Update of /cvsroot/hibernate/Hibernate2/src/net/sf/hibernate/util
In directory sc8-pr-cvs1:/tmp/cvs-serv7760/hibernate/util
Modified Files:
IdentityMap.java
Log Message:
enable use of JDK IdentityHashMap in 1.4+
Index: IdentityMap.java
===================================================================
RCS file: /cvsroot/hibernate/Hibernate2/src/net/sf/hibernate/util/IdentityMap.java,v
retrieving revision 1.3
retrieving revision 1.4
diff -C2 -d -r1.3 -r1.4
*** IdentityMap.java 5 Jan 2003 02:11:25 -0000 1.3
--- IdentityMap.java 16 Feb 2003 01:55:07 -0000 1.4
***************
*** 2,16 ****
package net.sf.hibernate.util;
- import java.util.HashMap;
import java.io.Serializable;
! import java.util.*;
/**
! * A hashtable where keys are compared by object identity,
! * rather than equals().
*/
public final class IdentityMap implements Map, Serializable {
private final Map map = new HashMap();
--- 2,69 ----
package net.sf.hibernate.util;
import java.io.Serializable;
! import java.util.ArrayList;
! import java.util.Collection;
! import java.util.HashMap;
! import java.util.HashSet;
! import java.util.Iterator;
! import java.util.List;
! import java.util.Map;
! import java.util.Set;
!
! import net.sf.hibernate.AssertionFailure;
/**
! * A <tt>Map</tt> where keys are compared by object identity,
! * rather than <tt>equals()</tt>.
*/
public final class IdentityMap implements Map, Serializable {
+ private static final Class identityMapClass;
+ static {
+ Class imc;
+ try {
+ imc = Class.forName("java.util.IdentityHashMap");
+ //throw new ClassNotFoundException();
+ }
+ catch (ClassNotFoundException cnfe) {
+ imc = IdentityMap.class;
+ }
+ identityMapClass=imc;
+ }
+
+ /**
+ * Return a new instance of this class, or an instance of JDK <tt>IdentityHashMap</tt>,
+ * if available. (The JDK implementation is significantly faster.)
+ *
+ * @return Map
+ */
+ public static Map instantiate() {
+ try {
+ return (Map) identityMapClass.newInstance();
+ }
+ catch (Exception ie) {
+ throw new AssertionFailure("could not instantiate identity map", ie);
+ }
+ }
+
+ /**
+ * Return the map entries (as instances of <tt>Map.Entry</tt> in a collection that
+ * is safe from concurrent modification). ie. we may safely add new instances to
+ * the underlying <tt>Map</tt> during iteration of the <tt>entries()</tt>.
+ *
+ * @param map
+ * @return Collection
+ */
+ public static Collection entries(Map map) {
+ if (identityMapClass==IdentityMap.class) {
+ return ( (IdentityMap) map ).entryList();
+ }
+ else {
+ return new ArrayList( map.entrySet() );
+ }
+ }
+
private final Map map = new HashMap();
***************
*** 50,73 ****
}
}
!
! private static IdentityKey popKey(Object key) {
!
! /*synchronized(keyCache) {
! if ( keyCache.isEmpty() ) {
! return new Key(key);
! }
! else {
! Key k = (Key) keyCache.pop();
! k.key = key;
! return k;
! }
! }*/
! return new IdentityKey(key);
! }
!
! private static void pushKey(IdentityKey k) {
! //keyCache.push(k);
! }
!
public int size() {
return map.size();
--- 103,107 ----
}
}
!
public int size() {
return map.size();
***************
*** 79,86 ****
public boolean containsKey(Object key) {
! IdentityKey k = popKey(key);
! boolean result = map.containsKey(k);
! pushKey(k);
! return result;
}
--- 113,118 ----
public boolean containsKey(Object key) {
! IdentityKey k = new IdentityKey(key);
! return map.containsKey(k);
}
***************
*** 90,108 ****
public Object get(Object key) {
! IdentityKey k = popKey(key);
! Object result = map.get(k);
! pushKey(k);
! return result;
}
public Object put(Object key, Object value) {
! return map.put( popKey(key), value );
}
public Object remove(Object key) {
! IdentityKey k = popKey(key);
! Object result = map.remove(k);
! pushKey(k);
! return result;
}
--- 122,136 ----
public Object get(Object key) {
! IdentityKey k = new IdentityKey(key);
! return map.get(k);
}
public Object put(Object key, Object value) {
! return map.put( new IdentityKey(key), value );
}
public Object remove(Object key) {
! IdentityKey k = new IdentityKey(key);
! return map.remove(k);
}
***************
*** 116,123 ****
public void clear() {
- Iterator iter = map.keySet().iterator();
- while ( iter.hasNext() ) {
- pushKey ( (IdentityKey) iter.next() );
- }
map.clear();
}
--- 144,147 ----
***************
*** 133,137 ****
public Set entrySet() {
! Set set = new HashSet();
Iterator iter = map.entrySet().iterator();
while ( iter.hasNext() ) {
--- 157,161 ----
public Set entrySet() {
! Set set = new HashSet( map.size() );
Iterator iter = map.entrySet().iterator();
while ( iter.hasNext() ) {
***************
*** 140,143 ****
--- 164,222 ----
}
return set;
+ }
+
+ private List entryList() {
+ ArrayList list = new ArrayList( map.size() );
+ Iterator iter = map.entrySet().iterator();
+ while ( iter.hasNext() ) {
+ Map.Entry me = (Map.Entry) iter.next();
+ list.add( new IdentityMapEntry( ( (IdentityKey) me.getKey() ).key, me.getValue() ) );
+ }
+ return list;
+ }
+
+ /**
+ * Workaround for a JDK 1.4.1 bug where <tt>IdentityHashMap</tt>s are not
+ * correctly deserialized.
+ *
+ * @param map
+ * @return Object
+ */
+ public static Object serialize(Map map) {
+ if (identityMapClass==IdentityMap.class) {
+ return map;
+ }
+ else {
+ Object[] array = new Object[ map.size() * 2 ];
+ Iterator iter = map.entrySet().iterator();
+ int i=0;
+ while ( iter.hasNext() ) {
+ Map.Entry e = (Map.Entry) iter.next();
+ array[i++] = e.getKey();
+ array[i++] = e.getValue();
+ }
+ return array;
+ }
+ }
+
+ /**
+ * Workaround for a JDK 1.4.1 bug where <tt>IdentityHashMap</tt>s are not
+ * correctly deserialized.
+ *
+ * @param map
+ * @return Object
+ */
+ public static Map deserialize(Object o) {
+ if (identityMapClass==IdentityMap.class) {
+ return (Map) o;
+ }
+ else {
+ Map map = instantiate();
+ Object[] array = (Object[]) o;
+ for ( int i=0; i<array.length; i+=2 ) {
+ map.put( array[i], array[i+1] );
+ }
+ return map;
+ }
}
}
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