Source code: org/bluej/core/DataElement.java

   package    org.bluej.core;
   
   public  class  DataElement {
     public  static  final  int  NULL    = 0x00;
     public  static  final  int  U_INT_1    = 0x08;
     public  static  final  int  U_INT_2    = 0x09;
     public  static  final  int  U_INT_4    = 0x0a;
     public  static  final  int  U_INT_8    = 0x0b;
     public  static  final  int  U_INT_16  = 0x0c;
    public  static  final  int  INT_1    = 0x10;
    public  static  final  int  INT_2    = 0x11;
    public  static  final  int  INT_4    = 0x12;
    public  static  final  int  INT_8    = 0x13;
    public  static  final  int  INT_16    = 0x14;
    public  static  final  int  URL      = 0x40;
    public  static  final  int  UUID    = 0x18;
    public  static  final  int  BOOL    = 0x28;
    public  static  final  int  STRING    = 0x20;
    public  static  final  int  DATSEQ    = 0x30;
    public  static  final  int  DATALT    = 0x38;
  
    int    type;
    Object  val;
  
    class  List {
      DataElement  elt;
      List    next;
      List(DataElement elem) {
        elt = elem;
      }
    }
    public   class  ListScanner implements java.util.Enumeration {
      List  scan;
      ListScanner(List val) {
        scan = (List)val;
      }
      public  boolean  hasMoreElements() {
        return !(scan == null);
      }
      public  Object  nextElement() {
        Object  ret = scan.elt;
        scan = scan.next;
        return ret;
      }
    }
  
    public  DataElement(int valueType) {
      type = valueType;
      switch (valueType) {
      case NULL:    case DATALT:  case DATSEQ:
        val = null;
        break;
      default:
        throw new IllegalArgumentException(
              "only NULL, DATALT or DATSEQ allowed");
      }
    }
    public  DataElement(boolean bool) {
      type = BOOL;
      val = new Boolean(bool);
    }
    public  DataElement(int valueType, long value) {
      type = valueType;
      switch (valueType) {
      case U_INT_1:  case U_INT_2:  case U_INT_4:
      case INT_1:    case INT_2:    case INT_4:    case  INT_8:
        val = new Long(value);
        break;
      default:
        throw new IllegalArgumentException(
          "only integers (except U_INT_8) allowed");
      }
    }
    public  DataElement(int valueType, Object value) {
      boolean  ok = false;
      type = valueType;
      val = value;
      switch (valueType) {
      case URL:  case STRING:
        if (val instanceof String)
          ok = true;
        break;
      case UUID:
        if (val instanceof UUID)
          ok = true;
        break;
      case INT_16:  case U_INT_8:  case U_INT_16:
        if (val instanceof byte[]) {
          byte[]  vec = (byte[])val;
          if (vec.length == (valueType == U_INT_8 ? 8 : 16))
            ok = true;
        }
        break;
      }
      if (!ok)
        throw new IllegalArgumentException( "incorrect argument");
    }
  
    public  void  addElement(DataElement elem) {
     if (type != DATSEQ && type != DATALT)
       throw new ClassCastException("incorrect argument");
     if (elem == null)
       throw new NullPointerException("null in addElement");
     List  elt = new List(elem);
     if (val == null) {
       val = elt;
     }
     else {
       List  last = (List)val;
       List  next = last.next;
       while (next != null) {
         last = next;
         next = last.next;
       }
       last.next = elt;
     }
   }
 
   public  int    getSize() {
     if (type != DATSEQ && type != DATALT)
       throw new ClassCastException("incorrect argument");
     int    size = 0;
     List  scan = (List)val;
     while (scan != null) {
       size++;
       scan = scan.next;
     }
     return size;
   }
 
   public  void  insertElementAt(DataElement elem, int index) {
     if (type != DATSEQ && type != DATALT)
       throw new ClassCastException("incorrect argument");
     if (elem == null)
       throw new NullPointerException("null in addElement");
     if (index < 0 || index > getSize())
       throw new IndexOutOfBoundsException("bad index " + index);
     List  elt = new List(elem);
     if (index == 0) {
       elt.next = (List)val;
       val = elt;
     }
     else {
       List  last = null;
       List  scan = (List)val;
       for (int i = 0; i < index-1; i++) {
         last = scan;
         scan = scan.next;
       }
       if (last == null) {
         elt.next = (List)val;
         val = elt;
       }
       else {
         elt.next = last.next;
         last.next = elt;
       }
     }
   }
   public  boolean  removeElement(DataElement elem) {
     if (type != DATSEQ && type != DATALT)
       throw new ClassCastException("incorrect argument");
     if (elem == null)
       throw new NullPointerException("null in addElement");
     List  last = null;
     List  scan = (List)val;
     while (scan != null) {
       if (scan.elt == elem) {
         if (last == null)
           val = scan;
         else
           last.next = scan.next;
         return true;
       }
       last = scan;
       scan = scan.next;
     }
     return false;
   }
 
   public  int    getDataType() {
     return type;
   }
 
   public  long  getLong() {
     Long  l = (Long)val;
     return l.longValue();
   }
   public  boolean  getBoolean() {
     Boolean  b = (Boolean)val;
     return b.booleanValue();
   }
   public  Object  getValue() {
     Object    ret;
     switch (type) {
     case DATALT:  case DATSEQ:
       ret = new ListScanner((List)val);
       break;
     case INT_16:  case U_INT_8:  case U_INT_16:
     case URL:    case UUID:    case STRING:
       ret = val;
       break;
     default:
       throw new ClassCastException("cannot be an integer");
     }
     return ret;
   }
 }