| 1 | package dmg.cells.nucleus ; |
| 2 | import java.util.* ; |
| 3 | import java.io.* ; |
| 4 | /** |
| 5 | * |
| 6 | * The CellPath is an abstraction of the path a CellMessage is |
| 7 | * assumed to travel. The path consists of a defined sequence of |
| 8 | * cell hops and a current position. The last hop which might |
| 9 | * as well be the only one, is called the FinalDestination. |
| 10 | * At any point a new Cell Hop can be added in two ways : |
| 11 | * <ul> |
| 12 | * <li>At the end of the sequence. The added Cell becomes the |
| 13 | * new FinalDestination. |
| 14 | * <li>Insert the new Cell behind the current position. The new |
| 15 | * Hop becomes the next hop. |
| 16 | * </ul> |
| 17 | * The string representation of a cell path can have the format: |
| 18 | * <pre> |
| 19 | * path : <addr1>[:<<addr2>[...]] |
| 20 | * addr : <cellName> | <cellName@domainName> | <cellName@local> |
| 21 | * </pre> |
| 22 | * |
| 23 | * @author Patrick Fuhrmann |
| 24 | * @version 0.1, 15 Feb 1998 |
| 25 | */ |
| 26 | /* |
| 27 | */ |
| 28 | public class CellPath implements Cloneable , Serializable { |
| 29 | private static final long serialVersionUID = -4922955783102747577L; |
| 30 | |
| 31 | private List<CellAddressCore> _list = new ArrayList<CellAddressCore>() ; |
| 32 | private List<CellAddressCore> _mark = null ; |
| 33 | private int _position = -1 ; |
| 34 | private int _storage = -1 ; |
| 35 | |
| 36 | protected CellPath(){ /* only subclasses allowed to created 'empty' paths*/} |
| 37 | protected CellPath( CellPath addr ){ |
| 38 | // |
| 39 | // this only works because _list contains |
| 40 | // immutable objects |
| 41 | // |
| 42 | _list.addAll(addr._list); |
| 43 | _position = addr._position ; |
| 44 | _storage = addr._storage ; |
| 45 | } |
| 46 | /** |
| 47 | * Creates a CellAddress with an initial path of <path> |
| 48 | * |
| 49 | * @param path The initial cell travel path. |
| 50 | */ |
| 51 | public CellPath( String path ){ |
| 52 | add( path ) ; |
| 53 | } |
| 54 | public CellPath( String cellName , String domainName ){ |
| 55 | add( new CellAddressCore( cellName , domainName ) ) ; ; |
| 56 | } |
| 57 | public int hops(){ return _list.size() ; } |
| 58 | synchronized void add( CellAddressCore core ){ |
| 59 | _list.add( core ) ; |
| 60 | if( _position < 0 )_position = 0 ; |
| 61 | } |
| 62 | public synchronized void add( CellPath addr ){ |
| 63 | _list.addAll( addr._list ) ; |
| 64 | } |
| 65 | public void add( String cell , String domain ){ |
| 66 | add( new CellAddressCore( cell , domain ) ) ; |
| 67 | } |
| 68 | /** |
| 69 | * Adds a cell path <path> to the end of the current path. |
| 70 | * |
| 71 | * @param path The added cell travel path. |
| 72 | */ |
| 73 | public synchronized void add( String path ){ |
| 74 | StringTokenizer st = new StringTokenizer( path ,":" ) ; |
| 75 | for( ; st.hasMoreTokens() ; ){ |
| 76 | add( new CellAddressCore( st.nextToken() ) ) ; |
| 77 | } |
| 78 | } |
| 79 | /** |
| 80 | * Creates a CellAddress with a single cell as initial destination. |
| 81 | * The cell is represented by its name and the name of its domain. |
| 82 | * |
| 83 | * @param cellName The name of the initial destination cell. |
| 84 | * @param domainName The name of the initial destination cells domain. |
| 85 | */ |
| 86 | public Object clone(){ |
| 87 | CellPath addr = new CellPath() ; |
| 88 | addr._list.addAll(_list); |
| 89 | addr._position = _position ; |
| 90 | addr._storage = _storage ; |
| 91 | return addr ; |
| 92 | } |
| 93 | /** |
| 94 | * Adds a cell path <path> to the end of the current path. |
| 95 | * |
| 96 | * @param path The added cell travel path. |
| 97 | */ |
| 98 | synchronized void insert( CellAddressCore core ){ |
| 99 | _list.add(_position + 1, core) ; |
| 100 | if( _position < 0 )_position = 0 ; |
| 101 | } |
| 102 | public synchronized void insert( String path ){ |
| 103 | StringTokenizer st = new StringTokenizer( path ,":" ) ; |
| 104 | for( ; st.hasMoreTokens() ; ){ |
| 105 | insert( new CellAddressCore( st.nextToken() ) ) ; |
| 106 | } |
| 107 | } |
| 108 | public void mark(){ |
| 109 | _mark = new ArrayList<CellAddressCore>(_list) ; |
| 110 | _storage = _position ; |
| 111 | } |
| 112 | public void reset(){ |
| 113 | if( _mark == null )return ; |
| 114 | _list = _mark ; |
| 115 | _position = _storage ; |
| 116 | |
| 117 | _storage = -1; |
| 118 | _mark = null; |
| 119 | } |
| 120 | public void insert( String cell , String domain ){ |
| 121 | add( new CellAddressCore( cell , domain ) ) ; |
| 122 | } |
| 123 | /** |
| 124 | * Increment the current cell position by one. |
| 125 | * |
| 126 | * @return true if the cell hops could be shifted, false if |
