectReader reader = new MPPReader();
   ProjectFile projectObj = reader.read();
   
   • Tasks
      

     for (Task task : project.getAllTasks())

     {

        System.out.println("Task: " + task.getName() + " ID=" + task.getID() + " Unique ID=" + task.getUniqueID());

     }

      

   •  Resources
     
      

     for (Resource resource : project.getAllResources())

     {

       System.out.println("Resource: " + resource.getName() + " (Unique ID=" + resource.getUniqueID() + ")");

     }
      

   • SubTasks
     
      List tasks = project.getChildTasks();
                 Task task = tasks.get(0);
                 tasks = task.getChildTasks();
      
   • Access Resource and Task  by ID
     
      Resource r = project.getResourceByUniqueID(Integer.valueOf(99));
     Task t = project.getTaskByUniqueID(Integer.valueOf(99));
      
   • Calendar
     
     ProjectCalendar defaultCalendar = projectObj.getCalendar();         
     ProjectCalendar taskCalendar = task.getCalendar();
      
   • Predecessor relationships between tasks
     
           

     for (Task task : file.getAllTasks())

     {    List predecessors = task.getPredecessors();

           if (predecessors != null && predecessors.isEmpty() == false)

            {

                 System.out.println(task.getName() + " predecessors:");

                for (Relation relation : predecessors)

                {

                 System.out.println("   Task: " +  file.getTaskByUniqueID(relation.getTaskUniqueID()).getName());

                 System.out.println("   Type: " + relation.getType());

                 System.out.println("   Lag: " + relation.getDuration());

                }       

              }

       }
      

4. Now if we want to access tasks, subtasks, calendars or resources from a MPP file then we need to use the methods using a ProjectFile Object.
5. There are many methods provided by MPXJ library you can use depending on your requirements.
6. Now if you want to create a MPP file then use the following:
   
   
   •  Create Source ProjectFile Object
     
     ProjectReader reader = new MPPReader();
     ProjectFile sourceObj = reader.read();
      
   • Create object of projectWriter class
     
     ProjectWriter writer = ProjectWriterUtility.getProjectWriter();
      writer.write(sourceObj, );

Reference(s)

http://mpxj.sourceforge.net/