| /* AbstractMap.java -- Abstract implementation of most of Map |
| Copyright (C) 1998, 1999, 2000 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. |
| |
| As a special exception, if you link this library with other files to |
| produce an executable, this library does not by itself cause the |
| resulting executable to be covered by the GNU General Public License. |
| This exception does not however invalidate any other reasons why the |
| executable file might be covered by the GNU General Public License. */ |
| |
| |
| // TO DO: |
| // comments |
| // test suite |
| |
| package java.util; |
| |
| public abstract class AbstractMap implements Map |
| { |
| /** |
| * Remove all entries from this Map. This default implementation calls |
| * entrySet().clear(). |
| * |
| * @throws UnsupportedOperationException |
| * @specnote The JCL book claims that this implementation always throws |
| * UnsupportedOperationException, while the online docs claim it |
| * calls entrySet().clear(). We take the later to be correct. |
| */ |
| public void clear() |
| { |
| entrySet().clear(); |
| } |
| |
| public boolean containsKey(Object key) |
| { |
| Object k; |
| Set es = entrySet(); |
| Iterator entries = es.iterator(); |
| int size = size(); |
| for (int pos = 0; pos < size; pos++) |
| { |
| k = ((Map.Entry) entries.next()).getKey(); |
| if (key == null ? k == null : key.equals(k)) |
| return true; |
| } |
| return false; |
| } |
| |
| public boolean containsValue(Object value) |
| { |
| Object v; |
| Set es = entrySet(); |
| Iterator entries = es.iterator(); |
| int size = size(); |
| for (int pos = 0; pos < size; pos++) |
| { |
| v = ((Map.Entry) entries.next()).getValue(); |
| if (value == null ? v == null : value.equals(v)) |
| return true; |
| } |
| return false; |
| } |
| |
| public abstract Set entrySet(); |
| |
| public boolean equals(Object o) |
| { |
| if (o == this) |
| return true; |
| if (!(o instanceof Map)) |
| return false; |
| |
| Map m = (Map) o; |
| Set s = m.entrySet(); |
| Iterator itr = entrySet().iterator(); |
| int size = size(); |
| |
| if (m.size() != size) |
| return false; |
| |
| for (int pos = 0; pos < size; pos++) |
| { |
| if (!s.contains(itr.next())) |
| return false; |
| } |
| return true; |
| } |
| |
| public Object get(Object key) |
| { |
| Set s = entrySet(); |
| Iterator entries = s.iterator(); |
| int size = size(); |
| |
| for (int pos = 0; pos < size; pos++) |
| { |
| Map.Entry entry = (Map.Entry) entries.next(); |
| Object k = entry.getKey(); |
| if (key == null ? k == null : key.equals(k)) |
| return entry.getValue(); |
| } |
| |
| return null; |
| } |
| |
| public int hashCode() |
| { |
| int hashcode = 0; |
| Iterator itr = entrySet().iterator(); |
| int size = size(); |
| for (int pos = 0; pos < size; pos++) |
| { |
| hashcode += itr.next().hashCode(); |
| } |
| return hashcode; |
| } |
| |
| public boolean isEmpty() |
| { |
| return size() == 0; |
| } |
| |
| public Set keySet() |
| { |
| if (this.keySet == null) |
| { |
| this.keySet = new AbstractSet() |
| { |
| public int size() |
| { |
| return AbstractMap.this.size(); |
| } |
| |
| public boolean contains(Object key) |
| { |
| return AbstractMap.this.containsKey(key); |
| } |
| |
| public Iterator iterator() |
| { |
| return new Iterator() |
| { |
| Iterator map_iterator = AbstractMap.this.entrySet().iterator(); |
| |
| public boolean hasNext() |
| { |
| return map_iterator.hasNext(); |
| } |
| |
| public Object next() |
| { |
| return ((Map.Entry) map_iterator.next()).getKey(); |
| } |
| |
| public void remove() |
| { |
| map_iterator.remove(); |
| } |
| }; |
| } |
| }; |
| } |
| |
| return this.keySet; |
| } |
| |
| public Object put(Object key, Object value) |
| { |
| throw new UnsupportedOperationException(); |
| } |
| |
| public void putAll(Map m) |
| { |
| Map.Entry entry; |
| Iterator entries = m.entrySet().iterator(); |
| int size = m.size(); |
| |
| for (int pos = 0; pos < size; pos++) |
| { |
| entry = (Map.Entry) entries.next(); |
| put(entry.getKey(), entry.getValue()); |
| } |
| } |
| |
| public Object remove(Object key) |
| { |
| Iterator entries = entrySet().iterator(); |
| int size = size(); |
| |
| for (int pos = 0; pos < size; pos++) |
| { |
| Map.Entry entry = (Map.Entry) entries.next(); |
| Object k = entry.getKey(); |
| if (key == null ? k == null : key.equals(k)) |
| { |
| Object value = entry.getValue(); |
| entries.remove(); |
| return value; |
| } |
| } |
| |
| return null; |
| } |
| |
| public int size() |
| { |
| return entrySet().size(); |
| } |
| |
| public String toString() |
| { |
| Iterator entries = entrySet().iterator(); |
| int size = size(); |
| StringBuffer r = new StringBuffer("{"); |
| for (int pos = 0; pos < size; pos++) |
| { |
| // Append the toString value of the entries rather than calling |
| // getKey/getValue. This is more efficient and it matches the JDK |
| // behaviour. |
| r.append(entries.next()); |
| if (pos < size - 1) |
| r.append(", "); |
| } |
| r.append("}"); |
| return r.toString(); |
| } |
| |
| public Collection values() |
| { |
| if (this.valueCollection == null) |
| { |
| this.valueCollection = new AbstractCollection() |
| { |
| public int size() |
| { |
| return AbstractMap.this.size(); |
| } |
| |
| public Iterator iterator() |
| { |
| return new Iterator() |
| { |
| Iterator map_iterator = AbstractMap.this.entrySet().iterator(); |
| |
| public boolean hasNext() |
| { |
| return map_iterator.hasNext(); |
| } |
| |
| public Object next() |
| { |
| return ((Map.Entry) map_iterator.next()).getValue(); |
| } |
| |
| public void remove() |
| { |
| map_iterator.remove(); |
| } |
| }; |
| } |
| }; |
| } |
| |
| return this.valueCollection; |
| } |
| |
| private Collection valueCollection = null; |
| private Set keySet = null; |
| } |