| 127 | * current cell was the final destination. |
| 128 | */ |
| 129 | public synchronized boolean next(){ |
| 130 | if( _position >= ( _list.size() - 1 ) )return false ; |
| 131 | _position++ ; |
| 132 | return true; |
| 133 | } |
| 134 | public synchronized void toFirstDestination(){ |
| 135 | _position = _list.size() == 0 ? -1 : 0 ; |
| 136 | } |
| 137 | public synchronized void revert(){ |
| 138 | |
| 139 | Collections.reverse(_list); |
| 140 | toFirstDestination() ; |
| 141 | } |
| 142 | public synchronized boolean isFinalDestination(){ |
| 143 | return _position >= ( _list.size() - 1 ) ; |
| 144 | } |
| 145 | public synchronized boolean isFirstDestination(){ |
| 146 | return _position == 0 ; |
| 147 | } |
| 148 | CellAddressCore getCurrent(){ |
| 149 | if( ( _list.size() == 0 ) || |
| 150 | ( _position < 0 ) || |
| 151 | ( _position >=_list.size() ) )return null ; |
| 152 | return _list.get( _position ) ; |
| 153 | } |
| 154 | public CellAddressCore getDestinationAddress(){ |
| 155 | return _list.get(_list.size()-1); |
| 156 | } |
| 157 | void replaceCurrent( CellAddressCore core ){ |
| 158 | if( ( _list.size() == 0 ) || |
| 159 | ( _position < 0 ) || |
| 160 | ( _position >=_list.size() ) )return ; |
| 161 | _list.set(_position, core ) ; |
| 162 | } |
| 163 | public String getCellName(){ |
| 164 | CellAddressCore core = getCurrent() ; |
| 165 | return core == null ? null : core.getCellName() ; |
| 166 | } |
| 167 | public String getCellDomainName(){ |
| 168 | CellAddressCore core = getCurrent() ; |
| 169 | return core == null ? null : core.getCellDomainName() ; |
| 170 | } |
| 171 | /* |
| 172 | public void wasStored(){ |
| 173 | _storage = _list.size()-1 ; |
| 174 | } |
| 175 | public synchronized CellAddress getPreviousStorageAddress(){ |
| 176 | if( _storage < 0 )return null ; |
| 177 | CellAddress addr = new CellAddress(); |
| 178 | for( int i = _list.size() -1 ; i >= _storage ; i -- ) |
| 179 | addr.add( (CellAddressCore)_list.elementAt(i) ) ; |
| 180 | return addr ; |
| 181 | } |
| 182 | */ |
| 183 | public String toSmallString(){ |
| 184 | int size = _list.size() ; |
| 185 | if( size == 0 )return "[empty]" ; |
| 186 | if( ( _position >= size ) || ( _position < 0 ) )return "[INVALID]" ; |
| 187 | |
| 188 | CellAddressCore core = _list.get(_position) ; |
| 189 | |
| 190 | if( size == 1 ){ |
| 191 | return "["+core.toString()+"]" ; |
| 192 | } |
| 193 | |
| 194 | if( _position == 0 ) |
| 195 | return "["+core.toString()+":...("+(size-1)+")...]" ; |
| 196 | if( _position == (size-1) ) |
| 197 | return "[...("+(size-1)+")...:"+core.toString()+"]" ; |
| 198 | |
| 199 | return "[...("+_position+")...:"+ |
| 200 | core.toString()+ |
| 201 | "...("+(size-_position-1)+")...]" ; |
| 202 | |
| 203 | |
| 204 | } |
| 205 | public String toString(){ return toFullString() ; } |
| 206 | public String toFullString(){ |
| 207 | int size = _list.size() ; |
| 208 | if( size == 0 )return "[empty]" ; |
| 209 | if( ( _position >= size ) || ( _position < 0 ) )return "[INVALID]" ; |
| 210 | |
| 211 | StringBuilder sb = new StringBuilder() ; |
| 212 | |
| 213 | sb.append("[") ; |
| 214 | for( int i = 0 ; i < _list.size() ; i ++ ){ |
| 215 | if( i > 0 )sb.append(":") ; |
| 216 | if( i == _position )sb.append(">") ; |
| 217 | if( ( _storage > -1 ) && ( i == _storage ) )sb.append("*") ; |
| 218 | sb.append(_list.get(i).toString()); |
| 219 | } |
| 220 | sb.append("]") ; |
| 221 | return sb.toString(); |
| 222 | } |
| 223 | public synchronized boolean equals( Object obj ){ |
| 224 | if( ! ( obj instanceof CellPath ) )return false ; |
| 225 | |
| 226 | CellPath other = (CellPath)obj ; |
| 227 | synchronized( other ){ // not deadlock free |
| 228 | int s = 0 ; |
| 229 | if( ( s = _list.size() ) != other._list.size() )return false ; |
| 230 | |
| 231 | for( int i = 0 ; i < s ; i++ ) |
| 232 | if( |
| 233 | ! _list.get(i).equals(other._list.get(i)) |
| 234 | )return false; |
| 235 | |
| 236 | return true ; |
| 237 | } |
| 238 | } |
| 239 | public synchronized int hashCode(){ |
| 240 | int sum = 0 ; |
| 241 | for( CellAddressCore addr: _list ) { |
| 242 | sum += addr.hashCode() ; |
| 243 | } |
| 244 | return sum ; |
| 245 | } |
| 246 | |
| 247 | public static void main( String [] args ){ |
| 248 | CellPath addr = new CellPath() ; |
| 249 | for( int i = 0 ; i < args.length ; i ++ ){ |
| 250 | addr.add( args[i] ) ; |
| 251 | |
| 252 | } |
| 253 | System.out.println( addr.toFullString() ) ; |
| 254 | System.out.println( addr.toString() ) ; |
| 255 | while( addr.next() )System.out.println( addr.toString() ) ; |
| 256 | } |
| 257 | |
| 258 | |
| 259 | } |